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siliconchip.com.au March 2006  1 SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: www.jaycar.com.au Contents www.siliconchip.com.au Vol.19, No.3; March 2006 FEATURES    8 The Electronic Camera, Pt.1 They’re more expensive than film cameras and require skill to produce quality prints. So why are they leaping off retailers’ shelves? – by Kevin Poulter 16 The World’s Most Highly Modified Hybrid Car Only a fruit-loop would modify a car with no less than six electronic control units, a 288V battery and two electric motor/generators – by Julian Edgar The Electronic Camera – Page 8. 44 Six Low-Cost Expansion Boards For The AVR200 Add up to 128 bits of digital I/O, a keypad and LCD, more non-volatile memory – or a combination of any of these – by Peter Smith 80 Salvage Engineering Intercooler Water Spray Controller – Page 38. Spend a few dollars on a solar-powered garden light and what do you get? Parts that are worth salvaging for other projects, that’s what! – by Stan Swan PROJECTS TO BUILD 30 PC-Controlled Burglar Alarm System, Pt.2 Testing and driving the new alarm system. We also show you how to build the optional keypad module – by Trent Jackson 38 Low-Cost Intercooler Water Spray Controller A cheap but sophisticated way of controlling a turbo car’s intercooler water spray. It’s also really easy to build – by Julian Edgar 64 AVR ISP SocketBoard Team it with an AVR in-system programmer (ISP) and you can program just about all DIL Atmel microcontrollers on the spot – by Peter Smith 70 A Line Tracker For Your Microbric Viper Keep it on the straight and narrow or follow the curves – by Ross Tester 84 Phone/Fax Missed Call Alert It detects an incoming call and lights a LED or sounds a horn in another room or your garage – by Jim Rowe SPECIAL COLUMNS AVR ISP SocketBoard – Page 64. 48 Serviceman’s Log The beautiful-looking Philips TV set – by the TV Serviceman 72 Circuit Notebook (1) Steam & Diesel Loco Sounds; (2) Long Life Lamp Beacon; (3) Accurate Milliohm Meter; (4) Sensitive Over-Current Protector; Delay Circuit For Power Windows; (5) Versatile Electronic Load 90 Salvage It! A low-cost large display anemometer – by Julian Edgar 98 Vintage Radio The unique Healing “Scales” 403E receiver – by Rodney Champness DEPARTMENTS   2   4 61 103 Publisher’s Letter Mailbag Product Showcase Order Form siliconchip.com.au 104 107 110 112 Ask Silicon Chip Notes & Errata Market Centre Ad Index Large Display Anemometer From Salvage Parts – Page 90. March 2006  1 SILICON CHIP www.siliconchip.com.au Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Production Manager Greg Swain, B.Sc.(Hons.) Technical Editor Peter Smith Technical Staff John Clarke, B.E.(Elec.) Ross Tester Jim Rowe, B.A., B.Sc, VK2ZLO Reader Services Ann Jenkinson Advertising Enquiries Lawrence Smith Benedictus Smith Pty Ltd Phone (02) 9211 8035 Fax: (02) 9211 0068 lawrence<at>benedictus-smith.com Regular Contributors Brendan Akhurst Rodney Champness, VK3UG Julian Edgar, Dip.T.(Sec.), B.Ed, Grad.Dip.Jnl Mike Sheriff, B.Sc, VK2YFK Stan Swan SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. ACN 003 205 490. ABN 49 003 205 490 All material copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing: Hannanprint, Noble Park, Victoria. Distribution: Network Distribution Company. Subscription rates: $83.00 per year in Australia. For overseas rates, see the subscription page in this issue. Editorial office: Unit 8, 101 Darley St, Mona Vale, NSW 2103. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9979 5644. Fax (02) 9979 6503. E-mail: silchip<at>siliconchip.com.au Publisher’s Letter Standard definition plasma TV sets are not the best proposition This month, one of our correspondents to Mailbag (page 7) draws attention to the fact that some plasma TV sets being sold on the Australian market have 852 x 480 pixels. This is fine for the American market because NTSC broadcasts have 480 visible scanning lines (out of a total of 525 lines). But it is inadequate for PAL broadcasts which have 576 visible scanning lines (out of a total of 625 scanning lines). The set has to scale the incoming video signal to suit the number of vertical pixels so inevitably, you lose vertical picture resolution. Putting it another way, the picture on such standard definition plasma sets can never be as detailed as on a good CRT set. But the situation is actually worse. Rather than just some plasma sets being only 852 x 480 pixels, it appears that ALL standard definition wide-screen plasma sets conform to this standard. Why? Because they are all designed to suit the American market. Sure, some of them might be HD-ready, able to accept a signal from a HD set-top box via a digital HDMI cable or analog component video (with progressive scan) but they can never display HD signals with anything more than 852 x 480 resolution. Plasma sets (HD or SD) also use a lot of power, typically between 300 and 500 watts, depending on screen size. Just check out any plasma set in your local retailer – you can feel the heat radiating from the screen and from the top of the cabinet. That may not be a problem in winter, when it just contributes to your room heating but it is a lot of heat in summer. If you are running an air-conditioner, it will have to work that much harder to get rid of the excess heat. I also feel that any set producing that much heat must present a long-term reliability prospect. All the electronic componentry behind the screen is subject to much of that heat. Temporary image burn-in of station logos also seems to be a problem, even on the current generation of plasma TVs. While this may not do any permanent harm, it can be extremely irritating to see a channel logo still there, maybe days afterwards you watched several hours of a sports broadcast. One cannot deny that plasma TVs are initially very attractive when you see them on display in the stores. They are very bright and colourful and when shown with any cartoon features, they seem even brighter. Our advice? Look carefully before you leap. Consider a high-definition LCD set or even a rear projection set over any SD plasma set. If those models seem too expensive, just wait a year – they will be much cheaper then. And don’t be conned by extreme claims for contrast ratio. A press release for a new SD plasma set that arrived while I was writing this very editorial claims a contrast ratio of 10,000:1. This is ridiculous. Leo Simpson ISSN 1030-2662 * Recommended and maximum price only. 2  Silicon Chip siliconchip.com.au Innovative • Unique • Interesting • Hard to find products Cordless Barcode Scanner This cordless CCD scanner uses Bluetooth technology for reliable & accurate performance. Comes with Bluetooth dongle. Requires AA batteries (not included) Cat 1008178-7 $699 What’s New? VGA Splitter/Booster Dual ADSL Router A powered VGA splitter that can run the second monitor up to 80m from the PC. Cat 3445-7 $199 Enhance reliability and double your ADSL capacity by using two different ISP's. Cat 10145-7 $214 Pentium 4 with ISA Now supports LGA 775 CPUs! This industrial motherboard is based on the Intel i915G chipset. It supports LGA 775 Prescott processors and has 1 PCI Express x16, 1 PCI Express x1, 3 PCI, and 2 ISA slots. Cat 17096-7 $699 USB to IDE Adapter with Power Easily connect any IDE drives to your PC using a high-speed USB 2.0 port. An external power adapter is included to power drives if necessary. It supports desktop IDE drives and Notebook IDE drives with its 40 & 44 pin connectors. Cat 6857-7 $48 12v Mini PC PCMCIA Dual Slot for PC This Dual Slot PCMCIA adapter for PC allows a PCMCIA device to be used in a PC. The two built-in PCMCIA sockets in the 3.5" front Drive Unit connect to the PCI Interface Card. Cat 6482-7 $199 Wireless VGA Receiver Using an existing wireless network and the software provided, the user can duplicate and transmit their display to a projector or plasma screen etc. Perfect for schools, boardrooms, lecture theatres etc. Cat 3582-7 $679 Mini Keyboard with Touchpad Compact 88 key keyboard with an integrated touch pad pointing device. It has two PS/2 connections for mouse and keyboard. Cordless model available. Cat 8751-7 $139 Extend USB 50m Cash Drawer Use inexpensive network cable (not included) to A robust cash drawer that is compatible with extend any USB 1.1 device up to 50m from a all major receipt printers and POS software. PC. Cat 11666-7 $99 Cat 8897-7 $179 Digital I/O to Ethernet This unit allows the user to remotely control 7 Digital I/O ports and 1 RS232/422/485 port over LAN or WAN. Cat 15157-7 $329 VGA Extender Extend VGA up to 130m over inexpensive STP cable. Cat 3441-7 $399 Mini Personal Data Collector (MPDC) Stores up to 1000 barcodes The MPDC offers a portable scanning solution that includes the functionality of larger, bulkier units and features a 64 character LCD, Serial Interface and rechargeable batteries. Cat 9286-7 $399 Windows Based Terminal LCD Monitor Arm Holds up to a 17" LCD. Uses standard VESA mounts and can be attached to a wall or desk. Cat 4666-7 $99 This tiny WBT can attach to the VESA mounts on a LCD monitor. It supports RDP and emulates SCO, DEC, Wyse etc. Cat 1239-7 $649 • Normally delivered next day • 8 Port Serial Card Add 8 serial ports to a standard PC with this PCI card. It comes with DB25 connectors via octopus cable. Cat 2677-7 $670 Not sure what product you require? Call us for friendly advice! ask<at>mgram.com.au 1800 625 777 Digital I/O Card A PCI card that provides 48 digital I/O lines and three 16bit counters with a maximum count rate of 10MHz. Cat 17053-7 $249 www.mgram.com.au Great for servers this RAID device takes two IDE drives IP KVM and mirrors them. If one drive fails Attach this unit to any it will work from existing KVM and access all your machines the other until the faulty one is replaced remotely with a web and then rebuild "on the fly" to minimize browser to a BIOS level. downtime. Cat 11674-7 $899 Cat 2874-7 $569 PCMCIA to Serial Add two serial ports to your notebook. Cat 2726-7 $269 USB Temp and Humidity Sensor RAID Server Sharp Cash Register A basic cash register that is suitable for small retail outlets. Cat 1008129-7 $289 EPROM Programmer This programmer connects to the LPT port and has a 32 pin ZIF socket. It will program from 16k to 8M. Cat 3159-7 $479 Measures the relative humidity and temperature and can graph the results on the included software. Cat 17090-7 $319 Reseller inquiries welcome siliconchip.com.au USB VGA Adapter Plugs into a USB 2.0 port and allows the user to extend their desktop over two screens (or three screens if already using a dual head video card). Cat 15156-7 $149 Console Sharer Allows two workstations to operate the one PC. Supports PS/2 keyboard and mouse with VGA monitor. Cat 11667-7 $139 1800 625 777 ask<at>mgram.com.au www.mgram.com.au March 2006  3 All prices subject to change without notice. For current pricing visit our website. Pictures are indicative only. SHORE AD/MGRM0306 This mini barebones PC is based on the VIA Eden 800Mhz processor and motherboard. It can operate on 12v or 240v making it ideal for use in boats or cars. Cat 1167-7 $750 MAILBAG Compact fluoros do comply with Australian standards Graham Lill seems very concerned about the 1mm track spacing on the mains side of the PC board of his disassembled compact fluoro (SILICON CHIP, Jan. 2006, page 7). Having spent six months in a Melbourne Lab testing, for a large part of the time, compact fluoros with very similar PC boards, I can assure Graham that all is well (assuming that the product was bought from a reputable supplier). The product would have been tested to Australian (Safety) Standards before being allowed for sale. If my memory is correct, AS3100 sets down the testing methods and one of the tests is the clearance between live parts, in this case Active & Neutral. There are other specific safety standards for rigorous testing of this product. The Active & Neutral would be my least concern as these have a potential difference (PD) of only 230VAC RMS (as per AS3000) whereas the four leads to the tube could have a PD of up to 2500V RMS (VDC + VAC). If I recall correctly, 2.5kV is the limit set by the Standard and I have measured well in excess of this on products provided for testing. These products failed and were returned to the manufacturer for suitable modifications. For peace of mind, purchase only products tested to Australian Standards – the C tick (EMC Compliance) is a good indication that the product complies. Mike Abrams, MIEAust, Capalaba, Qld. Unmute facility for portable PA amplifier In the January 2006 issue, pages 115 & 116, you published a possible solution for an unmute facility for the PortaPal PA system. I had a similar requirement and tackled the problem slightly differently. I mounted a SPDT (centre off) switch on the front panel and connected +12V and Gnd to either end of the switch. For simplicity, I made connections to either side of D3 from the component side of the board. I then connected the common of the 4  Silicon Chip switch to the anode of D2, again from the component side. This now gives me the flexibility to use the device as per the original design (centre off position), permanently suppress the mute so that initial chords of the guitar riff are not lost or alternatively, force the permanent mute. The latter allows signals to be pulled off from the line out and fed to other systems, etc without coming through the speaker. It only takes about half an hour to modify and I have been using it like this for about six months with no problems. Mick McCarthy, via email. Support for nuclear power I was very interested in your editorial (SILICON CHIP, January 2006) to see you suggesting nuclear power for Australia. Except for Sir William McMahon, we would have had a power station at Jervis Bay and probably several more by now. It’s ideally suited to this country. It’s clean, we have plenty of fuel and being a stable country geologically we can store the small amounts of waste quite easily. I am sure that if the general public understood more about it we would not get the reactions we usually get, as these are based on lack of knowledge and fear of the unknown. Some years back, the Australian Atomic Energy Commission carried out a study into the “most credible accident” to try to estimate how many deaths and injuries would follow a genuine major failure in an atomic power station. Mean time between failures was taken into account and the study also included conventional power stations as a comparison. The study covered all deaths from the time of producing the fuel to disposing of the waste products. It soon became apparent that the number of deaths from a nuclear accident was likely to be far less than the number of people killed during the normal production of power by conventional means. If we look back over forty years or so, the number of deaths in the western world from nuclear power or any accidents involving the production of nuclear power is far less than the deaths associated with more conventional power generation. In time, solar power and other forms of non-polluting power will undoubtedly take over but these technologies have somewhat further to go in their development to become really viable. In the meantime, we could and should use nuclear energy to reduce our greenhouse gas emissions, as our energy needs are only going to grow in years to come. I probably should declare my interest here – my father was chairman of the AAEC from 1957 to 1972 and led one of the British teams to the US during the war to help the Americans build the two atomic bombs that were dropped on Japan. So I grew up in an atmosphere that was positive about nuclear energy and the benefits it has for us all. I am still positive about the benefits of nuclear power. Rod Baxter, via email. We should develop fast neutron reactors I wholeheartedly agree with your editorial suggesting that Australia should build nuclear power stations. It is clear that renewable energy in the form of solar or wind is not going to be close to providing enough power to meet our needs and in order to actually shut down existing coal/oil/gas power stations, nuclear power is the only viable solution. Further, the December issue of “Scientific American”, Smarter Use of Nuclear Waste (http://tinyurl. com/7bp8w), talks about fast neutron reactors. These can extract power from 99% of uranium or plutonium siliconchip.com.au Atmel’s AVR, from JED in Australia JED has designed a range of single board computers and modules as a way of using the AVR without SMT board design Seismograph plots of a recent earthquake I have attached two recordings of a Magnitude 7.7 earthquake from the Banda Sea in Indonesia. The quake occurred on Saturday morning (January 27th, UTC). One recording was made with the “Picaxe” seismograph detector sending data to the “StampPlot” graphing program, exactly as in the SILICON CHIP article in September 2005. The second recording was using a magnetic coil/magnet detector feeding a Dataq DI194 RS data analog to digital converter (an option suggested in the article) and displayed using a program called AmaSeis. The seismographs were identical to the article design. AmaSeis presents the detected data so that it looks like the traditional seismograph helical recorders. Each line is one hour and the bottom line is the current hour. The advantage of this is that you can see the last 20+ hours on the one screen. Dave Dobeson, via email. The AVR570 module (above) is a way of using an ATmega128 CPU on a user base board without having to lay out the intricate, surface-mounted surrounds of the CPU, and then having to manufacture your board on an SMT robot line. Instead you simply layout a square for four 0.1” spaced socket strips and plug in our pre-tested module. The module has the crystal, resetter, AVR-ISP programming header (and an optional JTAG ICE pad), as well as programming signal switching. For a little extra, we load a DS1305 RTC, crystal and Li battery underneath, which uses SPI and port G. See JED’s www site for a datasheet. AVR573 Single Board Computer (including non-radioactive uranium and uranium/plutonium waste from existing nuclear reactors and superfluous weapons-grade plutonium), while producing waste that is radioactive for only 300 years (instead of 10,000) and never requiring or producing pure weapons-grade materials. If Australia was to start importing and storing nuclear waste now, while designing and developing fast-neutron reactors, not only could we earn money from exporters of nuclear waste, we could turn that 10,000-year storage waste into 300-year storage waste while providing power with negligible impact on the environment. For anyone who is opposed to nuclear power on the grounds of potential disasters, they would do well to remember that all existing power stations pollute the air, leading directly to deaths in nearby populations as well as contributing to global warming. Australia is in a unique position to both accept nuclear waste and develop fast-neutron reactors. Peter N. Lewis, via email. siliconchip.com.au Distributed power generation is the answer I feel compelled to respond to your assertion that we should build nuclear power plants to replace the coal and gas plants dotted about the country. I don’t really have any concerns regarding safety or waste issues, though it is difficult to sort through the misinformation that abounds. No, the problem I have is that nuclear is simply a variation of old technology that is a bit past its “use by” date. Firstly, central generation is incredibly wasteful; coal-fired power stations generally run at some 35% efficiency. Thus for every 100 units of fuel energy going in, only 35 units of electrical energy come out; 65% is wasted as heat in those huge cooling towers. The waste is inherent any heat engine; nuclear is no exception. Secondly, the power grid is already groaning under the load and the demand doesn’t look to be decreasing any time soon. My solution is distributed generation. Technology has progressed to the point where it is possible to efficiently This board uses the AVR570 module and adds 20 An./Dig. inputs, 12 FET outputs, LCD/ Kbd, 2xRS232, 1xRS485, 1-Wire, power reg. etc. See www.jedmicro.com.au/avr.htm $330 PC-PROM Programmer This programmer plugs into a PC printer port and reads, writes and edits any 28 or 32-pin PROM. Comes with plug-pack, cable and software. Also available is a multi-PROM UV eraser with timer, and a 32/32 PLCC converter. JED Microprocessors Pty Ltd 173 Boronia Rd, Boronia, Victoria, 3155 Ph. 03 9762 3588, Fax 03 9762 5499 www.jedmicro.com.au March 2006  5 Mailbag: continued Lithium polymer batteries must be treated with care It was nice to see the electric flight article in the February 2006 issue. Unfortunately, your information and advice on LiPO (lithium polymer) batteries is incorrect and could result in your readers destroying their cells. First of all, in the figure on page 11 you show an 1800mAh 3S (three series cell) pack but you have nominated the voltage as 11.4V. This is incorrect as this is an 11.1V (12.6V fully charged) pack. LiPO cells have a nominal cell voltage of 3.7V, with a fully charged voltage of 4.2V. Then on page 15, in the second last paragraph, you state that modern electronic speed controllers have a built-in LiPO low voltage cutout of 2.4V per cell. If this was the case, the cells would already have been permanently damaged, as the widely accepted level is 3.0V per cell. This is from manufacturers’ and distributors’ information. On page 19, you repeat this incorrect information on your warning page. You also state that you should never exceed a discharge current of 9C, which may be correct for one particular manufacturer’s battery but is by no means correct for many modern LiPOs which are capable of 12C or more (according to their technical data). Contrary to the (now old) views that these cells are about as safe as a bottle of nitroglycerine, modern cells in general are quite safe given a reasonable level of respect. Yes, there are certain safety rules which will make usage even safer but the same can be said of high energy Nicad or NiMH cells. Charging these cells using very simple home-made chargers is quite feasible and is very popular within the RC community. For an excellent source of information on these and many other electric flight resources I would recommend the www.rcgroups.com free forums. Ingmar Meins, Griffith, NSW. 6  Silicon Chip Bob Young comments: I am afraid Ingmar is suffering a severe case of message sent does not equal message received. (1) On page 15 I said that the ESC has a low voltage cutout to prevent the batteries falling below 2.4V per cell (the destruction point of LiPOs). I did not say the ESC was set to cut off at 2.4V – it just means that the cut-off prevented the batteries from ever reaching the point at which the batteries will destroy themselves. (Some sources quote 2.5V per cell as the destruction point, by the way). (2) On page 19 I again quoted the accepted destruction voltage, not the safety cut-off point. At no point in that article did I ever quote a safety cut-off point. I am only ever talking of the point at which the batteries will be ruined and pointing out that the batteries must never reach that point. A safety cut-off is not going to stop self-discharge destroying a battery. (3) The figure of 11.4V is incorrect and for this I apologise – a bit of dyslexic transposition between 7.4V and 11.1V, the figures quoted on my LiPO charger I am afraid. (4) 9C was the commonly quoted figure in the reading that I did on these cells. Some modern cells I have found out since are quoted as low as 7C. Nobody is going to get into trouble using a battery at 9C even if it is a 12C battery. I prefer to be conservative. There have been some very nasty accidents recently in Australia with these batteries and they must be treated with great care. I stand by that. generate your own power in your back yard and sell any excess back to the power company. The grid then needs to deliver less power overall and the “waste” heat generated is easily harnessed to heat water and living areas, and even power air-conditioning and refrigeration rather than dissipating into the atmosphere. Even better is that one would have the option of powering the “backyard utility” with sustainable fuels such as ethanol, edible oils, bio-diesel, wood, etc and produce zero net CO2. It is not a good solution for everyone or everywhere and like any form of alternative energy, it needs careful analysis to match the application with the hardware. Nenad Stojadinovic, via email. Power can come from hot rocks So you advocate nuclear power generation. There is a far cheaper and extremely environmentally friendly solution right under your feet – “hot rocks”. The only major and different expense for this technology is for the $1,000,000 per kilometre (using current proven techniques) to drill the down to the required depth. Now this depth may seem excessive at up to 12km but it can be done. And with the newer techniques of microwave cracking of the rocks and even laser cutting (ex-Boeing), it will be even cheaper in the near future. Of course, insulated pipes are then needed to bring that very hot water back to the surface but again the technology is easily available. When you have that water at the surface it is expanded into steam to drive a standard steam turbine to generate electricity. No towers are needed as the output hot water is simply sent back underground. South Australia is already investing money into this technology, at Coopers Creek. Bruce Withey, Grafton, NSW. BPL trials held in isolation I have been reading the Mailbag feedback on BPL (SILICON CHIP, January & February 2006) with interest. siliconchip.com.au 2006 SILICON CHIP Excellence in Education Technology Awards SILICON CHIP magazine aims to promote the education, development and application of electronic technology in all fields throughout Australia. As part of that aim, we are announcing the SILICON CHIP Excellence in Education Technology awards, with a prize pool of $10,000. Separate awards will be made to students of secondary schools throughout Australia and to students of universities and TAFE colleges throughout Australia. The secondary school awards will have three categories: AWARD FOR EXCELLENCE (a) Best final year assignment of an individual student involving electronics technology (b) An award to the school sponsoring the winning individual student (c) Best school project involving electronics technology The university and TAFE college awards will have three categories: (a) Best project from a student as part completion of a degree, diploma or certificate in electronics or a related field (ie, mechatronics) (b) Best research project from a post-graduate student working in an area of applied electronics (c) An award to the university faculty or school sponsoring the best research project. Entries and judging The awards will be judged by the editorial staff of SILICON CHIP, convened as a judges panel. The decisions of the judges will be final. Entries for the 2006 awards will open 1st May 2006, with final submissions to be made by September 30th, 2006. All submissions will be confidential, until the winners are announced, in the December 2006 issue of SILICON CHIP. Each award will take the form of a cash prize and a commemorative plaque. All enquiries about these awards should be directed to the editor via email to: awards<at>siliconchip.com.au While I’m not qualified to comment in a technical way, I do have many years of experience to draw on. There’s one factor that’s been overlooked so far in the trials of BPL currently underway in a Hobart suburb. That factor is isolation. The suburb where the trials are currently underway is called Tolmans Hill, a new suburb of just a few dozen houses at most. Being surrounded by trees, Tolmans Hill is at least 1km from the nearest buildings in all directions. It has a very large hill in between to screen other Hobart areas from it. If I had to pick the perfect place to trial BPL and I wanted to claim no interference to others, Tolmans Hill would be it. So any data regarding interference from BPL in these trials should be viewed with caution because there are not many people living close enough to have any real problems with it. Before any decision is made regarding the introduction of BPL, trials should be undertaken in other Aussiliconchip.com.au tralian inner city areas. I think this way we will quickly find out if there’s a problem from interference, or not. Jack Gill, via email. Some Plasma TVs only have 480 vertical pixels I agree with your sentiments that (some) “home theatre systems are not worth watching” (Publisher’s Letter, SILICON CHIP, February 2006) but for a different reason. Some systems being sold into the Australian market are actually designed for the lower resolution NTSC system used primarily in North America and Japan. PAL (the Australian TV standard) has 576 visible scanning lines (vertically) whereas NTSC has only 480 visible lines. Displays designed for the NTSC market therefore usually only have a vertical resolution of 480 pixels. Displaying a PAL signal on a lower resolution panel (one designed for the NTSC market) results in a loss of approximately 17% of resolution in the vertical direction. Last year a nearby store had a plasma TV on display which had this exact problem. The native resolution of the panel was 852 x 480, which is incapable of fully displaying PAL’s 576 lines (any PAL signal would be interpolated down to 480 lines). And yet there was an advertising sign on the unit which said “higher resolution than standard television”. This is blatantly untrue. It is true that the horizontal resolution of this set was higher than the 720 pixels provided by digital SD PAL broadcasts, however you can’t invent resolution and certainly does not make up for the loss of resolution in the vertical direction. Imagine my horror when I realised that the Epson projector reviewed in the February issue exhibits this same problem. The native resolution of this projector is only 854 x 480; fine in the horizontal direction but terrible in the vertical direction. Andrew Woods, Curtin University of Technology, Perth, WA. March 2006  7 Digital cameras are significantly more expensive than film cameras and require considerable time and skill to produce quality prints. So why are they leaping off delighted retailers’ shelves? Part 1: By Kevin Poulter The Electro T here are three main reasons for the sales success of digital cameras: one of the most intensive marketing campaigns in history, peer pressure to be up to date and yes, digital has some advantages over film. The major advantages? (1) No film or processing costs; (2) Ability to preview the results immediately for a quality check; (3) Automatic white balance; (4) Immediate results – view and transmit images via the Internet or as prints, in minutes; (5) No waiting to complete a roll of film; and (6) Easy to carry, compact size. The rationale of these articles is to cover technical information generally not in camera magazines, without replacing the 200-page manual supplied with prosumer cameras. Without film and processing costs, digital photography is effectively free, so it’s a breeze to take more images. This invariably leads to more choices, enabling amateurs to produce better images, plus professionals save time and know how their images will look. There are industrial and business advantages too, like incredibly detailed, lower power x-rays – safer, more informative and quicker than conventional technology. Results are easily viewed, stored and transmitted, with computer 8  Silicon Chip Digital x-rays (right) need less power than conventional (left) and exhibit much more detail. In this case, the dark area seen in the digital x-ray is very important. The very light area of filling is not a problem, as the software has brightness and contrast controls. siliconchip.com.au onic Camera controls like brightness, cropping and sharpness. Automatic white balance is a brilliant exclusive-to-digital feature. Of all the advantages, the immediacy leads as the standout attraction. Some of the digital advantages can also have their own disadvantages: (1) No film/processing cost for images means the photographer usually takes many more shots of the same thing. (2) Previewing the results immediately for a quality check takes time. (3) Considerable computer time and “grunt”, plus quite detailed knowledge of image processing software, is needed to achieve the best images. Aren’t the first two points the same as the advantages? Yes, but with a sting! Professional and amateur photographers can produce thousands of images, so vast hard drive space is needed, requiring more investment in computer hardware and possibly software. This leads to very expensive repercussions, which will be highlighted in the second part of this series. Digital cameras are more aptly titled ‘electronic cameras’, siliconchip.com.au as nearly every component and innovation is electronic. From the first image capture to outputting as prints, digital photography relies on a flow of electrons. Even the zoom and ‘manual’ focus in lenses is often achieved via motors within the lens. Compared to film counterparts, digital cameras have undergone exponential development since their introduction just a decade ago. Digital photography’s evolution relied on new complementary technologies, requiring rapid upgrading of emerging technology – such as the personal computer, memory cards, batteries, image sensors and infrastructure, even enlarging booths. Improvements in image resolution compared to digital camera prices have been nothing short of astounding. This is fuelled by demand, competition and the rise and rise of China as a source of cheap production. Quality digital cameras are now as low as a third of the price of comparable units just 12-18 months ago. Like their film predecessors, digital cameras come in one of three basic configurations: (1) Fixed lens, (2) fixed lens with zoom or (3) SLR (Single Lens Reflex) – interchangeable lens type. The camera you select depends on your March 2006  9 The Olympus E-300 with the optional twin battery compartment. Many cameras use proprietary batteries which cost many times “standard” cells. But you can’t make a mistake fitting them! camera’s on-board computer. Groups of four RGGB pixels are allocated an average value through interpolation of the values. Once the colour and other parameters of the image are established, the camera’s computer further processes the image to produce a sharp, contrasty, colourful photograph. This provides an enlargement that consumers like – most of the time. Sensor electron flow budget, enthusiasm and the camera magazines you read. Certainly SLRs offer the best quality, with wide zoom range, though fixed lens cameras are available with up to 12 times zoom, plus excellent portability. Digital zoom is a feature in most cameras too but not recommended, as it’s simply digital amplification or enlargement of portion of the image. Increased noise and loss of detail is unavoidable. Besides, you can enlarge a section of an image later in a computer, rather than in the camera. When selecting a digital camera, choose a leading brand like Canon, Olympus, or Nikon, with all the features you want and excellent software to suit your computer. In 2005, the digital SLR camera that accomplished the greatest price versus performance impact was the Olympus E-300. This was made possible by Olympus relocating their manufacturing to China, resulting in a Japanese quality camera at Chinese production prices. How does a digital camera work? Light from the subject is focused in the lens, captured on the sensor, digitally processed by an inbuilt computer for optimum colour, contrast, brightness, clarity and file size, then stored onto a card – all in a second or two. The storage on the card usually accounts for the lion’s share of that time. Firstly, the camera needs to know if there is a colour bias in the light. We 10  Silicon Chip have seen the orange illumination in candlelight or from an open fire but there are other strong colour casts we cannot see so easily, like the green tint in many fluorescent tubes. Digital cameras do a great job of neutralising these unwanted casts, by automatically adjusting to correct the colour temperature. The spectral balance of white light sources is rated numerically by colour temperature. With incandescent lighting, this corresponds roughly to the absolute lamp filament temperature, expressed on the Kelvin (°K) temperature scale. The higher the colour temperature, the more bluish tones while lower colour temperatures have increased reddish tones. Nearly all sensors are the CCD (Charge-Coupled Device) array of light-sensitive elements (often referred to as pixels, which stands for picture elements, the smallest discrete component of an image). Each is covered by an in-register set of filters, one for every element. The filters are red, green and blue, though there are twice as many green filters, as this makes digital images appear sharper, without significantly escalating noise. Light falls on the pixel, causing an electrical charge; the more light, the higher the charge. The charges are transferred down the line of pixels, then the camera reconstructs the electronic image, like painting by numbers. The RGB grid of pixels has digital signal processing applied by the If the RAW setting is used, the image is not boosted or processed at all. This sounds great for professional users but RAW creates very large files, requiring both large in-camera storage and considerable enhancement in a computer. A good compromise for top quality images is to change the camera’s settings to low colour, low contrast and low sharpness. The rationale is that these can be boosted later in the computer but if left at the rather high boost factory settings, it’s near impossible to reverse the effect of the excessive enhancement. Once the image data moves from the sensor and is processed digitally, Digital cameras have reliable auto white balance, with advanced models offering a manual adjustment for precise colour. siliconchip.com.au How the CCD works: light is seen by photodiode ‘pixels’, focussed through individual micro lenses, each with a colour filter. The vertical data transfer channel electron flow reaches the horizontal data transfer channel to exit the CCD. This jumble of electrons is then sorted to a viewable photograph, it’s directed to a buffer memory, then saved to a memory card. With advanced 35mm film cameras, a motor-drive captures action like sports and motor racing. The number of frames of film that can be shot is primarily limited to the speed of the motor-drive and its ability to position the next film frame quickly. Digital cameras don’t have motordrive delays but have an equivalent in the ‘burst-rate’. It is limited by the image processing delay plus latent writing time, both dependent on the file size and the internal memory buffer. To minimise these processing delays, the buffer memory temporarily stores images, allowing more images to be exposed in a continuous burst. If a digital camera is purchased for action photography, the burst rate at full resolution, lag (between pressing the shutter and exposure) and autofocus speed are vital factors. Some digital cameras are impotent when it comes to speed and this can be disastrous to discover after purchase! Many cheaper digitals take as much as a second or more between the time the shutter button is pressed and the time the image is actually “shot”. In candid photography, even half this is plenty of time for the subject to turn their head away or even for someone else to walk into the frame and block it! Burst mode is very useful for photographing in dim light too, as hand- held photography normally results in blurred images. Using the sequential (burst) setting, hold the camera very steady and take a burst of say, six images in rapid succession. Chances are one of the frames will be clear enough to use. Alternatively, in low light situations, place the camera on a tripod and set it to self-timer, just as you would have done with a film camera. This avoids blurring while pushing the shutter-release. The photograph of Above: three of the typical memory cards (there are several others) used in modern digital cameras – all three these days would be regarded as very small capacity (SanDisk, for example, now has a 4GB CompactFlash card available). At right is a table showing the typical file sizes for various qualities of digital image, at various compressions. RAW and uncompressed TIFF files don’t take long to fill even a large card. siliconchip.com.au March 2006  11 Choosing the Athlete mode for most general photography tells the camera to keep to the highest shutter speed possible. This avoids camera shake (blur) in all but the lowest light. the BMW interior (page 14) was taken using this technique. For most photography, the digital camera is best set on autofocus and the athlete symbol. The latter ensures the camera selects the highest shutter speed possible, avoiding camera shake. Lens focal length The overall size of the chip governs the lens’ focal length compared to 35mm film cameras. As many people are very familiar with the older film cameras, focal lengths of digital lenses are often quoted in sizes equivalent to 35mm. For example, a 14mm Olympus digital lens has the same angle of view or lens coverage as a 28mm lens in a 35mm film camera. The need for wider-angle lenses in digital also favorably affects the depth of field – the distance from the nearest to the furthest point of perceived “sharp” focus in a picture. Digital lenses therefore produce images with a greater focus depth and are less prone to camera-shake. Digital camera manufacturers prefer to make digital-specific lenses, rather than adapting 35mm lenses, as they require an optimum light path and must be higher resolution to maintain good clarity on the small sensor area. However, “film” lenses with the same mount and electronic connec- of viewfinder when too close to the subject. Advanced viewfinders show exactly what the camera sees. Through-thelens (TTL) systems display the image in the viewfinder via a prism, flip up mirror, image-splitting or combinations of these. TTL viewfinders can have a disadvantage – on slow shutter speeds or when the photographer is not shielding the viewfinder (like on self-timer), light may enter via the viewfinder, fogging and overexposing images. ‘Band-aid’ solutions supplied by manufacturers include a plastic piece to cover the eyepiece! The mirror viewfinder system has excellent brightness in the viewfinder and near perfect cropping of the intended image. The Olympus E-300 overcame the traditional large bulge at Some SLR cameras can have light enter via the viewfinder in low-light shooting. To avoid fogging, a simple piece of plastic is used to cover the viewfinder. EYECUP tions (eg, for autofocus, auto aperture, etc) can usually be used with a digital camera. Viewfinders & mirrors The viewfinder may be as simple as a hole in the camera body, with lenses to look through. Parallax (out of alignment) errors occur in this type EYEPIECE COVER the top of the viewfinder by designing a mirror that flips sideways. When SLR lenses are changed, there’s a real possibility of dust intrusion onto the mirror, or worse, the sensor. Olympus all but eliminated dust contamination by an ultrasonic cleaning burst every time the camera is switched on. This high tech solu- Left: photo before adjustment showing histogram levels settings. Right: improved Photo after levels adjustments. 12  Silicon Chip siliconchip.com.au Left: high resolution image. Centre: low resolution image (note loss of clarity and increased noise); and right: highly compressed JPEG (note compression artifacts) tion is mated with a low tech ‘bin’ for the dust – an adhesive strip below the sensor! The adhesive strip is replaced when the camera is serviced. With SLRs, it’s also possible to have dust land on the mirror or rear lens element. Both intrusions look enormous, as they are so large compared to the image. If you see a foreign body through the viewfinder and it’s not on the photographs or viewfinder, then the dust is on the mirror and easily blown away. A camera hurricane lens blower is very useful for dust, though if it comes with a hair brush, discard the brush, as it’s a dust collector and can also easily place grime onto the lens. Another TTL viewfinder utilises a micro LCD ‘monitor’ screen. Some reviewers protest it’s difficult to focus with this low-resolution system. Most photographers soon adapt, especially as autofocus is very accurate and the image is viewable in any light. With or without glasses, photographers’ vision varies greatly, so many viewfinders have a variable diopter wheel. This enables the user to adjust the viewfinder preset focus to suit their eyesight. A popular viewer is the LCD screen on the back of the camera, backlit by a fluorescent tube. This can be very difficult to see in sunlight or even bright daylight. To remedy this, some LCDs display a much brighter image but the highlights, shadow detail and contrast are not WYSIWYG (What You See Is What You Get), so it only has limited value. The digital camera shutter is electronic. As a consequence, the camera is so silent, photographers can switch on a simulated shutter noise on some models! This is not as absurd as it sounds, as it confirms a photograph has indeed been exposed, especially when image processing is slowing photography down. Many cameras have settings like sepia or black and white. Using these settings reduces your options, as colour images can always be converted in a computer. But if they are exposed as sepia, the colour cannot be recovered later. RGB vs CMYK Regardless, all digital camera images are exposed as RGB (Red, Green, Black), as used in television and computer screens. Magazines, leaflets, etc are printed in four colours – CMYK (Cyan = a mid blue), Magenta (deep pink), Yellow and blacK. Conversion from RGB to CMYK in an application such as Photoshop requires experience, as the auto conversion in many graphics applications is not perfect. Look at photographs in a number of digital camera magazines and you’ll soon see mauve skies – the most common conversion error. Image brightness range can be depicted as a histogram, or graph of the light levels from the deepest shadows, to the brightest highlights. These image characteristics are important for optimum contrast, plus highlight and shadow detail in prints and are adjustable in graphics applications like Photoshop or Photoshop Elements. While there are other applications offering the same (or similar) control, Photoshop has become the industry standard for image manipulation and adjustment so for simplicity we will refer to Photoshop throughout this article. The many colour adjustment controls in Photoshop can be used to restore old colour photographs too. In the 70s, processing labs introduced fast machines. Over 30 years later, we find the speedy processing of the Fast film processing in the 70s was not light-fast, so they often have a highly magenta (pink) cast now. Photoshop can restore these images. siliconchip.com.au March 2006  13 than film or digital cameras. Astounding shadow detail can be recovered in many digital photographs but overall, nothing is superior to proper exposure. Photographs taken in medium to high contrast situations like sunny days have whites and dark areas with no detail. This is incompatible with printing enlargements, leaflets and magazines, where a narrow contrast range with detail in the light and dark areas is mandatory. If there is no detail in the white areas, for example, the printing press will not lay down any ink at all and the image will appear blotchy, as if it hasn’t printed correctly. Therefore most commercial printers like to see a contrast range of around 10%-90% or even 15%-85%, where 0% is white and 100% is black. To avoid excessive, unprintable contrast, one or both of these remedies can be utilised: (1) set the camera to low contrast and/or (2) make a double or triple exposure with images from too light to too dark. The different exposures can be aligned on top of each other as layers in Photoshop and then the extreme exposures removed with the eraser. Storage A higher resolution or wider angle of view is achieved by overlapping a number of images. In this case, three were overlapped to fit the entire scene. era was not light-fast and nearly all the images are barely recognisable through an immense magenta (pink) cast. Computer graphics software can help recover the missing colour. In Photoshop, there are a number of other methods available to improve image colour and brightness, like ‘variations’ and ‘curves’ plus external add-ons, called ‘plug-ins’. A popular plug-in is onOne Intellihance (formerly Extensis). The image sensor output is rated according to the number of effective pixels in the image resolution. For example, 8MP is eight million pixels. This pixel density or resolution influences the clarity, ‘grain’ or degree of magnification possible before noise and artifacts are seen. Artifacts are groups of pixels or unwanted noise, only seen under extreme magnification. For static subjects, it’s possible to achieve much higher resolution than the camera delivers by overlapping two or three exposures. The image at left is three 20Mb sections, joined and overlapped to make a true 60 Mb image. The collage was especially needed, as even the widest lens would not fit the scene in. The downside? For perfect results, enormous computer time is needed to match the sections, as optical distortion ensures they never fit together perfectly. A tip: when copying flat objects or documents to A4 size, don’t forget a flatbed scanner still has a higher resolution 14  Silicon Chip Image storage cards vary with camera brands. Popular types include CompactFlash (CF), SmartMedia/MMC, MemoryStick, etc. They are completely solid-state and are usually very reliable. There are also MicroDrives, which usually offer significantly more storage but have microscopic moving parts and are sensitive to magnetic fields, so they can be less reliable – but follow a few precautions and they rarely have problems. Cameras and memory systems are not infallible, so error messages are possible. If a memory card cannot be read, remedies are: (1) Turn off the camera and remove the card. Check for dust and fingerprints. Try again. (2) Put fresh batteries in the camera. (3) Try the card in another camera, at a photo lab or in a card reader. (4) Reformat (not erase) the card. This will wipe all images but most times saves a reoccurrence of the problem; or (5) Send the card to a data recovery specialist – the most expensive option. For image recovery software – see the article at www. aaa1.biz/sc.html The best insurance is to frequently save images you cannot Cameras and printing processes often cannot handle the range of density, from white to black detail, so taking three different exposures, from too light to too dark, then merging the best exposures in Photoshop results in a printable image. siliconchip.com.au afford to lose onto a computer and leading brand CDs – preferably more than one CD, if the images are vital. Digital cameras (and especially their LCD monitors) are power-hungry, so batteries are a premium item. Startling developments have been made in battery capacity and camera power conservation. Rechargeable batteries are almost essential and should be rated at least 2,000mAh. If they are used and recharged regularly, they will last for years, at a cost of just cents per ‘film’. Photographers can take measures to help a set of batteries last all day: set the LCD image preview off, or to just a five second glimpse (you can always manually recall the image and look at it longer), plus auto revert to standby mode after just a few minutes. Batteries can be very expensive, so consider aftermarket batteries from SILICON CHIP advertisers. But that’s not always possible: the Olympus E-300 SLR, for example, has a unique-shape 7.2 V lithium ion battery with a 1,500 mAh capacity, so owners are forced to spend about $200 for a battery that has a capacity similar to a set of AA rechargeables selling for less than $30! The plus side is their ease of use due to the keyway shape, enabling batteries to be loaded in even the lowest light. A number of sets of reliable rechargeable batteries and a regular recharging routine ensures you are always ready to take digital photographs. If you’re travelling and taking a notebook computer with you to download to, consider using a charger which plugs into the USB port, saving taking the camera charger with you. An alternative to taking the notebook is one of the self-contained mini hard drive/card readers, designed specifically for saving lots of images to. A tip: whenever you can, save the contents of any hard drive (notebook or self-contained) to CD/DVD (even multi copies), especially if the images are irreplaceable. While it’s now possible to take a set of images and deliver the card for processing, the ultimate is enhancing images yourself with creative work on a computer. If you are considering digital photography, factors include: Will it be better or more convenient than a film camera? Is the increased time needed to enhance in the computer taken into consideration? What resolution (megapixels) are needed to suit the enlargements that may be required? How fast is the camera – the lag time, shooting speed and delays for writing? Is the extra price vs. convenience worth it? What about the future? Nikon announced recently that it is ceasing most film camera and associated lens production; other manufacturers have/will follow suit. On the flipside, Konica-Minolta has announced that it is pulling out of digital camera market altogether after suffering huge losses. Some experts are tipping that 35mm film as we know it will be all but unobtainable in just ten years; not to mention processing availability. Digital cameras are a revolution embraced by many, but film/processing is still an option – for now! References and further reading: www.aaa1.biz/sc.html NEXT MONTH: We’ll look at some of the hardware required and some of the traps for young players . . . siliconchip.com.au March 2006  15 The World’s Most Highly Hybrid Petrol/Elec Only a complete fruit-loop would modify a car with no less than six Electronic Control Units, a 288V battery, two electric motor/generators and a control system that frequently switches off the engine, incorporates regenerative braking and uses electronic throttle control. Well, welcome to that car – and the crazy modifier, regular SILICON CHIP contributor Julian Edgar. F or fifteen years, modifying cars has been my passion. I’ve run 21 psi boost on a 3-cylinder Daihatsu Mira, rebuilt a BMW 3.0si engine and played with cars as diverse as a V8 Lexus LS400 and a turbo Nissan Maxima V6. For the last decade or so it’s been not only a hobby but also a livelihood – over that period I’ve worked full-time for both automotive print and performance on-line magazines. But a few years ago I started getting bored. After all, there’s only so many cars fitted with huge turbos or even bigger exhausts you can feel excited about. I’d seen it all before – and it no longer thrilled. Then I came across a 16  Silicon Chip hybrid Toyota Prius at a price I couldn’t go past. A grey market Japanese import, it was the very first domestic Japanese model. Compared with the two Prius models sold new in Australia (see the Prius Models panel), it had less engine and electric power but it was still a full hybrid petrol/electric car. Here was a car I could really get my modification teeth into – literally anything I did would be cutting edge, never done by anyone else in the world. Forget ringing up the local workshop to ask what turbo size would be suitable; don’t bother joining an on-line discussion group to find out what flow injectors are fitted; siliconchip.com.au y Modified ctric Car Prius Models So what are the di fferent Prius mod els? Julian Edgar’s model, the NHW 10 (pictured at le ft), was released Japan in late 1997 in . It uses a 43kW pe trol engine and ha 30kW of electric s power available. The first model Pr ius sold outside NHW11 model wh of Japan was th e ich looks the sam e as the NHW10 has some signific but ant changes, inclu ding engine powe increased to 53kW r and electric powe r increased to 33kW The current mod el, the NHW20, . has both a new and although the body fundamentals re main the same, more significant even driveline change s. Engine power ha s increased to 57 kW and electric po er is up to 50kW. wThe NHW20 has been selling well in Australia and ar both ound the world, es pecially in the US . in a reduced intake charge. So despite the geometric compression ratio of the Prius being a sky-high 13.5:1, the cylinder pressures on the compression stroke don’t really reflect this. This approach benefits efficiency because at lower loads, the throttle is open wider for a given power output, so reducing pumping losses. To allow the degree of ‘Atkinsoning’ to be altered on the fly, the engine Electronic Control Unit (ECU) alters intake valve cam timing. The other vital ingredient in making this process work is the use of an ECU-controlled electronic throttle. In this car, the driver’s torque request often has little to do with the actual throttle angle selected by the ECU! Atkinson Cycle (sometimes called Miller Cycle) engines have low-RPM torque. But in the Prius, there’s a dirty great big 30kW AC electric motor ready to provide maximum torque at zero road speed. Two motor generators don’t worry about looking around for off-the-shelf electronic aftermarket parts. I wanted a challenge – and this was certainly it. Prius driveline The Prius uses a 1.5-litre 4-cylinder engine closely related to the engine used in the Toyota Echo/Yaris. However, it has much less power than the Echo – just 43kW. The low power output is because the engine revs to only 4000 RPM and uses what is called an Atkinson Cycle. Compared with the conventional Otto Cycle, an Atkinson Cycle engine delays the intake valve opening time, resulting siliconchip.com.au In fact, the gearbox (called the Power Split Device or PSD) actually contains two electric motor/generators. Along with the engine, these are connected to an epicyclic gear train. The engine’s output is split between the wheels and one of the generators. The generator charges the high voltage battery or alternatively, feeds the other electric motor that in turn helps drive the wheels. This electric motor can also receive power from the high-voltage battery to either assist the petrol engine or propel the car on its own. The PSD’s gear ratio is a result of the balance between the speeds of the engine, the electric motor/generators and the wheels and that depends on how much force is applied by each. This gives the effect of a continuously variable transmission. One of the electric motors also acts as a quiet and powerful starter for the engine, allowing it to be stopped and started smoothly as needed. The other generator is used to regeneratively recover energy from the car during braking and store it in the battery for later use. When the driver lifts the accelerator pedal, the engine’s fuel supply is cut off. For more on Prius technology, see the December 2001 issue of SILICON CHIP. Modifying the regenerative braking One of the first electronic modifications I performed was to increase the amount of braking regeneration. March 2006  17 To keep the Prius feeling as conventional as possible, both the regen and conventional brakes are controlled by the one brake pedal. In the first part of its travel, the brake pedal operates the regen brakes alone and as further pressure is placed on the pedal, the friction brakes also come into play. However, the regen braking in the Prius didn’t seem particularly strong. That may be because I had installed rear disc brakes and was running high-performance Kevlar brake pads with slotted discs front and back – perhaps the hydraulic brakes were doing more work than had been intended by the designers. The central colour LCD in the dash shows by means of small ‘sun’ symbols how much regen has occurred each five minutes, with each sun indicating a regen of 50 watthours. But in my driving, seeing a lot of suns was rare – so it seemed to me that if the regen could be tweaked to do a greater proportion of the braking work (especially in light braking), fuel economy would benefit and the braking would be smoother. The ABS ECU handles regen braking, sending a signal to the hybrid ECU to tell it how much regen to impose. But how does the ABS ECU know what to do? Rather than measuring brake pedal travel (which could vary with pad wear, etc), the system uses sensors to detect master cylinder pressure – the higher the master cylinder pressure, the harder the driver is pushing on the brake pedal. If the pedal pressure is low, the ECU knows that the driver wants only gentle deceleration and so instructs the hybrid ECU to apply only a small amount of regen. However, as master cylinder pressure increases, so does the amount of regen that can be automatically applied. If the amount of regen that occurs is largely dictated by the output of the master cylinder pressure sensor, why not intercept and alter this signal? That way, the ABS ECU will think that there is more master cylinder pressure than is actually occurring, so resulting in more regen being applied. Since the actual hydraulic pressure going to the brakes is unchanged, there’ll be a greater proportion of regen braking in the mix. The voltage output of the pressure sensor ranges from about 0.4-3V, rising with increasing pressure. So if a small voltage was added to this signal, the ECU should respond with more regen braking. But would the ECU detect a fault condition? The workshop Fig.1: this circuit that initially used to alter the amount of regenerative braking. A 100kW pot was wired between the output of the sensor and the regulated 5V supply, allowing the signal to be increased in voltage. To give the required fine adjustment, a multi-turn pot was used. Note: the ABS ECU has many more wiring connections than are shown in this diagram! 18  Silicon Chip A colour LCD in the middle of the dash can be configured to show economy (measured in kilometres per litre in five minute increments) and the amount of braking regeneration that has occurred. Here it can be seen that over the last 30 minutes economy has never dropped below 20 kilometres/litre (that’s 5 litres/100 km) and that 150 watt/hours of regeneration has occurred. Being driven enthusiastically and with some hard country road hillclimbing thrown in, economy of the modified car averages in the high fives in litres/100 km. manual states that a fault will be detected if the voltage from the sensor is outside the range of 0.14-4.4V, or if it is outside a certain ratio to its nominally 5V supply voltage. Further, the latter is checked when the brake switch is off (ie, brake pedal is lifted). In other words, the voltage needs to be within a certain range and in some cases this is checked with the brake pedal not activated. Fig.1 shows the circuit that was initially used. A 100kW multi-turn pot was wired between the output of the sensor and the regulated 5V supply rail, with the wiper of the pot connected to the original ECU input. However, this circuit did not take into account the selfchecking by the ECU of the input signal with the brakes not applied. Fig.2 shows how a relay was wired into the circuit so that the pot was bypassed whenever the brake pedal was Fig.2: the circuit shown in Fig.1 did not take into account the self-checking by the ECU of the input signal without the brakes applied. This diagram shows how a relay was wired into the circuit so that the pot was bypassed whenever the brake pedal was released. siliconchip.com.au released. At very light pedal brake pressure, this modification has caused the voltage at the ECU input to be lifted from 1V to about 1.15V. This results in clearly stronger deceleration when the pedal is lightly pressed and much stronger regen than normal as the pedal is pressed harder. At high braking efforts, the behaviour of the car is near standard – it’s in very light braking where there’s a clear difference. And the amount of regen now occurring? The regen braking is clearly doing much more of the braking work. This can be both seen in the display of watt-hours regenerated (there are more suns appearing) and also in the feel of the car. The regen braking is smooth and effortless, slowing the car substantially before the brake pedal is moved a little further to activate the hydraulic brakes and bring the car to a halt. It’s hard to assess overall urban fuel consumption, but in some 5-minute increments, it has improved by 30%. Intercooled turbo On the road, the Prius doesn’t feel particularly slow, despite its low power and 1240kg mass. The electric motor’s low-speed torque and petrol engine integrate seamlessly, giving punchy performance in all but one driving situation. That situation is climbing a long, steep country road hill. Initial performance is fine but after a while, the high voltage battery becomes drained, decreasing the amount of electric power available. The car slows, the engine revs automatically increase, and you can find yourself with the accelerator pedal flat to the floor, just crawling along. At this point a rather cute tortoise symbol lights up on the dash – we christened her ‘Myrtle the Turtle’. And it just so happens that I live at the top of a long, country road hill that has gradients as steep as 16% – and Myrtle is a real pest. By feathering the throttle and watching the movement of current in and out of the HV battery (the colour LCD shows this), it was possible to negotiate this hill with a speed over the crest of 55km/h or so. But lose concentration and that dropped to 47km/h. That’s awfully slow. (It should be stressed that the later model Prius cars don’t suffer from this hill-climbing problem.) I considered adding another HV battery pack but because of their control systems, this is an extremely complex move – nothing like as simple as wiring the two batteries in parallel. That left increasing engine power as the best option and so I turbocharged and intercooled the engine. And then the fun started…. Fascinatingly, the hybrid control system coped with the increased power remarkably well. Presumably because Toyota’s engineers could never predict exactly how much power the petrol engine would generate (as with all engines, this varies with atmospheric conditions, individual engine build quality and so on), the hybrid system had enough flexibility in its control system to direct any excess power being developed by the engine into charging the HV battery. Note: into the HV battery, not to the wheels… So the odd situation developed where, with the HV battery level at (say) half, the performance of the car was standard – despite the turbo! But what about up the big hill? Ah, well there the car was transformed. Rather than the HV battery dropping in charge, going up the hill it actually From the publishers of SILICON CHIP PERFORMANCE ELECTRONICS FOR CARS NOT A REPRINT: More than 160 pages of new and exciting projects never published before – all designed to get top performance from your car. FASCINATING ARTICLES: 7 chapters explaining your car – engine management, car electronics systems, etc ADVANCED PROJECTS: You’ll build controllers for turbo boost, nitrous, fuel injection and much more! We explain the why as well as the how to! Available direct from the Publisher ($22.50 inc postage): Silicon Chip Publications, PO Box 139, Collaroy NSW 2097. Ph (02) 9939 3295; Fax (02) 9939 2648; email silchip<at>siliconchip.com.au or via our website: www.siliconchip.com.au siliconchip.com.au March 2006  19 A thick-walled exhaust manifold was fabricated to locate and direct exhaust flow to the added turbocharger. The mechanical addition of the turbocharger was relatively straightforward – it was getting the air/fuel ratio suitable for the forced aspiration that caused Julian Edgar to pull out his hair…. increased in charge! And always having lots of battery voltage – and so electric motor power – resulted in the speed over the crest of the hill increasing from a low of 47km/h to a stunning 86km/h. But let’s go back a little. When the turbo was fitted, the air/fuel ratios needed to be changed – a turbocharged engine (especially one with a 13.5: 1 static compression ratio, Atkinson or no Atkinson) needs richer than standard mixtures. The Prius uses an air/fuel ratio of 14.7:1 all the time – the engine ECU monitors the output of the two oxygen sensors to constantly hold this air/fuel ratio. So how to change this? The first step was to fit a Digital Fuel Adjuster (from “SILICON CHIP’s Performance Electronics for Cars”) to allow alteration of the airflow meter output. However, monitoring the mixtures with a MoTeC air/ fuel ratio meter showed that the Prius ECU is extraordi- The Prius airflow meter sensing element is normally built into the airbox. With the addition of a turbo, the standard airbox could no longer be fitted and so the airflow meter sensing assembly was removed and built into this new, larger airflow meter. The SILICON CHIP Digital Fuel Adjuster (DFA) was then used to correct the output signal. 20  Silicon Chip To provide the additional fuel required for the turbo, a dual-pressure fuel system was installed. This uses two pumps, two pressure regulators and a solenoid to switch from low to high fuel pressure. The switching is done by a SILICON CHIP Simple Voltage Switch that monitors airflow meter output voltage. When load rises sufficiently, the fuel pressure is switched high and at the same time, the twin oxygen sensors are disconnected. This approach prevents the engine Electronic Control Unit ‘learning around’ the changed mixtures. narily quick at learning around any changes made in this way. Alter the mixtures to 12.5:1 and within five or so seconds, the mixtures are back at 14.7:1! The same thing occurs if fuel pressure is increased – back go the mixtures to stoichiometric. Hmmm, so what about disconnecting the oxy sensors, substituting an appropriate looking 0-1V square wave signal on the ECU oxy sensor inputs and then altering the airflow meter output voltage? A pair of 555-based circuits was constructed and the system wired-up. But the ECU immediately picked that something was wrong with the oxy sensors and went into a default mode – which with the added airflow of the turbo, resulted in mixtures even leaner than 14.7:1! Aaaaagh. Well then, what about disconnecting the oxy sensors (easily achieved just on high load with the “Simple Voltage Switch” [also from SILICON CHIP Performance Electronics This 555-based circuit was built in an attempt to simulate the fluctuations in oxygen sensor voltage normally seen by the Electronic Control Unit (ECU). If successful, this would allow the oxy sensors to be disconnected, stopping the ECU learning around mixture changes. However, the ECU immediately saw through the pretence, outputting the same mixtures as when there is no oxy sensor input at all. siliconchip.com.au These logged traces compare the input and output of the brake pressure modification circuit. As can be seen, the output trace shows a lot more ‘area under the curve’, indicative of a higher brake pressure being monitored by the Electronic Control Unit. The result is increased regenerative braking which improves economy and reduces friction brake wear. for Cars] working off the airflow meter output voltage) and then using the Digital Fuel Adjuster (DFA) to alter the mixtures? Again, no success – and this time, the mixtures appeared to vary randomly. About this time I upgraded the fuel system with a new in-tank pump, external adjustable pressure regulator and a return-line to the tank. That allowed me to run higher fuel pressure (which initially gave correct mixtures with the oxy sensors disconnected) with the DFA used to tweak the resulting mixtures. But, yet again, the mixtures were not consistent. After many weeks of work, I finally devised an effective system. Two fuel pumps and two fuel pressure regulators are used to allow the running of two different fuel pressures. A solenoid allows electronic switching between the two different pressures. The lower of the two pressures is set so that, even when running a little turbo boost, the ECU can keep the mixtures at 14.7:1 and the oxy sensor feedback loop operates as normal. Then, when a preset load is reached, a Simple Voltage Switch monitoring the airflow meter voltage switches out the oxy sensors and activates the solenoid increase in fuel pressure. The resulting mixtures are then fine-tuned by a DFA working on the airflow meter output. With this approach, the mixtures are consistent and economical (the car is still in closed loop with 14.7:1 mixtures for the vast majority of the time) but with appropriately rich mixtures used at full turbo boost. (Incidentally, ignition timing has never been a problem. I have never heard the engine detonate, even when [briefly!] running 15 psi boost. 95 octane fuel is used – the car is designed to run on 91.) Auto throttle shutdown About this stage I started to relax. Ahhh, this is nice...the world’s only turbocharged, intercooled Prius with modified regen braking. Those many hours of work were well worth it. And that was the case until I discovered that the hybrid control system’s adoption of turbo power wasn’t as seamless as I’d first thought. Initially, I’d decided the abrupt engine shut-down that occasionally occurred at full power was an ignition problem – and had replaced the spark plugs with a colder heat-range Iridium design. siliconchip.com.au March 2006  21 But then, while watching the boost gauge, I saw what was happening. At full power, the hybrid system would momentarily close the electronic throttle. Whether that’s to protect one or both of the electric motor/generators – or for some other reason – I still don’t know. But the result was a huge power loss perfectly timed to occur when overtaking a semi-trailer…. If the shutdown was a result of excessive engine power, I could just drop turbo boost at higher revs. But the problem was that I couldn’t. The waste gate spring pressure on the turbo meant that 7 psi was as low as I could go. But there had to be another way of dropping boost – and there was. By using a solenoid to control the boost pressure feed to a recirculating blow-off valve, the valve could be made to leak, bleeding boost from the compressor outlet back to the inlet. The result is decreased boost. I initially used the Performance Electronics for Cars Independent Electronic Boost Control (IEBC) to achieve this function but ran into a snag. The IEBC allows the mapping of a pulse-width controlled solenoid on the basis of engine load, as measured by injector duty cycle. However, it doesn’t have an adjustable hysteresis function and so the solenoid would close (causing the blow-off valve to open) and then as a result of the lower boost, engine load would drop, thus switching the solenoid back on! Boost would then surge up and down. (This isn’t normally a problem with the IEBC because the slope of the adjustment curve can be made gentle. But in the case of the Prius, it had to be a much more sudden change.) The answer was to (again!) use that most ubiquitous of building blocks, the Simple Voltage Switch. With its adjustable hysteresis, it was ideal in this application, wired-in to monitor airflow meter output signal. As finally configured, boost rises to 7 psi and then above the preset load point, smoothly drops to 4 psi. This makes no difference to on-road performance – and there are no throttle shut-downs! Auto engine off While compared with many turbo applications the Prius turbo is not working particularly hard, there is one characteristic of its hybrid control that if left unaddressed, could quickly kill the turbo bearing. As described earlier, when the throttle is lifted, fuel flow to the engine is stopped. So, approaching a red traffic light, the engine stops running as soon as you back off – and stays off until the lights go green and you apply the accelerator. A turbocharger relies on engine oil flow for lubrication and partly for cooling, and so the engine should not be turned off until the turbo has had time to cool. If the turbo has been spinning hard, an early engine switch-off can cause oil in the turbo bearing to coke. So how could the Prius petrol engine be kept running after a boost event? This model Prius has two air-conditioning modes. In High mode, the engine is forced to run continuously. In Normal mode, the engine is allowed to switch off whenever the hybrid ECU decides it should be off. When High mode is selected, the air-con system tells the hybrid ECU that it should not switch off the engine by means of an ‘engine on’ request signal. This signal is very simple – above 4V means keep the engine running, below 1V means it’s OK to switch it off. 22  Silicon Chip To prevent the hybrid control system automatically switching off the petrol engine shortly after the turbo has been on boost – and so starving it of oil – a Simple Voltage Switch was modified to provide the ‘engine on’ request signal than normally occurs when the air-conditioner is switched to high. This photograph shows the new MOSFET, capacitor, diode and resistor that allows the Simple Voltage Switch to feed the correct signal to the hybrid ECU for 30 seconds after the turbo has been boosting. So by feeding 5V to the ‘engine on’ input of the hybrid ECU, the engine can be kept running. Yet another Simple Voltage Switch was used to monitor the airflow meter signal, sensing when engine load was above a certain threshold that corresponded to a few psi of boost. To derive the required 5V signal to feed to the hybrid ECU, a pot was placed across the regulated 8V supply used in the Simple Voltage Switch. The Simple Voltage Switch was then modified so that once it was triggered, it stayed on for about 30 seconds. So how well does the system work? In most cases the delayed ‘on’ time for engine running isn’t noticeable – when the car is moving, it’s hard to tell whether the engine is firing or not. But if the car is being driven hard around the city, pulling-up at a red traffic light causes the engine to keep running for a short time, when previously it would have switched off as soon as the car was slowing for the stop. Conclusion We’ve run out of space to cover all the mods made to the car – they include a rear sway bar, electronically modified electric power steering, on-dash mixture indication, electronically controlled high pressure intercooler water spray, under-floor aerodynamic changes and plenty of other bits and pieces. And the results? Well, the worst aspect of the car was previously its country road hill-climbing ability – and that’s been improved by over 80%! But what about the raison d’etre of the Prius: fuel economy? The modified Prius now has better than standard fuel economy. On an open road cruise at 100km/h, the turbo Prius will turn in a best economy of about 5.5 litres/100km, whereas in the same conditions, the dead standard car used to get about 6.3 litres/100 km. And even when being driven hard, the economy now averages about 5.8 litres/100km. SC siliconchip.com.au ONE ’SCOPE ON W E B TO EACH ! MONTH SUBSCRIBE TO THIS... ...AND YOU COULD WIN THIS! A 20MHz dual trace oscilloscope from Dick Smith Electronics For the next few months#, every reader who takes out a new subscription, or renews an existing subscription, goes into the draw to win a brand spanking new dual-trace 20MHz oscilloscope, as reviewed this month on page 62. It’s valued at $399.00! You could be the envy of all your friends if you had this fine instrument on your workbench. It comes complete with two 10:1 divider probes, enabling you to do all sorts of measurements. You love the magazine. Why not subscribe and save? For a limited time only, we are maintaining the present subscription prices. Subscribe now and beat the price rise later this year. And at the same time, have a great chance at winning this fabulous ’scope! 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Or email the same details to silicon<at>siliconchip.com.au Or log onto siliconchip.com.au and click on “print edition” March 2006  23 Or call (02) 9979 5644 & quote your credit card details SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: dicksmith.com.au A PC-Controlled Burglar Alarm System This month, we complete the construction, describe the test procedure and give the “driving instructions” for the software. We also describe the optional keypad module which can be used to arm & disarm the system. Pt.2: By TRENT JACKSON H AVING COMPLETED construction of the alarm unit, it’s time for the test procedure. At this stage, microcontroller IC1 should be out of its socket and the SLA battery should be disconnected. It’s also a good idea to disconnect the display board from the main control board until the power supply has been checked out. Here’s the step-by-step test procedure: Step 1: apply 16VAC power to the main controller board (but leave SLA battery disconnected). Step 2: set your DMM to read DC volts and check the output from the 12V regulator (REG1). Anywhere from 11.5-12.5V is acceptable. Now, do the same for the 5V regulator (REG2) – its output should be very close to 5V. If either of these readings is drastically low, switch off immediately and check for shorts on the PC board and for polarised components that may be the wrong way around. Step 3: check the voltage across the battery leads (ie, between ZD1’s cathode and D7’s cathode). You should get a reading of 13.6-14V (this is the charging voltage). If this checks out, connect the bat30  Silicon Chip tery and repeat the last step. Depending on the amount of charge in the battery, you should get a reading in the range of 13-13.6V (a flat battery will give a lower reading). Step 4: check that +5V is present on both pins 11 & 32 of the microcontroller’s IC socket. If so, switch off, connect the display board, re-apply power and check that the mains power LED is lit (the other LEDs should all be off). Also, check for a +5V rail on the three righthand pins of the key socket connector on the display board. Step 5: disconnect the power supply and plug the PIC microcontroller (IC1) into its socket. Take care to ensure that pin 1 is at upper right – see Fig.5 in part 1. Step 6: this step checks the basic operation of the two PC boards. First, connect a sensor (PIR or reed switch) to the input of zone 1. As a default, the system assumes that N/O (normally open) sensor contacts will be used. When the sensor is triggered, you should see the status LED for zone 1 illuminate. This LED should then extinguish when the sensor is reset. Repeat this test for the remaining seven zones, checking that their allocated LEDs respond accordingly. Step 7: it’s now time to interface the system to your PC and test the various features. Connect it to the PC via an RS232 serial cable, then install and run the software. Refer to the large “Driving The Software” panel for information on the various software interfaces. Step 8: click on the “Comms” setup button and select the serial port that’s to be used. Now click on the button labelled “Test”. If you have selected the correct port number, you should see all the LEDs on the front of the unit counting up in BCD (binary coded decimal). You should also hear the internal siren briefly chirping in synchronisation with the LEDs. If this doesn’t occur, check that the port is operational and valid. Doublecheck to ensure the integrity of your serial port cable and that the RS232 IC is installed the right way around. Step 9: before proceeding to secure the system with passwords, check the door strike outputs. These are operated through the Arm/Disarm interface. Using your DMM, you should be able to measure 12V across their terminals when activated. Don’t set the duration time for any given strike longer than it really needs to be. They siliconchip.com.au Fig.8: the complete circuit details for the optional keypad module. It’s based on a PIC16F84A microcontroller (IC1) and a standard 3 x 4 matrix keypad. draw high current and the power supply is quite modest. Step 10: click on the arm button for zone 1. The internal siren should briefly chirp and the corresponding “armed” LED should light. Click on the disarm button and check that the LED extinguishes. Step 11: secure the system with passwords and configure the entry/exit delays, siren duration times and autorearming features (if needed). Step 12: this is the fun part – install the alarm into your premises and run the cables to all the sensors. The keypad The keypad is for those who don’t wish to use a computer to arm and disarm the main alarm system. That way, you only need a PC for the initial system set-up and to define parameters and passwords. A keypad is also useful if you want to use the system as a domestic house alarm and don’t need the versatility offered by the Windows-based softsiliconchip.com.au ware. Alternatively, you can build the keypad for emergency use only – ie, to arm and disarm the system in the event of a blackout or computer malfunction. In the latter case, the keypad also lets you do away with the “Hard-Wired Key”, which can be rather inconvenient to use. If the power fails, just plug the keypad in and you’re in business. Furthermore, the keypad can both arm and disarm the system, whereas the “Hard-wired Key” can only disarm the system Up to four passwords can be defined via the Windows software, as shown in one of the screen grabs. However, you don’t have to type in a password for all four – just leave them blank if you don’t require them. Note that to access this feature, you need to be logged in as either an Owner or Admin. These passwords are stored in the PIC microcontroller in the main alarm unit (ie, in EEPROM) and must be four digits in length (numerals only). The star (*) and hash (#) keys are used only to arm and disarm the system. To arm the system, just enter the 4-digit code and press *; to disarm it, enter the 4-digit code and press #. Easy! If the code is correct, a short melody is played. However, if the code is entered incorrectly, then a short series of chirps will be heard. It’s then just a matter of re-entering the correct code but you only get five attempts, after which the system locks you out for 30 minutes. By the way, this unit is quite universal and could easily be adapted to suit a host of other applications. It’s not just suitable for used with the PC-Controlled Alarm. Another PIC Inside the keypad module is – yes, you’ve guessed it – another a PIC microcontroller. This time, it’s a 16F84A and this is teamed with a standard numerical keypad and a handful of minor parts. A vital ingredient is the software March 2006  31 Driving The Software For The PC-Controlled Burglar Alarm T HE SOFTWARE for the PC-Controlled Burglar Alarm has been tested with Windows XP and Windows 98SE but should also work with Windows 95, Windows 98 and Windows 2000. It’s separated into seven main sections to make it easy to drive: (1) Access Control; (2) Log On/Off; (3) Comms Setup; (4) Zone Configuration; (5) System Logging; (6) Entry/Exit Delays and Arm/Disarm. The main GUI is shown immediately below. The software assumes no security until an owner password is created. If you have just loaded the software and want to test the unit before finalising access settings, you can just basically go straight to the Communications Setup window to begin testing. Select the Comm port that you wish to use, then cover your ears and click on the relevant Test button (see GUI below right). The internal siren should sound and all of the LEDs on the front panel should start counting up in binary. If this occurs, then there’s a good chance that your new alarm system is ready for installation. Before doing so, however, it would be a good idea to check that all the zones can be armed and disarmed. THIS IS THE MAIN GUI for the Windows-base software. It’s divided into seven sections (no confusing drop-down menus to explore), which makes it really easy to drive. Clicking on each of these sections brings up the various other configuration panels shown on these pages but first you have to define the various users and set-up access control as shown in the GUI at the bottom of this page. Once you have the system setup, you arm or disarm the system by simply logging on and clicking the Arm/Disarm section to bring up the GUI on the facing page. It’s then just a matter of clicking the Arm or Disarm button for each Zone, as appropriate – or you can arm or disarm all zones simultaneously. THE COMMUNICATIONS SETUP screen allows you to define the RS232 ports that you wish to use to communicate with the PC and the (optional) modem dialler. Make sure that you don’t include any spaces in the phone number string. The two Test buttons help you choose the correct serial ports on the PC and to diagnose faults – see text. PASSWORDS CAN BE alphanum­er­ic in which case you have to use a PC keyboard to log on. Alternatively, if the password has numerals only, you can enter it by clicking the numbers on the virtual keypad shown here. THE FIRST STEP IN SETTING UP THE ACCESS CONTROL for the system is to create an “Owner” user name & password. This is done by keying in a name and password, then selecting the “Owner” option and clicking the “Add” button. Doing that gives you control over the entire system. However, you cannot do much unless you log on. To do that, click the “Log ON” button at bottom right and key in the password that you just set up. If the password is valid you will be greeted with a MSG box that says “Hi”. You can create up to four Owners, eight Admins and 16 Users. Owners can create or delete other Owners, Admins and Users, while Admins can create and delete Users only. Users have defined access level privileges, most of which are selfexplanatory. 32  Silicon Chip siliconchip.com.au ABOVE: THIS IS WHAT THE “ARMING & DISARMING” GUI looks like. You need to have Owner or Admin access to modify these settings. Auto Rearm does exactly what it states – after a preset time, a zone that’s been disarmed automatically rearms itself. This could be useful for monitoring an entrance way, for example, and keeping a log of people who have entered (or left) a building. Note that you can give each zone a label value (eg, “Kitchen”, “Lounge Room”, etc). There are lots to choose from, so that you can easily identify zones. Clicking the “OK” button saves any new settings. The virtual red LEDs next to the Disarm buttons clearly indicate which sectors have been armed. When you arm or disarm a zone, you will hear the internal siren briefly chirp to indicate success. You can also arm/disarm all zones simultaneously. Finally, the Door Strikes buttons at the bottom allow Owners, Admins or Users with defined access to operate the door strikes. Five seconds should be more than ample time for the strike to be activated but you can adjust this value if you wish. THE CONFIGURATION GUI allows you to specify the sensors to be used for each zone – ie, either normally open (N/O) or normally closed (N/C). The status LEDs indicate the condition of each zone. When a zone is triggered, its corresponding LED lights up. This GUI also allows you to set up the keypad codes and shows the config­ uration for the “Hard Wired Key”. You simply select the BCD code and the number of inserts required and the accompanying diagram shows the wiring for the D9 connector. Make sure that the system is plugged into your PC’s serial port before clicking the “OK” button, so that the settings are saved to the PIC’s EEPROM. siliconchip.com.au THE ENTRY/EXIT DELAYS GUI lets you customise the delay settings for each zone (0-255s). As with other settings, these delay times are saved in the PIC, so that the system can be operated without a PC if necessary after set-up (although you do lose features). By default a tripped zone is automat­ i cally rearmed 30 seconds after the siren times out. You can set the maximum number of “rearms” to anywhere between 0 and 9, so that a zone will eventually be locked out after repeated triggerings (eg, to guard against a faulty sensor). Check the noise pollution laws for your state before implementing this feature. Set this value to 0 if you want each zone to be locked out immediately after it has been triggered. THE WIRING DIAGRAM in the Configuration GUI shows you how to wire the Hard Wired Key for a given BCD code and number of inserts. March 2006  33 The data logger records all activity from people logging onto the system, as well as which zones have been triggered and the alarm conditions. To gain access to this screen you must have Owner, Admin or set user level privileges. Each time the software loads, the data log loads as well. It’s then automatically saved at a specified interval. This arrangement means that you don’t have to worry about power failures or having to manually save the logs each time you power down the PC. However, you still have the freedom to manually load and save logs. Up to 2000 samples can be stored which should be more than enough. that’s programmed into the PIC. This software monitors the key presses and produces a serial data stream which is then fed to the PIC microcontroller inside the alarm unit. This in turn scans its passwords database and if it finds a match, allows access to the system. The keypad is perfectly standard – you just press the digits, hit the hash key and the PIC microcontroller spits the digits out serially at 2400 baud. Pressing the hash key inserts CHR$(66) at the start of the data string, while pressing the star key results in CHR$(88) being sent first. This instructs the alarm to either disarm or to arm, respectively. After the function BYTE, the 4-digit code follows in a plain ASCII format. A few minutes of experimenting will allow people with relatively modest PICAXE experience to interface it to their own projects. Automatic resetting Another feature of the keypad module includes automatic resetting if it’s at idle. This simply means that if you don’t press in each subsequent digit There are just a few wire links inside the “HardWired Key” and the software shows you how to wire it. Note that when using this key, you must allow at least a one second time frame between each insertion and withdrawal. If the time frame is too great, the system will lock out for a short period. 34  Silicon Chip in the code sequence within four seconds, the system resets and you have to start over again. This is done to ensure security – ie, it ensures that you have to key in your complete password every time you want to arm or disarm the system. A piezo transducer and a red LED provide audible and visual indication of keypad activity. Each time a digit is pressed, a “chirp” is produced by the transducer. Other sounds are also produced by transducer, depending on the status of the keypad (eg, to indicate correct or incorrect codes). In use, the unit plugs directly into the D9 female socket on the alarm to establish the communications link. In addition, a +5V rail to power the unit is also obtained from the D9 socket. You can plug the unit into the D9 socket (and unplug it) with power applied. However, don’t swap between the PC’s serial port and the keypad port while the Windows-based software is running, otherwise the alarm system may lock up. If it does, you’ll have to reset the alarm by removing all power to it (including the back-up battery). Note: you can “hot-swap” from the keypad to the PC and vice versa if the Windowsbased software is showing the main menu GUI only, or is not running. How it works Fig.8 shows the complete circuit details for the keypad module. As stated, it’s based on a PIC16F84A microcontroller (IC1) and a standard 3 x 4 matrix keypad. The keypad rows are monitored via ports RA3, RB3, RB2 & RB0, while the columns connect to ports RB1, RA2 & RA4. The latter three ports (ie, to the columns) are all set as outputs and are switched at a rate of about 100Hz “total cycle time” – ie, each port is toggled from high to low about 33 times a second. RA3, RB3, RB2 & RB0 (which monitor the rows) are all configured as inputs. These are all normally pulled high to +5V via 100kW resistors, to ensure they don’t “float”. In addition, a 2.2kW resistor is connected to RA4 due to the fact that this pin can sink but not source current. In operation, IC1 pulls each of the columns low in turn and checks for key presses on the rows. For example, if RA2 is low and digit 5 is pressed, the RB3 will be pulled low. IC1 decodes siliconchip.com.au Fig.9: follow this diagram and the photo above to build the keypad unit. The external connections from the PC board are all made via pin headers and connectors. these key presses and produces a digital data stream at its RA1 port. This information is then fed via the D9 connector to port RC3 of the PIC microcontroller inside the main alarm unit. If the password is correct, RA0 on IC1 is briefly toggled high for about 200ms, LED1 flashes and the piezo transducer plays a short “melody” to acknowledge that the correct code has been entered. Note that there are two very distinct “melodies” – one for a valid password and one for an invalid one. LED1 and the piezo transducer are switched on and off via Q1, which is in turn controlled by port RB5 on IC1 via a 4.7kW base resistor (this sets the nector on the display board, inside the main unit. This connects to pin 1 on the D9 socket (note: you will have to make this connection inside the main alarm unit). A 10mF electrolytic capacitor and a 100nF MKT capacitor provide a modest degree of filtering for the supply rail. Finally, IC1 is clocked at 4MHz, as set by crystal X1. The two associated base current to just under 1mA). Assuming that the beta gain of Q1 is 100 then the available collector current will be close to 100mA. When RB5 goes high, Q1 turns on and so LED1 and the transducer also turn on. A 330W resistor limits the current through the LED to about 10mA, while a 15W resistor limits the volume from the piezo transducer. Reset line & power Table 2: Capacitor Codes The MCLR pin of IC1 is pulled to the +5V supply rail by a 2.2kW resistor. This ensures that the microcontroller is reset when power is first applied. The +5V supply itself is derived from a +5V rail on the keysocket con- Value μF Code EIA Code IEC Code 100nF 0.1µF   104 100nF 22pF   NA    22   22p Table 1: Resistor Colour Codes o o o o o o siliconchip.com.au No.   4   1   2   1   1 Value 100kW 4.7kW 2.2kW 330W 15W 4-Band Code (1%) brown black yellow brown yellow violet red brown red red red brown orange orange brown brown brown green black brown 5-Band Code (1%) brown black black orange brown yellow violet black brown brown red red black brown brown orange orange black black brown brown green black gold brown March 2006  35 Par t s Lis t Keypad Advantages & Disadvantages 1 PC board, code 07203061, 104 x 38mm 1 IP65 ABS case, 115 x 65 x 40mm (Jaycar Cat. HB-6122) 1 front panel label (download from www.siliconchip.com.au) 1 4MHz crystal (X1) 1 3 x 4 matrix numerical keypad 1 piezo transducer (Jaycar Cat. AB-3440) 1 D9 male connector 2 D9 female connectors 2 D9 backshells 6 M3 x 10mm screws & nuts 4 M3 x 5mm screws 1 18-pin IC socket (for IC1) 1 150mm length rainbow cable 1 1-metre length 4-core cable 2 small cable ties, 100mm 1 4-way SIL locking pin header & connector, 2.54mm (CON1) 1 2-way SIL locking pin header & connector, 2.54mm (CON2) 1 10-way SIL locking pin header & connector, 2.54mm (CON3) The keypad module was developed mainly to make it easier to disarm the alarm system in the event of a mains or PC failure, as opposed to using the hard-wired key. Unlike the hard-wired key though, it can also be used to arm the system. That means that you can do away with the PC and just rely on the keypad if that’s more convenient. There are some drawbacks to relying solely on the keypad, though. Basically, you lose the nifty access control features that the PC software has to offer. Four codes can be defined for the keypad but they all provide full control over the system – the keypad either turns the whole system (ie, all zones) on or off. Note that the independent zone entry/exit delays and the siren duration time are stored in the main system, so you don’t lose these settings if you decide to rely on the use of the keypad after the initial set-up. There’s just one thing to watch out for here – if you disarm the system using a PC and then rearm it using the keypad, the auto rearm options will kick in (assuming they’re set). This is because the PC sends a command to the alarm for auto-rearming when you click on the disarm button. This command also includes the time duration before auto-rearm is applied (although this obviously only occurs if it’s enabled). This is something to watch out for if you decide to use both the keypad and the PC. Semiconductors 1 PIC16F84A microcontroller pro­grammed with keypad.hex (IC1) 1 BC548 NPN transistors (Q1) 1 5mm red LED (LED1) Capacitors 1 10mF 16V electrolytic 1 100nF MKT polyester (code 104) 2 22pF ceramic Resistors (0.25W, 1%) 4 100kW 1 330W 1 4.7kW 1 15W 2 2.2kW Where to buy parts PC boards for this project are available from RCS Radio, phone (02) 9738 0330. In addition, RCS Radio offers a programming service for the PIC chips used in both the keypad and the main alarm unit. EXT Siren + - INT Siren + - Door S A + - Door S B + - 22pF capacitors provide the correct loading on the crystal, to ensure reliable starting. Construction All the parts except for the D9 connector, transducer and LED are installed on a PC board coded 07203061. It measures just 104 x 38mm and fits into a standard IP65 plastic case from Jaycar. Fig.9 shows the parts layout on the PC board. It should only take you 10 minutes to assemble and you can install the parts in any order. Use a socket for microcontroller IC1 and take care to ensure that this IC and transistor Q1 are both oriented correctly. Similarly, make sure that the 10mF capacitor is installed correctly. Table 1 shows the resistor colour codes but it’s also a good idea to check them using a digital multimeter. Don’t forget the wire link that’s adjacent to the 4MHz crystal (X1). The Tamper Switch 1 Com N/C GND RX TX Alarm OUT < ZONE INPUT > 2 3 4 5 6 7 +12V 8 ~ ~ AC IN Alarm OUT Fig.10: these labels can be cutout and affixed to the main board in the alarm system – ie, adjacent to the external wiring connectors. 36  Silicon Chip crystal can go in either way around. Once the board assembly is complete, mount the keypad on the lid of the case – use the front panel label as a template to mark the cutout and the four mounting holes. The cutout can then be made by drilling a series of holes around the inside perimeter, knocking out the centre piece and filing the job to a smooth finish. That done, the kepad can be fastened to the lid using four M3 x 10mm screws and nuts. The PC board can then be mounted in position. It’s secured to the integral pillars in the case using for M3 x 5mm screws – see photo. Finally, complete the construction by wiring the D9 connector, piezo transducer, LED1 and the keypad to their respective connectors and plugging them into the on-board headers. Testing Before testing, you need to open up the main alarm unit and connect a link between pin 1 of the D9 connector and one of the +5V pins on the key socket connector. This is necessary so that a +5V rail is applied to pin 1 of the D9 connector on the keypad module. After that, it’s simply a matter of connecting the keypad module to the alarm unit, setting up the password(s) in the software (via the configuration GUI) and trying it out. That’s it – your new alarm system SC is ready for action. siliconchip.com.au PC Oscilloscopes & Analyzers Get the full picture with BitScope Mixed Signal Oscilloscopes 100MHz Digital Oscilloscope  Dual Channel Digital Scope using industry standard BNC probes or analog inputs on the POD. 40MS/s Logic Analyzer  8 logic, External Trigger and special purpose inputs to capture digital signals down to 25nS. Mixed Signal Oscilloscope  True MSO to capture analog waveforms time-aligned with logic using sophisticated cross-triggering on any input. Turn your PC into a powerful Digital Storage Oscilloscope! Real-Time Spectrum Analyzer  See spectra and waveforms in real-time displayed simultaneously See inside your circuit with simultaneous analog, logic and spectrum displays to make tracking down those elusive real-time bugs much easier. Waveform Generator  Load up to 128K arbitrary waveform and replay via BNC B. Capture circuit response simultaneously on BNC A Standard 1M/20pF BNC Inputs 200uV-20V/div with x10 probe S/W select AC/DC coupling Switchable 50ohm termination Arbitrary Waveform Generator BitScope combines a high speed synchronized storage scope and logic analyzer with a programmable waveform generator and spectrum analyzer. With "Smart POD" connected active probes and multiple software options you've got the perfect low cost high performance test and debug solution! BitScope Smart POD probe connector 8 logic channels, cross-triggering Dual channel analog inputs Async serial I/O for external control Supports active probes USB 2.0 or Ethernet Connectivity Single cable to PC or switch Compressed data transmission Ethernet option uses UDP/IP Internet addressable device Expandable and Programmable Simple ASCII Protocol BitScope Scripting Language Add active probes and devices Supplies up to 500mA via POD BitScope DSO software for Windows and Linux BitScope's integrated design uses standard oscilloscope probes and a growing range of custom probes to provide functionality equal to instruments many times the price. BitScope plugs into third party software tools and has an open API for user programming and custom data acquisition. BitScope Designs siliconchip.com.au Ph: (02) 9436 2955 Fax: (02) 9436 3764 www.bitscope.com March 2006  37 The tiny droplet size resulting from the use of the “espresso” pump and a Spraying Systems nozzle can be seen here. In this case, the nozzle is aimed forwards and the car drives into the cloud of water droplets. These very effectively cool a front-mounted intercooler and as a bonus also help cool the other radiators! By JULIAN EDGAR Low-Cost Intercooler Water Spray Controller A cheap but sophisticated way of controlling a turbo car intercooler water spray M OST TURBOCHARGED petrol and diesel car engines use intercoolers – radiators that cool the air after it has been compressed by the turbo. An intercooler has twin benefits of providing more power (the intake charge is cooler and therefore denser) and in the case of petrol engines, reducing the chance of detonation. In many cases though, the intercooler is too small for best performance – especially in a hot country like Australia. This can be greatly improved by adding a water spray – the small droplets evaporate on the core, lowering its temperature. How do you trigger the spray? Many people use a boost pressure switch – but this wastes lots of water because the spray operates even when the 38  Silicon Chip intercooler is cool. Another approach is to use a temperature switch but this also wastes a huge amount of water because it doesn’t take into account heat-soak (eg, when the car is stopped for a long time in traffic), where a simple temperature switch can continue to run the spray until the tank is emptied. Also, both types of switch cannot easily be adjusted for their switch-on points. Possibly the best way to trigger the water spray is on the basis of measured intercooler temperature and engine load; when both are high, the spray is switched on. This wastes very little water because the spray operates only when it is really needed. So now we know what we want – but how to get it? The answer is that the Smart Mixture Meter project (described in both the “High Performance Electronics for Cars” book and in the April 2005 issue of SILICON CHIP) provides nearly all that we need. In fact, it provides even more features, with a colour LED bargraph that can be used to show intercooler temperature! To transform it into its new function we need add only a handful of components and make some simple changes to the PC board, none of which require cutting tracks. That makes it one very cheap and easy to build Intercooler Water Spray Controller! Smart Mixture Meter The Smart Mixture Meter was designed to monitor the output of the siliconchip.com.au Fig.1: the circuit is virtually identical to the Smart Mixture Meter, described in Performance Electronics For Cars. An LM3914 IC drives the display LEDs, while op amp IC2b, transistor Q2 and Relay 1 control the water spray. oxygen sensor which indicates the rich/lean status of the air/fuel ratio. Two inputs were provided – one from the oxygen sensor (with its output shown on a LED bargraph) and the other from a load sensor, such as the airflow meter. When the load was above a set threshold and the output of the oxygen sensor showed that the fuel mixtures was lean, a piezo alarm sounded, to give a “lean-out” warning. We have adapted the Smart Mixture Meter to control a water spray controlsiliconchip.com.au ler. It needs a load input with an adjustable switching threshold, while the oxygen sensor input is connected to a thermistor, with its output configured to drop with increasing temperature. Therefore, with very little change to the existing kit, the piezo alarm will sound when the intercooler temperature and engine load are both high. But instead of operating a piezo buzzer, the circuit now operates heavy-duty automotive relay, to switch a spray pump. Finally, so that the intercooler water New Par t s Required 1 BD682 PNP Darlington transistor (Q2) 1 1N4004 silicon diode D4 1 single pole single throw (SPST) 30A automotive relay (Jaycar Cat. SY-4068 or equivalent) 1 2200mF 16V electrolytic capacitor 1 4.7kW 0.25W resistor 11.8kW 0.25W resistor 1 4.7kW thermistor (Jaycar RN3438) March 2006  39 Fig.2: this is the modified PC board layout for the Intercooler Water Spray Controller. Alternatively, you can build the Smart Mixture Meter exactly as detailed in the kit instructions, verify that it is all working correctly and then modify it by following the step-by-step instructions in the article. Don’t forget the 4.7kW resistor that’s fitted on the copper side of the board (shown in red) – it should be insulated from the tracks using heatshrink sleeving – see text. spray won’t turn off on gear-changes or when the load is fluctuating rapidly, we add a 1-second switch-on delay and a 2-second switch-off delay. Changing The Mixture Meter The Intercooler Water Spray Controller can be built in two ways. The first way – best if you’re a kit beginner – is to build the Smart Mixture Meter exactly as per the original kit instructions. That way, you can test the final result and be sure that the device is working before undertaking the modifications that turn it into the Intercooler Water Spray Controller. The other way is to build the kit from scratch as the Intercooler Water Spray Controller, incorporating the modifications as you proceed. Here are the modifications: THERMISTOR INPUT: as indicated earlier, a thermistor is used to sense intercooler core temperature – the resistance of the thermistor decreases with increasing temperature. So that the voltage signal received from the thermistor never drops to near zero (which would cause all the bargraph LEDs to be off), a 1.8kW resistor is wired in series with it. It’s easiest to solder the resistor in-line with the cable going to the thermistor and then cover the lot with heatshrink sleeving. The thermistor/resistor assembly is then wired between the original Oxygen Sensor input (now the Thermistor Input!) and the ground connection. In order that it acts as a voltage divider, power needs to be supplied to the thermistor. This is achieved by wiring a 4.7kW resistor between pin 7 of IC1 and the thermistor input. The new resistor and its connecting wiring are most easily soldered into place under the PC board, with the additions insulated with heatshrink sleeving. As with all the PC board changes, Fig.2 shows where this resistor goes. If you have built the Smart Mixture Meter and want to test the modifications as you go along, you can now power up the board and check that when you heat the thermistor, the illuminated LED moves along the scale. DARLINGTON TRANSISTOR: Q2, the BC327 transistor, is not up to the task of supplying enough power to run a heavyduty relay and so needs to be replaced. Why Measure Intercooler Temperature? At first glance it would seem that rather than measuring intercooler core temperature, it would be better to monitor actual intake air temperature. However, this is not so. Intake air temperature can rise substantially when the vehicle is stopped, for example, at traffic lights. However, if the stop is a short one, the intercooler will remain relatively cool. If intake air temperature was being monitored to trigger the spray, the spray would come on when the car was driven off under high load. But the intercooler would in fact still be cool – so water would have been wasted. 40  Silicon Chip A simple pump/reservoir combination for an intercooler water spray can be cheaply obtained by using a late model Holden Commodore windscreen washer reservoir and pump. siliconchip.com.au The Intercooler Water Spray Controller is based on the Smart Mixture Meter, previously published in SILICON CHIP. Seven new components are needed and the modifications are straightforward. The Water Spray Controller operates an intercooler spray whenever engine load and intercooler temperature are both above preset levels. The replacement is a BD682 Darlington transistor. Note that the pin-outs of this transistor are not the same as the original BC327, so care should be taken in following the overlay diagram (Fig.2) and the photographs when installing this device. At this stage, remove the 680W resistor that is positioned on the PC board directly above diode ZD4. Now, with the new transistor in place the board should work as it did previously. That is, by appropriately setting trimpots VR4 and VR5, LEDs 11 and 12 should be able to be switched on and when they are both illuminated, the piezo buzzer should sound. DIODE AND RELAY: the relay and the transistor protection diode replace the piezo buzzer. The 1N4004 diode is placed so that its cathode (the white band) is towards the top of the PC board. Again, check the overlay diagram and photos. When you have inserted and soldered this diode in place, don’t cut the leads off short. Instead, leave enough of each lead protruding through the siliconchip.com.au ABOVE: two changes are made on the back of the PC board: (1) a 4.7kW resistor is used to link pin 7 of IC1 with the thermistor input (here the resistor is covered in heatshrink); and (2) two flying leads are added, one to each side of the diode that’s installed in place of the piezo buzzer. These flying leads connect to the relay coil. RIGHT: transistor Q2 is now a BD682. Its pinouts are not the same as the original BC327: the new transistor must be installed as shown here. March 2006  41 show that when LEDs 11 & 12 are on, there is a short delay before the relay pulls in. Also, when one or both LEDs switch off, there should be a longer delay before the relay drops out. If you want to increase the length of these delays, increase the value of the capacitor – say by adding another 2200mF 16V capacitor in parallel. If you want to decrease the length of the delays, reduce the value of the capacitor. Note that because this capacitor provides an anti-chatter function, the lowest value that should be used is 1000mF. OPTIONS: if you wish to, you can alter The nozzle (circled) sprays a fine mist of water over the intercooler to improve performance. A spray is especially beneficial when the intercooler is mounted under the bonnet. board to allow flying leads to be easily soldered to them. Connect these flying leads to the relay’s coil contacts. We suggest you use a heavy-duty automotive type relay, in which case these leads will connect to terminals 85 and 86 on the relay. If you’re checking things as you go along, power up the board and confirm that the relay pulls in with an audible click whenever LEDs 11 and 12 are both illuminated. DELAY: the switch-on and switch-off de- lays are provided by a 2200mF capacitor wired in where the 680W resistor previously resided. This won’t fit on the board so should be wired in place with flying leads and then glued to the inside of the box or placed horizontally over the new diode. When viewed as shown in the overlay and photos, the capacitor should be wired with its negative lead to the right. Testing of the finished design should Quick Guide To The LEDs & Trimpots The kit instructions for the Smart Mixture Meter explain how the circuit works and lists in more detail the function of each LED and pot. But here’s a quick reference guide for when the circuit is being used as an Intercooler Water Spray Controller: • LEDs1-10: show temperature based on thermistor input, LED1 (red) indicating hottest and LED10 (yellow) indicating coldest • LED11: “on” indicates the trip point for temperature has been reached • LED12 “on” indicates the trip point for load has been reached • VR1 sets the cold end of the scale • VR2 sets the hot end of the scale • VR3 sets the night dimmer sensitivity • VR4 sets the temperature trip point • VR5 sets the load trip point 42  Silicon Chip the position of the LEDs to better indicate the rise in intercooler temperature. For example, you can swap the position of the green and yellow LEDs so that as temperature rises, the illuminated LED alters from green through to yellow and then red. Or you can replace some of the green LEDs with yellow LEDs, etc. Bench Calibration Now for the calibration. First, set both trimpots VR1 and VR2 to their centre positions. That done, ensure that the thermistor is at room temp­ erature (~20°C), then rotate VR1 until LED9 (yellow) lights. When it does, adjust VR1 a little further anticlockwise until LED10 is just lit. Warming the thermistor with your hand should then move the illuminated LED from LED10 to LED9. Now use a heat-gun to further warm the thermistor. When it is just too hot to touch (eg, 55°C), rotate VR2 clockwise until LED1 (the “hottest” LED) lights. Make sure you don’t turn it so far the LED goes out. When the thermistor is again cold, you may need to tweak VR1, as the pots interact with each other to some extent. When calibrated in this manner, the bargraph display is then configured to show intercooler temperatures over approximately a 20-55°C range. Note that because of the thermistor’s characteristics, the bargraph isn’t linear – it needs a bigger change in temperature to move a LED at the hot end than it does at the cold end. Installation For remote installation, the thermistor should be soldered to some twincore flex and the joins insulated with siliconchip.com.au This Ulka solenoid pump is capable of extremely high pressure, resulting in a very finely atomised intercooler spray. The pump is normally used in espresso coffee machines and requires a small 12V DC to 240VAC inverter to run in car applications. heatshrink sleeving. The thermistor should then be pushed well into the fins of the intercooler, inserting it from the rear of the core. This location will give the best indication of intercooler temperature. The thermistor may need to be held in place with a dob of silicone adhesive. The load input for the Intercooler Water Spray Controller can be taken from the airflow meter or MAP sensor outputs – or where these are not available, from the throttle position sensor. This can be done at the ECU or the sensor itself. Use the workshop manual wiring diagram to find the load sensor output and then use your multimeter to check that it’s correct. The measured voltage on the load sensor output should rise with engine load. Note, however, that some cars use a frequency output on the airflow meter. In that case, use the throttle position sensor output. The intercooler water spray pump relay is best located under the bonnet, close to the pump. Test that when trimpots VR4 and VR5 are adjusted so that their adjacent LEDs are on, the pump turns on and the water spray operates. Driving Tests With an assistant in the car, drive the car and monitor the displayed temperature on the bargraph. The lit LED should move up and down the display with the variation in intercooler temperature. Adjust VR4 until its adjoining LED lights when the intercooler is becoming warm. Then adjust VR5 siliconchip.com.au This Spraying Systems brass nozzle incorporates a filter and non-drip check-valve. This nozzle gives far better results than the small garden irrigation nozzles that are widely used in intercooler spray applications. Spraying Systems can be contacted in Australia on (03) 9318 0511. until its adjoining LED lights when the car is coming onto boost. Drive the car so that the intercooler gets warm and the car is under load and check that both LED11 (intercooler temperature) and LED12 (load) light. When both have been lit for more than about a second, the water spray will operate. (If you want an on-dash indication that the water spray pump is running, wire a 12V pilot light in parallel with the pump.) After monitoring the displayed inter­ cooler temperature, you may decide that you want to make further adjustments to the load or temperature trip points. Another important aspect to keep in mind when setting these thresholds is water consumption – check this over a few weeks to make sure that you haven’t got the system tripping too early. The Intercooler Water Spray Controller can be mounted so that the bargraph LEDs can be seen by the driver or alternatively, the whole device can be located out of sight. Conclusion Intercooler water sprays are a very effective and cheap way of upgrading intercooler performance. However, using a “dumb” system to trigger the spray often results in the need for frequent water top-ups. Compared with such an approach, the Intercooler Water Spray Controller is likely to reduce water consumption by up to two-thirds with no loss in SC cooling efficiency. Water Spray Pumps And Nozzles The cheapest and simplest pump and nozzle combination is to use a windscreen washer pump and reservoir and a miniature garden irrigation spray nozzle. Late model Holden Commodores use good quality pumps and large, box-shaped reservoirs. A dramatic improvement in spray quality can be gained by using brass nozzle assemblies from US company, Spraying Systems. These incorporate a mesh filter and check valve and provide much smaller droplet size than can be achieved with the garden nozzle. Spraying Systems can be contacted in Australia on (03) 9318 0511. These nozzles can be used with windscreen washer pumps. However, if you want an intercooler spray of almost unbelievable efficiency, use the Spraying Systems nozzle with an Ulka solenoid pump, as used in cappuccino coffee machines. These 240VAC pumps develop extremely high pressures, are designed to flow water, are light and small, and are quiet-running. In car applications, a small 12V DC to 240VAC inverter can be used to power them. Jumbo Coffee (02 9666 6114) sell these pumps. March 2006  43 The expansion boards connect to the AVR200 via its I2C bus connector. Most expansion boards have two bus connectors, allowing them to be daisy chained. The AVR212 and AVR213 boards shown here provide eight additional outputs and inputs, respectively. Six low-cost E x pan sion Board s for the AVR200 Add up to 128 bits of digital I/O, a keypad and LCD, more non-volatile memory – or a combination of any of these for a very reasonable price. By PETER SMITH B ACK IN JUNE AND JULY 2005, we described a low-cost, highperformance development board from JED Microprocessors based on the popular ATmega32 microcontroller. Since then, JED have produced a complete range of add-on modules for the AVR200, most of which can be purchased in kit form. Included in the range are prototype, I/O expansion, non-volatile memory, keypad and LCD interface boards. All boards communicate via the I2C (TWI) serial bus, with the prototype and memory boards plugging directly into the AVR200’s “upstairs” connector (J14). All other boards connect via the AVR200’s 10-way I2C header (J6) and use the Philips 82B715 bus extender IC for communication at up to 100m (at 44  Silicon Chip the 71kHz data rate) from the AVR200 using ordinary ribbon cable. Note that as the I2C bus frequency is reduced this distance will increase; refer to the Philips application note AN10216 (available from www.semiconductors. philips.com) for specific details. All remote boards are based around the PCF8574 or PCF8574A 8-bit I/O expander IC. Essentially, these ICs act as addressable nodes with eight input/ output lines. Most boards include two I2C headers, allowing subsequent boards to be wired together in daisychain fashion. This makes for a truly simple and flexible expansion system. Let’s look at each board in a little more detail. AVR201 I2C FRAM board Up to eight FM24C256 chips can be installed on the AVR201 for a total of 256Kbytes of non-volatile memory. Alternatively, the board can be ordered with one, two or four chips for a total of 32, 64 or 128Kbytes of memory, respectively. The FM24C256 is a ferroelectric random access memory (FRAM) device with a read/write endurance of at least 10 billion cycles, no write delays and data retention for at least 10 years. Individual memory chips can be hardware write-protected by installing jumpers on the board. Input power requirements are 5V DC at 800mA (idle), increasing to about 1.2mA during read/write access. As mentioned earlier, the AVR201 plugs directly into the “upstairs” connector (J14) on the AVR200, as does the AVR202 prototyping board, so these siliconchip.com.au Silicon Chip Binders REAL VALUE AT $12.95 PLUS P & P These binders will protect your copies of S ILICON CHIP. They feature heavy-board covers & are made from a dis­ tinctive 2-tone green vinyl. They hold 12 issues & will look great on your bookshelf. The AVR202 prototype board makes it easy to assemble and test experimental circuits. It mounts directly above the AVR200 board. two don’t readily co-exist. Note that as the FM24C256 memory chips are only available in surfacemount packages, JED has elected to offer the AVR201 in preassembled form only. This eliminates the hassle of soldering these subminiature devices by hand. AVR202 prototype board Experimental circuits can be conveniently built and connected to the AVR200 using the prototyping board. This board plugs into “upstairs” connectors J13 & J14, which provide access to both the I2C and SPI buses, as well as several bits of Port B. The board mounts in satellite fashion directly above the AVR200 and is secured to it by four tapped spacers and screws. Included on the board is space for six decoupling capacitors, four LEDs and their current-limiting resistors, and four 5-way screw-terminal blocks. The remainder of the board is laid out with a large array of platedthrough holes on a 0.1-inch grid, just waiting for your next invention! In addition, it supports the latest PLED (polymer-based LED) displays that are compatible with the older LCD technology. Compared to backlit LCD modules, these have the advantages of lower power consumption and brighter displays with wider viewing angles. Various linking options and resistor values allow for minor variances between the two display types and backlighting options. For example, the on-board potentiometer can be set to control either LCD contrast or PLED brilliance. siliconchip.com.au H SILICON CHIP logo printed in gold-coloured lettering on spine & cover H Buy five and get them postage free! Price: $A12.95 plus $A7 p&p per order. Available only in Aust. Silicon Chip Publications PO Box 139 Collaroy Beach 2097 Or fax (02) 9979 6503; or ring (02) 9979 5644 & quote your credit card number. Use this handy form Enclosed is my cheque/money order for $________ or please debit my  Bankcard  Visa    Mastercard Card No: _________________________________ Card Expiry Date ____/____ AVR210 I2C LCD board Adding a liquid crystal display to the AVR200 becomes a relatively simple task with the aid of an AVR210. This board works with any alphanumeric LCD that uses an integrated HD44780 or compatible controller. H 80mm internal width Signature ________________________ The KEY200A 16-key stick-down keypad features “user-loadable lettering”. Name ____________________________ Address__________________________ __________________ P/code_______ March 2006  45 Both single and dual-row header display types can be accommodated, due in part to the small size of the AVR210 as well as its mounting method. Basically, it’s attached to the rear of the chosen display module via the header and several layers of double-sided tape. Backlighting is software controllable and can be powered either by the I2C bus or a separate DC power source, depending on current requirements. For an AVR210 equipped with an LCD (no backlighting), the board draws about 20mA at 5V. However, for a large 4 x 20 LCD with LED backlighting, this requirement could increase to over 180mA. Interestingly, this board and the AVR211 keypad interface can be built as buffered or non-buffered I2C peripherals. For the non-buffered builds, the main omission is the 82B715 bus extender chip, presumably to cut costs in short distance I2C bus hook-up schemes. AVR211 I2C keypad board The AVR210 easily attaches directly to the rear of most alphanumeric LCD or PLED modules. Most modules can be powered from the I2C bus or an external supply can be connected for units with high-current LED backlights. Need a keypad to complete your front-panel interface? JED has this angle covered too with their AVR211 keypad interface board. This board allows the AVR200 to read up to 16 individual push-button switches wired in a 4 x 4 matrix. Continual switch polling is unnecessary, as the PCF8574’s interrupt pin can be programmed to signal when a switch closure takes place. If you need a keypad rather than individual switches, then JED offers the KEY200A 16-key stick-down keypad with “user-loadable lettering”. A keypad can be customised and mounted ready for use in just a few minutes with this system. As with all other boards, the AVR­-211 receives its regulated 5V supply from the AVR200 via the I2C bus cable. Typical supply current is a respectable 20mA. AVR212 I2C output board This “Floribots” interactive kinetic sculpture is powered by a single-board computer with similar capabilities to the AVR200. It was created by Geoffrey Drake-Brockman and was short-listed for the 2005 National Sculpture prize. Specifically, Floribots incorporates a JED573 microcontroller board, which is similar to the AVR200 but incorporates an ATmega128 micro. Sixteen AVR212 output boards drive the sculpture. The whole shebang runs a compiled BASIC program and monitors the outside world via eight infrared sensors. More details can be found on the JED website at www.jedmicro.com.au/avr200.htm. 46  Silicon Chip This board allows you to add eight more digital outputs to the AVR200. It features high-current open-drain Mosfet outputs, with the state of each output displayed by a rectangular green LED. Although the supplied Mosfets are capable of sinking greater than 10A continuous current, the maximum safe current level is determined by the siliconchip.com.au The guys at JED recently needed a jig for testing wiring harnesses, and their solution was (not surprisingly) an AVR200 with lots of extra I/O. As shown here, the end result was stuffed with four AVR212 output boards, eight AVR213 input boards and the whole lot mounted on a wooden backing board! The test software was written in BASIC for the BASCOM compiler. JED will supply the code to anyone interested in seeing how it was all done. AVR212’s PC board track width. In this case, ground current must be limited to 4A per group of four Mosfets or 1A per Mosfet. Like the AVR213 input board (see below), the AVR212 has eight possible address configurations, selectable with on-board jumpers. The on-board PCF8574 and PCF8574A I/O expander chips occupy two different address ranges, so up to 16 unique addresses are achievable by using both device variants. This means that up to 16 input/output boards can be installed on one I2C bus for 128 individual I/O lines. In standby mode with no LEDs illuminated, the AVR212 draws a maximum of 15mA at 5V. With all LEDs lit, this will increase to approximately 60mA. AVR213 I2C input board The AVR200’s digital input capability is readily expanded with the aid of an AVR213 input board. These boards have eight general-purpose inputs, all of which are over-voltage protected. Inputs can be pulled up to 5V or down to ground simply by repositioning two plug-in resistor packs. The state of all bits is made visible siliconchip.com.au via a row of rectangular red LEDs. In addition, the AVR213 can be programmed to generate an interrupt whenever an input changes state. Note, however, that only two interrupt lines are available on the AVR200’s I2C bus, which may limit this feature when using multiple boards. In some applications, it would be possible to share interrupt lines between boards, as the PCF8574’s interrupt output is open drain. In standby mode with no LEDs illuminated, the AVR213 draws a maximum of 15mA at 5V. With all LEDs lit, this will increase to approximately 60mA. Software Most of the I2C boards described here are supplied with demonstration programs written in C for the CodeVision AVR C compiler. These can be used to test the boards as well as gain an insight into how to access their various elements from within your own code. What’s coming? JED Microprocessors is currently working on more I2C expansion boards for the AVR200, including a multiple This is the AVR201 FRAM board with all eight FM24C256 chips installed for 256kbytes of non-volatile memory. The AVR211 keypad interface board allows the AVR200 to read up to 16 keys in a 4 x 4 matrix. servo actuator driver and an 8-bit power relay board. Need something special? The engineers at JED are always ready for a new challenge – give them a call! Pricing and technical details for the complete range of I2C expansion boards can be obtained from www. jedmicro.com.au/avr200.htm. You can reach JED Microprocessors on (03) 9762 3588 or via email at jed<at> SC jedmicro.com.au March 2006  47 SERVICEMAN'S LOG The beautiful-looking Philips TV set Salt air and electronic equipment don’t mix well and this month it caused problems in a really nice-looking Philips TV set. Then there was Mrs Struddle’s old Sansui amplifier to fix, Mr Bond’s Mitsubishi TV set, a couple of strange faults in audio gear and finally, an overheating Compaq laptop computer. I recently had a really beautiful looking Philips TV come into the workshop. This set was the 32PW9566/79 which uses an MG2.1E chassis. It is a very elegant set which comes integrated into a white, grey, silver and glass stand. Unfortunately for this set, it lived near the sea (actually almost right on it). And the fault was that it was completely stone dead, with not even the standby light coming on. Well, of course, that was the clue. After checking the main fuse, it was obvious that the +5V standby supply rail wasn’t working. A quick check revealed that 240V AC was going into the bridge rectifier and that 330V was coming out. This was then fed to a 10W resistor, before going to the chopper transformer (5101). However, there was no voltage on the switching FET. Removing the transformer from the Items Covered This Month • Philips 32PW9566/79 TV set (MG2.1E chassis) • Sansui AU217 Mk.2 audio amplifier • Mitsubishi CT33AC2S (A) TV set (AC2 or A1X chassis) • Sony CDXM630 car stereo head unit • Sony F240 audio amplifier • Compaq Presario 1200 48  Silicon Chip circuit board revealed the trouble. On one of the legs, the winding had a green spot on it where the copper had corroded. I soldered a link across the break, replaced the transformer and the set came on. However, that wasn’t the end of it, as the line output transformer was arcing, which meant that it had to be changed. The rest of the set was pretty corroded too. Not only that, but the Defect Errors in the service menu showed 068, 067 and 073 which point to faults in the deflection circuits. Replacing these will give the set a little more life. Mrs Struddle’s Sansui Mrs Struddle had owned her 1980 Sansui AU217 MkII amplifier since new and was very fond of it. Unfortunately, it had had the temerity to die on her and she entrusted it to our Dave to do his Lazarus thingy – on the amplifier, that is. It didn’t take too long for Dave to realise that the output transistors (2SD188A & 2SA545A) had blown, taking the fuses with them. But what was causing the problem? Using a Variac and a series globe as a visual current limiter, he gingerly wound it up. All he could hear was a slight crackling noise that increased when the differential amplifier (2SA798) was touched with a cotton bud soaked in freezer. Replacing it fixed the problem and the amplifier now seemed to be working OK. But not for long – he was performing the final checks before putting it on soak test when he noticed that there was no bias adjustment control and annoyingly, the crackle had come back to haunt him. Luckily, he spotted the snotty brown glue that has caused so much grief for electronics through the 1980s and 1990s. When he removed it, he found that series diode D507’s anode was corroded right through. Replacing this diode allowed him to realign the bias for 2mV before he thoroughly tested it with a hairdryer and freezer and then left it on for a prolonged soak test. It all passed with flying colours and Mrs Struddle was ecstatic. Not quite 007 Mr Bond has a beautiful house with a lovely view on top of a hill. He also has a 33-inch Mitsubishi DIVA TV which he thought was only four years old – and it had a white line across the screen. I was a bit perplexed about this, as I thought Mitsubishi had ceased TV production in the latter part of the 90s. In the event, it turned out that his set was a 1995/6 CT33AC2S (A) using an AC2 or A1X chassis (I can’t work out how their chassis numbering system works). Even though I have worked on quite a number of these sets, I was apprehensive about repairing this because of the logistics involved in manoeuvring a large heavy TV up a large number of steps. However, I felt sure the fault would be only dry joints. So off I hiked, ready to do the business on top of the summit! The day was hot and humid and by the time I got there I was pretty sweaty. Mr Bond sat and watched as I worked. The set was in a corner on a fixed stand. This model has a remote-controlled swivel base, which meant that I could move it almost completely around to get to the back. siliconchip.com.au There is no real service position for the large flat chassis and you have to remove the two screws inside the front AV panel on the righthand side, plus negotiate with two concealed black plastic clips on either side, to be able to remove it – plus, of course, unplug a lot of the wiring harness. Eventually, with the sweat pouring off me, I managed to get access to the PC board. I carefully discharged C915 and C916 siliconchip.com.au and then found dry joints on T451, IC451 and IC452. So far, so good. Despite Mr Bond’s eagle eye, the repair had gone reasonably to plan. All I had to do now was refit the chassis and switch on. However, when I did this, nothing happened. Only the red standby LED was on. Trying not to panic, I retraced my steps to find out what I had done. Well, I looked and looked and couldn’t see that I had done anything wrong at all. And I had left my meter in my car at the bottom of the hill. Helpful questions This had all taken quite a bit of time and Mr Bond was beginning to ask helpful questions, such as “Do these normally take this long to fix?”. Unfortunately, I had no idea what March 2006  49 Serviceman’s Log – continued had gone wrong and I was too hot and bothered to continue the repair there in the home, especially as I was now running late for my next appointment. In the end, I “fessed up” and said I would have to take the chassis to the workshop. Mr Bond reluctantly agreed to let me but made clear his concerns as to what the job might cost. I reassured him that everything would be OK and that I would return the next afternoon. The next morning, feeling much more refreshed, I examined the chassis carefully after blowing off all the dust. I then touched up a few potential dry joints but found nothing that was definitive. Next, I shorted the base and emitter terminals of the line output transistor and hung a DVM off the collector, along with a 100W globe. When the set was switched on, the globe glowed, the B+ was spot on and the remote easily switched the set on and off, the red and green LEDS coming on alternately. In short, everything looked ship-shape! I changed C921 (2.2mF 63V) and C923 (47mF 63V) in the switchmode power supply just in case, before phoning Mr Bond with a firm final quote on the repair. He had no problem with my figure and so we arranged to recommence the repair at his home that afternoon. In due course, I was back at the coal face, feeling fairly confident that I was 50  Silicon Chip going to be out of there in about 10 minutes. Mr Bond once again took a ringside seat, like Madame Defarge at the guillotine. Anyway, I reassembled the set and switched on. And nothing happened again! Mon Dieux! – how could this be? I had my meter with me this time but could only do a few measurements as access from the top was so poor. The red standby LED was on but the set would not switch on to green no matter what I did. Despite my considerable frustration, I was determined not to be beaten – damn it all, it was only a TV set! Logically, the chassis had been working only a few hours earlier so what had I done to it subsequently? Obviously, I had replugged the ancillaries into the chassis – perhaps something there was significant. The only thing to do was unplug each item in turn until the set came on. I began by unplugging the degaussing coils, speakers and deflection yoke but these made no difference. Similarly, unplugging the power supply to the swivel base motor had no effect and I was beginning to fear an humiliating retreat when I unplugged JB, a small 2-pin connector. Suddenly the set started to work, much to my relief – and also to the relief of Mr Eagle-eyed Bond. I wasn’t a complete and utter dork – only a fledgling. Well, I didn’t know what JB does. The two wires just disappeared into the lower dark morass of the cabinet but I suspected it had something to do with the swivel base, on which I had already noticed a front switch that was “jammed in”. I figured that what ever it was wasn’t important and that Mr Bond could live without it, so I reassembled the set without JB being plugged in. With the back on (and that gave a further bit of grief) and the set back in place, everything was looking good and working well. I told Mr Bond there was something wrong with the swivel base but he wasn’t concerned as he never used that feature. He thanked me and paid me courteously and left me to trek back to base camp. Later that evening, over a couple of “sherbets” to relieve my troubled brow, I examined the circuit and tried to speculate what was going on. Well, it turns out that JB goes to what can only be called a swivel base cut-out switch and if you look on page 69 of the instruction book, it says that if the set is swivelled more than a certain amount the set will not start. So in fact muggins me was the cause of this secondary problem because I had rotated the set almost 180° and activated the switch. If I had just turned it back, all would have been OK. I don’t quite know what the purpose of this switch is but can only assume it is some sort of safety circuit to protect the rotation motor. Of course, I expect there are quite a few ex-Mitsubishi technicians who are well aware of this but I had no idea and I don’t normally read 69 pages of instructions first before starting a repair – life is just too short. Car stereo We had an unusual problem crop up with a car stereo. It was a Sony CDXM630 head unit that came in with an intermittent skipping problem, especially on the outer tracks of the CD. Initially, the laser assembly was replaced but this made no difference and so a servo control IC was back ordered. Subsequently, it was noticed that when playing a CD, the CD was in fact wobbling all over the place, which made the original diagnosis suspect. We now suspected that it might be the spindle motor assembly. However, on even closer examination, it was siliconchip.com.au Yet another really obscure fault was in a very old Sony F240 amplifier with a blown channel. An IC had failed inside the set but this was now no longer available. And that generally means curtains for this type of unit. However, in this case, the ever obliging Sony Technical Officer moved heaven and earth before finding one in Taree. What’s more, we were able to purchase this IC at the price it was sold for all those years ago! Anyway, that fixed the F240 but didn’t explain why the fault occurred in the first place. It wasn’t until it was connected to the Richter loudspeakers that the cause was found. One speaker sounded awful and when the voice coil impedance was measured, it was found to be only 2W instead of the specified 8W. It also varied as the cone was moved. It wasn’t hard to discover the reason for this. As the cone moved, it was rubbing against the side and polling, causing it to have intermittent shorted turns. But you will never guess why it was poling – it was because bits of dog biscuit had got in through the air-vent damper and jammed in the voice coil! A new speaker fixed the problem and the cabinet was emptied of the rest of the dog biscuit! Finally, here is a contributed story from K. W. of Riverstone, NSW. I’ll let him tell it in his own words. The overheating Compaq www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com Another obscure fault ! W E ELEXOL Ether I/O 24 N www.elexol.com www.elexol.com www.elexol.com www.elexol.com UDP/IP-controlled digital input/output module featuring three 8-bit ports with 5V level signal lines. Each of the 24 lines can be independently programmed as either an input or an output. Connects to any TCP/IP protocol network. CT VIA CONNE TO TALK R ROUTE INTERNET TO ANYEVICE! D Supports ARP, BOOTP, DHCP, ICMP and UDP/IP protocols Standard 10BaseT Ethernet Interface; RJ45 connector 24 independently programmable signal lines with configurable CMOS, TTL or Schmitt Trigger thresholds and programmable pull-ups per line Easy connection by three 10-way box headers On-board 50MIPS flash micro-controller may be reprogrammed to suit specific applications Integrated switch-mode voltage regulator allows power supplies from 8-32VDC User 5V 500mA output to power external interface boards or sensors Compact module – 72 x 72 x 24mm Great range of I/O-24 peripherals, too ... CONNECTOR/ LED BOARD Provides screw terminal connections plus optional either pull up or pull down resistors and LED port status indication. OPTO INPUT BOARD Provides 8 Opto Isolated inputs for each of the I/O-24 pins with LED indication. RELAY OUTPUT SWITCH/PUSH BUTTON BOARD BOARD Provides 8 isolated relay contact outputs suitable for a variety of loads. Provides 8 switch/ push buttons with LED indicators showing the status of the I/O pin. Visit our web shop <at> www.elexol.com Elexol Pty Ltd Ph: (07) 5574 3988 Fax: (07) 5574 3833 (PO Box 5972, Bundall, Qld 4217) www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com www.elexol.com discovered that a sesame seed had glued itself on the platter, causing the wobble. Careful removal of the offending seed fixed the problem! Since the turn of the century, I’ve tended more and more to back away from computer repairs. In the “good old days”, things were different: you had a power supply, a motherboard and an assortment of expansion cards for the video, drive controllers and so on. Armed with a suitable assortment of replacement boards, memory SIMMs and a boot floppy, you could diagnose a lot of problems quite quickly. What’s more, PCs were worth fixing in those days. Unfortunately, nowadays most of these “peripherals” are part of the motherboard and although most CMOS setup screens allow you to disable these, that doesn’t help much if a faulty soldered-in chip is dragging down the data bus or similar. The incredibly low prices of new motherboards and PCs doesn’t help much either. I can still sort out older PCs but ironically, newer ones are rapidly becoming “disposable” items. As for laptops, in the normal scheme of things, I wouldn’t even consider touching one of those. They’re full of microscopic disk drives and flimsy flexible PC board connectors which “die” at a moment’s notice if touched! The most I’ll normally do is supply replacement batteries but most of these are horrifically expensive, even at trade prices. However, recently I had reason to question my personal “no way Ho-zay” policy – I actually fixed a laptop! The computer in question was a Compaq Presario 1200, about three years old, bought by a young relative who is always flitting from one get-rich-quick scheme to another. This time, he had visions of becoming a property magnate up in central Queensland and apparsiliconchip.com.au March 2006  51 Serviceman’s Log – continued ently a laptop is essential equipment for the young executive on the go up there! He paid almost $4000 for the thing, certainly no bargain even at the time, and now of course you can get better machines for under $800 when the sales are on! Unfortunately, it started to give trouble soon after he moved up there, which he put down to the climate – although being mainly designed for the US market, it should have been able to cope with 40°C temperatures without too much trouble. First, he reckoned it was the hard drive, then the motherboard, that needed replacing – but of course, he couldn’t fix it himself because “he didn’t have the right screwdrivers”. Yeah, right. Crash and burn In due course, this latest get-richscheme crashed and burned like all the others and he limped home with his tail between his legs and his boxes of personal effects somehow found their way into our garage! After considerable nagging on my part, he started to sort out his effects and one day I came home to find the laptop sitting in our rubbish bin with a lot of his other junk. After ratting around in his boxes of grubby clothes and other garbage, I 52  Silicon Chip located the mains power supply and the battery. Much to my astonishment, when I switched it on, the thing just worked! Windows fired up without a hitch and I had MS Word up and running and everything seemed fine. I ran it for a while to see if the battery was going to hold its charge but when I pulled the power plug, the computer instantly shut down, which meant the battery was cactus. But more seriously, the machine then refused all attempts at re-booting. It would get about halfway through the BIOS start-up screen then shut down with a loud “bonk!” I remember its owner mentioning that the only way he could get it to work for any length of time was to have a fan blowing in the back of it. I put it in the fridge overnight and sure enough, the next day I was able to get about 20 minutes out of it before it died. So it was a heat-related fault; maybe I could rig up some sort of workaround, or so I thought. My first problem was that the case is put together with some funnylooking star-headed screws, none of which matched any of my usual set of “weirdo” screwdrivers. But then I remembered a cheap “mobile phone service kit” I’d bought in a $2 shop. Would you believe it? – that had the right screwdriver! After that, it all came apart quite easily, although I wasn’t really sure what I was looking for. Desktop PCs are notorious for crook electrolytics overheating and leaking fluid on the motherboard but I couldn’t see any sign of that and my in-circuit capacitance meter didn’t find any signs of low capacitance anywhere. It was then that I spied something suspicious about the CPU heatsink. In the old days, when CPU chips cost several hundred dollars (and they hadn’t yet gotten into clock-speed turf wars), the silicon “dice” were normally bonded to a heat-conducting ceramic substrate and the hundreds of pins were connected to the chip by microscopic gold wires. And although heatsinks and fans were sometimes fitted, the chip manufacturers for a long time insisted that these shouldn’t be necessary and were most likely a sign of over-clocking. However, these days, CPU costs have been drastically slashed by radical new assembly techniques. With most microprocessors, the hundreds of connections are now made by printing tiny dabs of solder paste directly onto the silicon chip and then “sweating” this face-down onto a small multilayer PC board holding the connecting pins. The rear of the silicon chip is left bare and a heatsink must be fitted, as the CPU can draw several amps. With this model, you have to remove the heatsink to access the motherboard and I noticed that there was a layer of some sort of silver-looking “jelly” between it and the CPU, obviously some sort of high-tech heat transfer goo. But I could see clear signs that the goo layer had been previously torn and creased, presumably when someone else removed and refitted the heatsink, although “Boy Wonder” insisted that nobody had ever opened the case. Since the CPU is so heavily dependent on that heatsink, the smallest defect or void in the goo would allow that part of the chip to overheat and almost certainly make the CPU’s thermal protection cut in. I cleaned off the silvery goo with an ink rubber and applied a dab of ordinary white silicone heatsink com­­pound. I was quite prepared to find that ordinary white heatsink goo wouldn’t really cut the mustard but I figured that it might give me enough improvement to indicate whether it was worthwhile chasing down the right stuff. I had a bit of fun getting all the fiddly little connectors back in their respective sockets but eventually I got it all back together again. After that, it was as right as rain! I left it running continuously for a week and it never missed a beat. Perhaps on really hot days, the inadequacies of my two-cent repair will manifest themselves but at least I’ll know what to do if it does play up. All for nothing Not that any of this did me much good of course; once Mr Junior Executive discovered it was working again, he immediately claimed it back. You can’t win! Oh well, at least I didn’t lash out for a replacement battery; I’ll let him worry about that! SC siliconchip.com.au Impedance Matching 8 Way Speaker Selector SAVE $15 1 Farad 20V Capacitor with Voltage Display Car audio enthusiasts please note! This massive capacitor will help stabilise the voltage levels in a high power stereo installation. A voltage display keeps you informed of voltage levels, and mounting hardware is included. Cat. RU-6750 $ 95 Was $99.95 PROTECT 84. 2.4GHz Surveillance Packages Don't Covert Surveillance Packages have out on miss never been this easy. Monitor up to hot prithese ces! 100m away with this 2.4GHz package. Package includes 1 x CMOS colour camera, 1 x transmitter/receiver package and plugpack. For camera specifications see detail on website or in-store. Cat. QC-3268 $ 95 129. SAVE $119.05 Was $249.00 This package has a CMOS colour camera with IR illumination for night vision, a 2.4GHz transmitter/receiver and plugpack. Unbelievable value. For camera specifications see detail on website or in-store. Cat. QC-3269 $ 95 SAVE 139. Was $299.00 $159 4 x 100WRMS Full Range Digital Car Amplifier The latest addition to our award winning range of Response amplifiers. This true 4x100WRMS full range digital amplifier is in an ultra compact chassis - small enough to be mounted under a car seat! It is extremely high in efficiency, drawing a mere 50A in bridge mode producing a Cat. AA-0425 whopping 550WRMS of total power! $ 00 Specifications: •Power / Channel <at> 4ohm 14. 4V: 100WRMS x 4 •Power / Channel <at> 2ohm 14. 4V: 150WRMS x 4 •Power / Bridged <at> 4ohm 14. 4V: 300WRMS x 2 399. 5.8GHz Audio Video Sender Beat the congestion around 2.4GHz and enjoy the reliability and assured picture quality a powerful 5.8GHz transmitter and receiver provides. 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The ABS plastic housing features a glass lens for clear vision, LED illumination for night vision, and a ventilation fan and heater to remove moisture and eliminate condensation. See our website for our full range of professional cameras. Professional Camera Housing Cat. QC-3386 95 without IR & Heater: QC-3385 $59.95 $ Bracket to suit: QC-3387 $19.95 99. KIT OF THE MONTH Smart Fuel Mixture Display Kit This improved model has an emergency lean out alarm, better circuit protection and an auto dimming display. Kit includes PCB, and all electronic components. Picture shows Spray Controller fitted to the Display Kit. 219. Long Range 120m Twin Beam Driveway Monitor 240m range indoors! Now you can reliably monitor an entry way of up to 240m indoors, or 120m outdoors. Installation is easy thanks to built-in laser guides, and dual beams help eliminate false alarms from birds or debris etc. See website for details. Was $299.00 SAVE Cat. LA-5199 $100 $ 00 199. Four Zone Security Alarm System with Simple Two Wire Hookup The alarm is so simple to set up that DIY enthusiasts will love it! All system SAVE components $50 (sensors, sirens) are connected to the control unit via a two-core flat wire. The unit has a built-in keypad with status LED and three modes of operation (Home, Out, Off). Supplied with: •Main control unit •Two PIRs •4 Door or Window contact reed switch 8Z •External Siren •240VAC Adaptor also avone •50m two-core flat wire and clips for onlyailable $249 •Screw/wall plug packs •Main unit: 160(H) x185(W) x35(D)mm •Extra PIR to suit LA-5476 $29.95 Cat. LA-5475 $ 00 Was $199.00 149. 27. Add on Intercooler Water Spray Controller for Fuel Mixture Display kit Ref: Silicon Chip March 2006 The be Simply add these few autom st in otiv components to the Smart Fuel kits! e Mixture Display Kit (KC-5374) shown above and reduce water Cat. 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MP-3466 $ 95 69. 9. 1 NEW iPod Replacement Batteries TM IpodTM Replacement Battery Kits While iPods are incredibly popular, the lithium rechargeable batteries locked inside only have a fairly limited number of charge/discharge cycles. Once the battery starts to fail the iPod performance falls off quickly. Stereo Camcorder Microphone Improve the sound quality of your home video recordings with this unitWas $49.95 directional stereo microphone. The mic has a standard camera SAVE $30 mount base and a companion stand that enables the unit to be Cat. AM-4083 used as a table microphone as $ 95 well as a camera mounted mic. 19. SB-2576 USB 2.0 Multimedia Speakers SB-2574 Batteries to suit Mini, 1st, 2nd, 3rd and 4th TM generation iPods . SB-2570 1st/2nd generation 1600mAh ALL SB-2572 3rd generation 850mAh SB-2574 4th generation 900mAh $29.95 SB-2576 Mini 500mAh iPod Stereo Amplified Speakers with Remote See instore for our extensive range of iPod accessories Streamline design! An active speaker system for iPods, iPod Minis and Nano. Comes with interchangeable cradles to suit any iPod, it has a protective clear front lid and an Infrared iPod remote controller which controls the volume and the song selection. It also has an auxiliary input for non-iPod devices. •iPod not included Was $149.00 SAVE $10 Cat. XC-5180 $ 00 139. USB 2.0 DVD Maker No more fading memories! Transfer all of your VHS, Betamax, and camcorder tapes to DVD using your computer’s DVD burner. With editing SAVE software to add colour $30 and transitional effects, as well as sound tracks. Supports composite & S-Video Cat. XC-4809 $ 00 inputs & PAL or NTSC sources. Was $129.00 99. XPERT DVD Maker Convert all your old VHS tapes and camcorder cassettes to DVD!The Xpert DVD maker converts on the fly, so there is no need for excessive amounts of free disk space. All you need is a DVD burner and you can store your memories forever! These trendy two channel speakers plug into your computer's USB port. No need for messy cabling or external power supplies like conventional multimedia speakers. Was $34.95 AV Sender with Remote Control Extender Cat. XC-5162 $ 95 SAVE $5 29. Stereo Headphone Distribution Amp Kit Refer Silicon Chip (November 2005) This project kit enables you to drive up to two stereo headphones from any line level (1 volt peak to peak) input. The circuit features a facility to drive headphones with impedances from about 8-600 Ω. The Jaycar kit comes with all specified Cat. KC-5417 board components and quality $ 95 fiberglass tinned P.C.B. 29. Headphone Amp Power Supply Kit 349. 2 With the addition of an IR remote control repeater you can change the channel of the source device etc from the other room. Was $89.95 SAVE Cat. AR-1830 $10 $ 95 79. Extra receiver to suit Cat. AR-1831 Was $69.95 Now $59.95 Save $10 PSP Car Kit The ultimate accessory kit for the PSP. The kit includes an LCD screen protector, 2 in 1 function USB-2 Power link cable, PSP and UMD cleaning kit, car charger and a designer black leather strap. Cat. XC-5192 $ 95 29. Portable Speaker To ensure the best possilbe performance to the Headphone Amplifier kit, this power supply provides regulated ±15V and +5V outputs. Toroidal transformer required use MT-2086 Cat. KC-5418 $ 95 17. 3 Way TV Game Selector Switch with S-Video Eliminate awkward cable swapping behind your television SAVE using this 3-way $15 switcher, which handles both RCA and S-Video connectors and also features Cat. AC-1669 $ 95 a headphone output Was $24.95 3 Piece Surround Sound Add - On Was $129 This nifty little unit is compatible with iPods, MP3 players, mobile phones, portable CD players, laptops and PC's. It folds into a tiny 90(L) x 65(H) x 60(W)mm compact box and weighs only 177g. Cat. XC-5186 $ 95 29. Wireless MP3 Modulator For In-Car Use Use your USB flash drive and this clever device to play your favourite MP3 files in the car. The unit is the size of a normal car cigarette lighter plug and is fitted with a USB socket. Play your MP3 files by transmitting them to your car's FM radio or listen to an ordinary portable CD, Cat. GE-4030 DVD or MP3 player, or any $ 95 SAVE other audio sources. $10 Was $69.95 59. TFT or Plasma Screen Wall Bracket Cat. XC-4811 $ 00 99. 12" 150WRMS Powered Subwoofer Add a new dimension to your home theatre! It uses a well designed bass reflex enclosure for the best performance. Measures 375(W) x 510(H) x 410(D)mm. Was $399.00 SAVE Cat. CS-2456 $50 $ 00 SAVE Watch cable TV all over the house! $10 Send a signal from a DVD player, settop box etc., to another room, without the use of any cables! You can use as many receivers as you like, without degrading signal quality. Each unit comes supplied with stereo audio and video transmitter and receiver, mains plugpacks & RCA cables. Transmission range is up to 100m, but depends on the type of construction materials used. Was $69.95 Cat. AR-1832 $ 95 Extra receiver to suit Cat. AR-1833 Was $49.95 Now $44.95 Save $5.00 59. 9. SAVE $30 2.4GHz Wireless Audio Video Senders REDUCED TO CLEAR! Price slashed to make room in our Warehouse! The centre speaker contains a screened 4" mid/woofer and 2" tweeter with a 6 ohm impedance. The two rear speakers contain a 4" full range speaker with a 4 ohm impedance. Originally $99.95 SUPER BARGAIN Buy 2 for $29.95 Cat. CS-2465 $ 95 18. Getting the right viewing angle with LCD screens with fixed wall brackets is nearly impossible. Now we have an adjustable LCD screen wall bracket, which can tilt and swivel to get the best possible viewing angle. The great feature about this bracket is that it suits any LCD screen which uses the industry standard VESA mount fittings. •8kg capacity •Tilts up/down and swivels 180 degrees Cat. CW-2814 $ 95 ea 39. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 INTERNET> www.jaycar.com.au Flexible 12VDC 3 x SMD LED Strips Speaker Boxes Affordable high quality Subwoofer speaker boxes! Made from 17mm MDF these boxes are pre-carpeted with grey quality fabric and are internally lined with sound dampening material. They come with recessed terminal posts with 750mm pre-wired length of speaker cable. No mess, no fuss These LEDs are mounted on a flexible PCB with a 3M self adhesive backing. Ideal for illuminated signs, window displays and other small lighting applications. •Ribbon Width: 8mm •Printed Circuit Board Thickness: 0.25mm •Working Voltage: 12V DC •Working Current: 2A White Red Blue Cat. ZD-0470 $ 95 Cat. ZD-0472 $ 95 Cat. ZD-0474 $ 95 6. 10" Speaker Box 20 Litre Cat. CS-2533 $ 95 12" Speaker Box 28 Litre Cat. CS-2535 $ 95 6. Carbon Fibre Subwoofers Cat. QM-3751 $ 00 Featuring high quality Carbon Fibre cones and dual voice coils, these subwoofers offer great performance and durability. See our website for full details 269. SAVE •250WRMS power handling $10 •Dual voice coils •87db sensitivity Was $179.95 Cat. CS-2278 $ 95 169. 12" Carbon Fibre Subwoofer Cat. CS-2279 $ 00 209. 8. This temperature switch can be set anywhere up to 1200°C, so it is extremely versatile. The relay can be used to trigger an extra thermo fan on an intercooler, mount a sensor near your turbo manifold and trigger a simple buzzer or light to warn you of high temperature. The LCD displays the temperature all the time, which can easily be dash mounted. Cat. KC-5376 $ 95 69. Independent Electronic Boost Controller Change between 2 completely different boost maps at the flick of a switch. Boost curve selection is via a dashboard switch & it is all programmed using the Handheld Digital Controller - KC-5386. Kit supplied with PCB, machined case, and all electronic components. Suitable for EFI and engine management systems only 24. Frequency Switch Kit 149. Kevlar Cone Coaxial Speakers Fantastic quality! This range of coaxial speakers offer high performance and great looks. They have a large super tweeter and their Kevlar cones take them into a realm of their own. SAVE $10ea Cat. •40WRMS power. CS-2320 •86.5dB sensitivity. $89.95 Was $99.95 5" Kevlar 2 Way Cat. KC-5378 $ 95 35. INTERNET> www.jaycar.com.au Power Handling: 60WRMS Impedance: 4 Ohms Voice Coil Resistance: 3.3 Ohms Sensitivity: 87.8dB/Wm Cat. CS-2329 $ 95 pr 4" Kevlar 2 Way Cat. KC-5382 $ 95 Relay activation! Switch a relay on or off depending on the frequency of the input. This could be used as a shift-light, over speed warning & more. Kit includes PCB and all electronic components. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 19. Save a fortune over pre-built units! Use it with an injector to fire nitrous fuel into your engine, or control an electronic water pump etc. Hundreds of uses! Kit includes PCB and all electronic components. 79. Power Handling: 60WRMS Impedance: 4 Ohms Sensitivity: 88.2dB/Wm 6.5" Response Precision Kevlar Splits Nitrous Fuel Mixture / Motor Speed Controller Cat. KC-5387 $ 95 6" Response Precision Kevlar Splits 139. Cat. BS-5080 $ 80 We have a massive range of quality automotive kits The included outboard crossover features high-grade internal components with variable tweeter attenuation for system tuning and polyswitch overload protection. These splits represent a true bargain for those looking for an affordable true sound quality speaker system. Cat. CS-2327 $ 00 pr HIGH PERFORMANCE ELECTRONIC PROJECTS FOR CARS High Range Adjustable Temperature Switch SAVE $11 KELVAR CONE COAX SPLITS 199 Over 160 pages! The Performance Electronics for Cars Book from Silicon Chip publications has chapters on modification and theory, as well as the 16 projects. High to Low Level Converter •Wire speaker outputs to RCA inputs. SAVE $6 •Adjustable levels. Was $23.95 Cat. AA-0480 $ 95 Cat. QP-5030 $ 95 SAVE $150 Having a viewing angle of 150 degrees and supplied with both power and video leads combined within the one cable, this rear-view vision camera is simple to install and ready to plug directly into you monitor. Designed for use with any in-car monitors. See instore for our full range of TFT vehicle monitors. Cat. QC-3451 $ .00 PERFORMANCE ELECTRONICS FOR CARS BOOK SAVE $15 It only requires power, and the blue look will enhance any unit it is mounted into. Face measures 40 x 40mm. Was $19.95 In Vehicle Flush Camera 10" Carbon Fibre Subwoofer 34. Blue 0-25VDC Analogue Panel Meter Ideal for rear seat viewing! It has integrated dome lights in the console, so you can replace your factory interior light. Was $419.00 69. •3 digit LED display. •4 individually fused outputs. Wafer Fuse Style Cat. SZ-2076 5AG Fuse Style Both Types (ea) Cat. SZ-2077 $ 95 Was $49.95 17. Roof Mount 7" Monitor 49. SAVE •300W RMS $10 •Dual 4-ohm voice coils •88. 2dB sensitivity Was $219 6. Gold Distribution Blocks with Voltage Display Cat. •50WRMS power. CS-2322 •89.5dB sensitivity. $99.95 Was $109.95 6.5" Kevlar 2 Way Cat. •75WRMS power. CS-2324 $ 95 •91.3dB sensitivity. 109. Was $119.95 6" x 9" 2 Way Cat. •80WRMS power. CS-2328 •93.5dB sensitivity. $ 129.59 Was $139.95 3 2.4GHz Wireless Colour LCD Receiver The receiver incorporates a 45mm colour screen and speaker so you can both see and hear your baby. Receiver can also be powered by the mains adaptor (included) for use in fixed locations. The camera has IR for night vision capability, a microphone and can be battery or mains adaptor powered. Was Cat. QC-3280 SAVE $ 00 $299.00 $100 Housed in a strong die-cast aluminium base and L-shaped bracket with a reinforced polycarbonate dome, these vari-focal dome cameras are extremely rugged to withstand the harshest of environments. See our website for full specifications. 199. 149. Colour Video Doorphone Top quality! The colour camera, and LCD screen give you excellent clarity to the picture. Supplied with all mounting hardware and wiring. Was $359.00 Expand the system! Buy an extra colour receiver QC-3607 with your video doorphone for just $129.00. Save $120! Cat. QC-3606 $ 00 299. SAVE $60 Video Doorphone with Colour LCD Monitor Features a 5.6" colour TFT-LCD screen. The external unit consists of a colour CMOS camera, speaker, microphone and call-button housed in a SAVE strong plastic case. Other $100 features include a Warning button that sounds an alarm through the outside panel and a Monitor feature so you can seen what's happening at the door whenever you wish. Accessories include a 15m interconnecting cable, volume and contrast controls plus a Cat. QC-3612 $ 00 plug pack power supply. Was $499 399. Colour Wireless Video Door Phone 2.4GHz This system is neat and feature packed. The compact internal unit houses a clear 1.8" LCD display, control buttons and can accommodate up to 4 cameras which can be mounted up to 30m away from the receiver. The camera has IR illumination so you can identify who is at the door even in poor light conditions. With this system, you can see who is at the door, answer the door from anywhere in your premises and let them in should you use the optional door strike release. •Package includes one camera, monitor and mounting hardware. Was $599 Cat. QC-3625 SAVE $ 00 $100 499. CMOS Camera 2.4GHz to suit above 4 Cat. QC-3294 $ 00 229. Cat. QC-3626 $299 SAVE $5 Was $29.95 SAVE $5 Metal mounting for stability. Dome Dummy Camera with Right Angled Bracket Highly noticeable for Was $19.95 maximum deterrent. Cat. LA-5311 $ 95 14. Fake Alarm Kit No one will know that you don't have the full system. Looks like the real thing and the bad guys will move on to an easier target. Was Cat. LA-5130 $47.50 $ .50 169. Cat. QC-3602 $ 00 24. Dummy Camera Disguised as a Smoke Detector Featuring a Sony CCD sensor this camera is ideal for covert, indoor surveillance applications. Cat. QC-3555 $ 00 B&W Video Doorphone $50 Extremely realistic! Both models can have standard board cameras fitted to make them real working cameras. Corner Mounting Cat. LA-5312 $ 95 Colour CCD Camera DOOR PHONES See who’s at your door before you let them in! The 4" screen lets you see your visitors, and you can talk to them through the handset. Supplied with all mounting hardware and wiring. SAVE Was $199.00 Realistic Dummy Dome Cameras Colour Dome Camera Vari-Focal with L Bracket 37 Wireless Intercom with Door Strike Release SAVE $10 Large Surveillance Warning Sticker Open the door from anywhere! This great unit acts as an intercom, with a wireless receiver. Take it out the back, or around the house. It also has electronic door strike control, so you can let your visitors in! SAVE Was $129.00 $20 This label will leave no doubt that your vehicle or premises are fully Cat. LA-5102 $ 25 protected. 2. Cat. AI-5510 $ 00 109. Shed / Garage / Boat Alarm SAVE Very affordable! $10 The garage or shed can often be neglected when it comes to security, but often there is valuable machinery and tools inside. This unit consists of a reed switch for the main door, and a PIR for general protection. Keyfob arm / disarm. Includes mains plugpack, Cat. LA-5400 95 10m cable, and a battery backup option. $ Was $49.95 39. 3 Zone Wireless Home Alarm Ideal for tenants! The system is supplied with a control panel equipped with keypad, and a built-in siren. It also comes with a wireless PIR, reed switch, and panic button which operate within a 50m range. There are also provisions for hard-wired expansion if desired. Cat. LA-5125 See our catalogue or website $ 00 for full specifications. 199. RFID - SECURE ACCESS WITHOUT KEYS! Radio Frequency Identity (RFID) is a contact free method of controlling an event such as a door strike or alarm etc. An ‘RFID Tag’ transmits a unique code when energised by the receiver’s magnetic field. As long as a preprogrammed tag is recognised by the receiver, access is granted. RFID Keypad Access Controller RFID Security Module Receiver Kit A card capacity of up to 500 RFID cards. It is designed to control door strikes in home or business access control installations. The unit allows 4 entry method, password, proximity card, password + proximity card and egress push button entries. See our website for full specifications. Ref: Silicon Chip June 2004. Provides normally open, normally closed electrically switched outputs. SuppliedPCB will mount behind standard wall plate. Kit supplied with PCB, tag, and all electronic components. Cat. LA-5123 $ 00 RFID Access Control System 169. No contact required! Control entry to a doorway, or an entire building. The unit can be used in a network of locks administered by a central location, or just to control access through a front door. It is 12V powered, so you can use it in remote locations, and the reader unit is splash proof. Was $199 •5 RFID cards included. Cat. LA-5120 SAVE •N.O. and N.C. relay $ 00 $10 contacts. Includes 1 Keyfob RFID tag worth $9.95 absolutely FREE! See below for extra tags. Cat. KC-5393 $ 95 89. RFID Tags Keyfob Style These tags transmit a 40 bit unique code and are EM-4001 compliant. Two styles available: 189. Cat. ZZ-8950 $ 95 9. Credit Card Style Cat. ZZ-8952 $ 95 5. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 INTERNET> www.jaycar.com.au Avoid nasty burns. Displays the actual temperature of the water coming through the spout. Displays 0 to 50°C (32 - 122°F) in 1° steps. Cat. GH-1350 SAVE Was $ 75 $7 $14.95 7. Shower head with LCD Temperature Read-Out - White Tells you the water temperature before you get in the shower & helps prevent scalding. Was $24.95 SAVE $10 Cat. GH-1354 $ 95 14. Multi-Function Torch Warning Light SAVE $10 This weather station has an unbeatable range of features. The system measures inside and outside temperature, air pressure, rainfall, humidity, wind speed, direction, and chill factor without messy wiring. Visit Jaycar to •0 to 100kl/h wind view our extensive Speed range of weather •-40 to +60 outdor temp stations! •Predicts weather trend Was $249 Cat. XC-0293 SAVE $ 00 $50 199. Wind Powered Generator Experimenters Kit Cheap short distance communication! They operate up to 5km in an open field, or 1km in the city. Lots of accessories available, see our website for details. Cat. DC-1010 or 2 for $ 95 Digital Map Distance Calculator Features a bright Quartz halogen globe, swivel handle and adjustable stand, lever style power switch for hands-free use, high-impact ABS plastic weatherproof body. The internal SLA battery can be charged through your car's cigarette lighter or by the supplied plug pack. Was $79.95 Cat. ST-3306 $ 95 69. 34. Cat. KJ-6696 $ 95 44. 34. $5 Installing wall and ceiling speakers or recessed lighting is now a lot easier with these unique adjustable holesaws. These saws are designed to cut through plaster board and ceiling tiles and features calibrated adjustments to make hole -size selection a breeze. The blades are carbide coated and self sharpening. Two sizes available. •Drill not included. Cat. TD-2520 $ 95 69. INTERNET> www.jaycar.com.au Massive range! This high-quality light-weight UHF transceiver is ideal for use in many professional and leisure activities. Up to 8km working range with a hi/lo setting to conserve power. Was $89 Cat. DC-1040 SAVE $ $10 79 Rechargeable 40 Channel UHF Transceiver SAVE $10 Great range, great features! SAVE Since the outstanding success of $10 our popular DC-1010 transceiver, it only seemed logical to refine the design, addng a few enhancements along the way. It is a lot Buy an extra more compact, transceiver measuring just 53(W) x (DC-1028) for 95(H) x 32(D)mm. It uses a just $49.95! small rechargeable battery Save $20! pack, and is supplied with a dual charging cradle. You can still of course use AAA batteries as a backup. Four step scrambling is also provided for private communications, making this transceiver just plain fantastic! Supplied with one transceiver and a Cat. DC-1025 $ 95 charging cradle. Was $59.95 49. Adjustable Holesaws 62 to 177mm hole size $59.90 1.5W High Powered UHF CB Transceiver This durable torch may be small but it makes up for its size in the light output. It contains 21 high intensity LEDs and features a rigid body which makes it easy to grip and incorporates a twist on/off switch. 4 x AAA batteries (not included) Was $39.95 Cat. ST-3394 SAVE $ 95 FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 40 Channel UHF CB Band Transceiver 69. 21 LED Hand Torch Wireless Weather Station A great learning tool! This small scale project enables you to build a real working wind generator, and then use it for experimenting. It can supply up to 10VDC <at> 100mA (depending on wind speed), and features an on-board 330uF capacitor so you can store the energy for later use. Kit includes all parts to SAVE make the generator, fan $5 assembly, and pedestal. Stands 250mm high. Was $49.95 179. 10 Million Candle Power Spotlight Flashing LED Headlight 29. These brilliant scales can weigh up to 1Kg with 0.1g Accuracy. This unit also features a counting function usually reserved for high end commercial scales costing many times this price. Readout is in grams, ounces, and penny weight with auto shut off and low battery indicator. Requires 3 x AAA batteries (not included). Counts individual items in multiples of 1-200. Unit size 140(L) x 80(W) x Cat. QM-7242 $ 95 25(H) mm 14. $10- This bright headtorch is ideal for working or riding a bike in poor light conditions. It also features four red LEDs so it can act as an illuminator or warning light. With a strong magnetic base it be attached on to steel surfaces. Requires 4 x AAA batteries. Cat. ST-3318 Was $39.95 $ 95 Simple and accurate! Useful for checking pH levels in water, fish tanks, swimming pools, and more! It is great in a chemical lab for testing and checking solutions, and the large LCD is easy to read. It has a range of 1 - 14pH, 0.1pH resolution and +/- 0.2pH accuracy. Was $74.95 SAVE Cat. QM-1670 $5 $ 95 How far is the next turn off? Automatically convert a map’s scale distance to real distance by rolling the small wheel along the desired route. It works with any map scale and displays in kilometres or miles. Was Cat. XC-0375 SAVE $ 95 $19.95 $5 Stay safe in emergencies! Breakdowns & flat tyres at night can be dangerous and the more warning you can give other drivers of your presence, the safer you will be. It features a torch, flashing LED light, with a magnetic and tripod type base. Cat. ST-3875 SAVE 95 Was $39.95 $ 29. Pocket Scales 1kg 0.1g Resolution with Count Function Digital PH Meter with LCD Hand Shower Thermometer with LCD display 158 to 264mm hole size Cat. TD-2522 $ 95 79. Mini Laboratory Magnifier Lamp Consisting of a 90mm diameter lens and a 12 Watt circular globe enclosed behind a clear protective housing mounted on a 300mm flexible gooseneck. Lens magnification is 3 dioptre. (Replacement fluoro tube QM-3521 $9.95). SAVE Was $69.95 Cat. QM-3520 $20 $ 95 49. Desk Clamp Magnifier Light This is a high quality, all metal frame construction magnifier which features a 22 watt circular fluoro built inside the magnifier head. The magnifier itself is a 3 dioptre lens. Total extended length 990mm. Was $109.00 Cat. QM-3525 (Replacement fluoro $ 00 tube QM-3523 $13.95) SAVE $10 99. 5 WITH OUR EXTENSIVE RANGE OF INVERTERS, YOU ARE SURE TO F I N D T H E R I G H T I N V E R T E R TO S U I T Y O U R N E E D S Dual Battery Isolator This unit will direct alternator charge current to your main and auxiliary battery when the engine is running. When you are stationary and drawing power (for fridges etc.), the unit will isolate one battery before both batteries go flat, enabling you to start your vehicle the next morning. 1500W Pure Sinewave Inverter 24VDC to 230VAC Cat. MB-3670 $ 95 99. Battery Fighter Chargers Designed to fully charge and maintain a lead acid battery at the correct storage voltage without the damaging effects caused by trickle charges. Ideal for vintage cars, boats or planes that sit for months at a time without use. Lack of use causes a lead-acid battery to self discharge and may result in destroyed cell. A replacement battery in some instances will cost more than these chargers. Cat. MB-3602 $ 95 MB3600 79. Battery Fighter® Super Smart 12V SLA Charger Battery Fighter®12V SLA Battery Charger - 1. 25A Cat. MB-3600 $ 95 49. Rapid AA/AAA Battery Charger This rapid 2 hour fast charger is designed specifically for Ni-MH AA or AAA batteries. Cat. MB-3513 $ 95 39. Sealed Lead Acid Batteries High quality batteries! Our range of SLA batteries represent excellent value for money. They feature leak proof construction, long service life, high discharge capability, deep discharge recovery, and more. Don’t use low quality SLA batteries to save a dollar or two, you will just end up replacing them even sooner. 6 Volts 6 Volts 12 Volts 12 Volts 12 Volts 4.2Ah 12Ah 1.3Ah 2.2Ah 4.2Ah 12 Volts 7.2Ah 12 Volts 18Ah SB-2496 SB-2497 SB-2480 SB-2482 SB-2484 NOW $29.50 SB-2486 NOW $19.95 SB-2490 NOW $40.45 NOW $12.95 NOW $29.95 NOW $19.95 NOW $24.95 Was $35.00 Save $5.50 Was $36.50 Save $16.55 Was $44.95 Save $4.50 New 13.8VDC Lab Power Supplies MP-3096 MP-3097 MP-3098 MP-3099 Output (VDC) 13.8 13.8 13.8 13.8 Rated Output (amps) 5 10 20 30 Surge Current (amps) 7 12 22 32 Voltage regulation <5% <5% <5% <5% Ripple Voltage 100mV 120mV 150mV 150mV Can be used in 24V installations and delivers a constant 1,500 watts at 230VAC with short term bursts up to 2,500 watts. It features electrical isolation between battery and mains voltage for increased safety. Was $999 SAVE $100 Cat. MI-5089 $ 00 899. Can Sized 140W 12VDC to 230VAC Inverter Utilising the existing drink holders in cars, this inverter is held in place and doesn't need any modifications to vehicles. Featuring a 140W power output, this unit has the capability to run laptop computers and other Cat. MI-5120 $ 95 equipment. 69. 300W Modified Sinewave Inverter 12VDC to 230VAC Typical Application include for use with Laptop computers, recharging power tools or batteries, lamps and fluorescents up to 300W, 34cm televisions etc. All our inverters are electrically isolated between the battery and secondary voltages. Beware of cheaper models that aren't! 400W Modified Sinewave Inverter 24VDC to 30VAC SAVE $10 Cat. MI-5104 $ 95 89. Was $99.95 Cat. MI-5107 $ 95 149. Delivers up to 400 watts of continuous power, while supplying surge currents up to a 1200 watts. Was $169.95 SAVE $20 S TA R M O D U LE S & A C C E S S O R I E S Super Bright 1 Watt LED Star Modules These LEDs are just as bright as the leading brand but cost a whole lot less. They are increasingly finding their way into general and architectural lighting applications and with a service life of 100,000 hours. They provide up to 25 lumens per watt and are available in a number of colours. 1 Watt LEDs 3 Watt LEDs Super Bright Star Module - Red Cat. ZD-0500 Super Bright Star Module - Amber Cat. ZD-0502 Super Bright Star Module - Green Cat. ZD-0504 Super Bright Star Module - Blue Cat. ZD-0506 Super Bright Star Module - White Cat. ZD-0508 Super Bright Star Module - Warm White Cat. ZD-0510 Super Bright Star Module - Red Cat. ZD-0520 Super Bright Star Module - Amber Cat. ZD-0522 Super Bright Star Module - Green Cat. ZD-0524 Super Bright Star Module - Blue Cat. ZD-0526 Super Bright Star Module - White Cat. ZD-0528 Super Bright Star Module - Warm White Cat. ZD-0530 3 WATT LEDS $ 95 1 WATT LEDS $ 95 23. 12. Wide and narrow beams! These lenses are used to evenly distribute light in the desired way. Wide beam lens Cat. ZD-0420 Narrow beam lens Cat. ZD-0422 9. A collimator is an optical device which is designed to produce a light beam in which the the rays are parallel, or at least very near parallel. While we normally consider LEDs to be very focused in terms of light spread, in many applications there is still a vast quantity of "wasted" light spread.This series of collimators are designed to suit our Star LED modules (lambertian LED models only) and are manufactured from quality optical components. 3 different viewing angles are available: Cat. HP-1290 Collimator - 10° $ 95 10° Viewing Angle 5. Collimator - 15° Cat. HP-1292 $ 95 Collimator - 25° Cat. HP-1294 $ 95 15° Viewing Angle 25° Viewing Angle 5. 5. Pre Built Luxeon LED Power Module An affordable power supply for Luxeon LEDs! This pre-built module can power 1, 2, or 3 1W Luxeon LEDs from a DC supply of between 11 and 30V. Cat. AA-0580 $ 95 39. Luxeon Star LED Driver Kit Refer: Silicon Chip May 04. Luxeon high power LEDs are some of the brightest LEDs available in the world. Cat. KC-5389 $ 95 They offer up to 120 lumens per unit, and will last up to 100,000 hours! This kit allows you to power the fantastic 1W, 3W, and 5W Luxeon Star LEDs from 12VDC. This means that you can take advantage of what these fantastic LEDs have to offer, and use them in your car, boat, or caravan. Luxeon LED Lenses Cat. ZD-0420 $ 95 Collimators 29. Cat. ZD-0422 $ 95 9. Luxeon Star Power Supplies 5 Amp Cat. MP-3096 $ 95 89. 6 10 Amp Cat. MP-3097 $ 95 119. 20 Amp Cat. MP-3098 $ 95 169. 30 Amp Cat. MP-3099 $ 00 219. These 240 Volt power packs simplify the power requirements of Luxeon LED's. An ideal power source for photographic light boxes or decorative applications. There are a few types to satisfy your lighting needs. •Dimensions: 102 x 21 x 43mm •Lead Lengths 1800mm on the wall socket side and 950mm Luxeon Side Cat: Voltage Current Unit: 10 VOLT 20 VOLT 1 Watt x 3 MP-3270 10V 350mA Cat. MP-3270 Cat. MP-3272 1 Watt x 6 MP-3272 20V 350mA $ 95 $ 95 3 Watt x 1 MP-3274 3.5V 800mA 19. 24. 3.5 VOLT Cat. MP-3274 $ 95 19. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 INTERNET> www.jaycar.com.au Low Cost Multimeter IDEAL True RMS DMM This is a full featured meter with probes and transistor tester! Includes: Was $9.95 •19 range / 3.5 digit •Transistor/diode test •10A DC current SAVE Cat QM-1500 $2 •High speed analogue bargraph. •Relative measurement. •Duty Cycle. •Cat III 600V. •Limited lifetime warranty. Cat. QM-1625 Was SAVE $ 00 $399 $50 Balloon Adventures 349. 7.95 Backlit Temp DMM $ Double Insulated Probe Style DMM A great all round meter! Includes data hold, backlight and hold function. Other features include: Cat. QM-1526 $ 95 •Continuity buzzer •Temperature probe SAVE •Auto power off $5 Was $24.95 19. True RMS Auto Ranging DMM Measures true RMS measurement, temperature, capacitance SAVE and much more. $10 Cat QM-1536 $ Was $79.95 69.00 Digital Multimeter with Holster - Protek 506 An excellent high end digital multimeter with a host of functions including true RMS readings, frequency, inductance, memory, data hold and much more. See website for full details. SAVE Cat. QM-1290 $10 $ 95 Was $189.95 Make readings from DIL package ICs a whole lot easier by reducing the possibility of shorting out pins with the SAVE test probe. The data hold switch is $5 conveniently placed for quick activation. Each range is manually selected, with a range table printed on the front of the probe for easy reckoning. The probe is double insulated for added safety. See our website for full specs. Cat. QM-1497 $ 95 Was $19.95 14. True RMS Auto Ranging RS-232 DMM Features a groovy red backlit screen, and a host of features. Includes optical RS-232 computer interface and PC software to store measurements on your home, workshop, or notebook computer for later analysis. Please see our website or catalogue Cat. QM-1537 for full specifications. $ .00 Was $99 SAVE $10 Non-contact! It measures up to 99,999RPM, and can be used to measure RPM or simply count revolutions. It has a large LCD display, laser pointer, and min/max recall. Great for the mechanics workshop or handyperson. Cat. QM-1448 Was $69.95 SAVE $ 95 Simple tester for a simple problem. Don’t get caught with a faulty spark plug. Bright neon illumination indicates spark presence. Cat. QP-2264 $ .95 $10 59. $ $ $ S AV E O N O S C I L LO S C O P E S $ $ $ 10MHz Single Trace Budget CRO With Probes DIGITECH CRO 40MHz Dual Trace W/Probes SAVE $221 A useful CRO for the busy serviceman or workshop. Features 20Mhz bandwidth. Supplied with 2 sets of probes. This instrument is ideal for the professional who only needs to use a CRO occasionally. It is also ideal for the dedicated enthusiast. It features a powdercoated steel case, 75mm CRT with 5mm square graticule, combined tilting bail / handle. Scope probes 1 x, 10 x are included. See our website for full Cat. QC-1910 specifications. Was $379 $ 00 158. CRO 20MHz Dual Trace A useful CRO for the busy serviceman or workshop. Features 20Mhz bandwidth. Supplied with 2 sets of probes. See website for full specifications. Cat. QC-1908 $ 00 Was $698 399. The ideal CRO for the busy workshop. Features 40Mhz bandwidth and a big clear screen. Supplied with 2 sets of probes. See website for full specifications. Was $999 Quantities strictly limited - call your store first to ensure stock is available - no rain checks, no store transfers. The Velleman Personal Oscilloscope is ideal for hobbyists, students, service people, automotive applications & general development. Ask in store for full details. Was $349.00 SAVE $299 Cat. QC-1916 $ 00 299. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 INTERNET> www.jaycar.com.au SAVE $50 54. Crystal Pro - Crystal Kit This kit teaches all about the composition of crystals by growing your own large, beautiful crystals with complex shapes and fantastic colours. Was $59.95 Cat. KT-2518 $ 95 SAVE $5 54. Kite Dynamics - Kite Building and Experiment Kit SAVE $10 Soar to new heights with a kite you design and build yourself! A unique connector system allows almost limitless design Cat. KT-2514 possibilities. $ 95 Was $99.95 Micro TREK takes you on a journey through the microscopic world. Discover hidden creatures and normally unseen structures, and learn how to use a SAVE microscope and about $20 each of its parts. Was $169.95 Cat. KT-2520 $ 95 149. Alternative Energy Model House with Experiments The kit focuses on sources of heat and light from the sun and energy from wind. Electromechanical and plant energy sources are also investigated. Kit contains materials to make (among other things), SAVE a sun furnace, heat trap (greenhouse), $50 energy converters, windmill generator, solar cooler, water desalinator, electric generator, etc. Cat. KT-2502 $ 00 Was $299.00 249. Cat. QC-1901 $ 00 699. SAVE $300 10MHz Velleman Personal LCD Handleld Oscilloscope Cat. KT-2506 $ 95 Micro TREK - Journey into Microspace Digital Optical Tachometer Neon Spark Plug Tester SAVE $5 Take a balloon adventure through topics in physics, chemistry, and biology. Race balloon powered cars, fly a balloon helicopter and puncture a balloon without popping it. Was $59.95 89. 89 179. 5 THAMES & COSMOS EDUCATIONAL KITS SLASHED Minds Eye - Optical Illusions and Human Perception Astonish yourself with optical illusions as you explore the science of human perception. Find a blind spot within your eye, and watch things Cat. KT-2504 disappear. $ 00 Was $149.00 129. SAVE $20 Detector Radio Based on the principal of early crystal radios. Learn about HF coils, capacitors, resistors, and diodes. Discover how antennae work. Was $59.95 Cat. KT-2508 $ 95 SAVE 54. $5 7 VELLEMAN Pic Programmer / Checker Built and Tested! Supporting 8p, 14p, 18p, and 24p PIC microcontrollers, this board is quite versatile. It includes test buttons and LED indicators for on-board experimenting and testing, as well as programming software. Includes a PIC16F627. Cat. XC-4402 $ 00 119. VELLEMAN USB Controlled Interface Kit No parallel, no problems! This interface kit offers 5 digital and 2 analogue inputs, as well as 8 digital and 2 analogue outputs! That is plenty for experimenting and interfacing with your home or devices in many ways. It is powered straight from the USB port, and even has on-board test functions. The kit is supplied with all components, silk screened PCB, assembly manual, and software. You will not Cat. KV-3600 be disappointed. $ 95 69. YOUR LOCAL JAYCAR STORE Freecall Orders: Ph 1800 022 888 NEW SOUTH WALES Albury Ph (02) 6021 6788 Alexandria Ph (02) 9699 4699 Bankstown Ph (02) 9709 2822 Blacktown Ph (02) 9678 9669 Bondi Junction Ph (02) 9369 3899 Brookvale Ph (02) 9905 4130 Campbelltown Ph (02) 4620 7155 Erina Ph (02) 4365 3433 Hornsby Ph (02) 9476 6221 Newcastle Ph (02) 4965 3799 Parramatta Ph (02) 9683 3377 Penrith Ph (02) 4721 8337 Silverwater Ph (02) 9741 8557 St. Leonards Ph (02) 9439 4799 Sydney City Ph (02) 9267 1614 Taren Point Ph (02) 9531 7033 Wollongong Ph (02) 4226 7089 VICTORIA Coburg Ph (03) 9384 1811 Frankston Ph (03) 9781 4100 Geelong Ph (03) 5221 5800 Melbourne Ph (03) 9663 2030 Ringwood Ph (03) 9870 9053 Springvale Ph (03) 9547 1022 Sunshine Ph (03) 9310 8066 QUEENSLAND Aspley Ph (07) 3863 0099 Mermaid Beach Ph (07) 5526 6722 Townsville Ph (07) 4772 5022 Underwood Ph (07) 3841 4888 Woolloongabba Ph (07) 3393 0777 AUSTRALIAN CAPITAL TERRITORY Canberra Ph (02) 6239 1801 TASMANIA Hobart Ph (03) 6272 9955 SOUTH AUSTRALIA Adelaide Ph (08) 8231 7355 Clovelly Park Ph (08) 8276 6901 WESTERN AUSTRALIA Perth Ph (08) 9328 8252 NORTHERN TERRITORY Darwin Ph (08) 8948 4043 NEW ZEALAND Christchurch Ph (03) 379 1662 Glenfield Ph (09) 444 4628 Hamilton Ph (07) 846 0177 Manukau Ph (09) 263 6241 Newmarket Ph (09) 377 6421 Wellington Ph (04) 801 9005 Freecall Orders Ph 0800 452 9227 8 WARNING Universal Voltage Switch Kit Automatic device switching! Use it to trigger cooling systems, fans,and more from sensors. This can include temperature sensors, throttle position sensors and more. Kit includes PCB and all electronic components. Smart Card Reader/Programmer Kit Cat. KC-5377 $ 95 29. Lead Acid Battery Zapper Kit Extend the working life of your lead acid battery! Ref: Silicon Chip July ‘05 Produces bursts of high-energy pulses to help reverse the damaging effects of sulphation in "wet" lead acid batteries. This is particularly useful when a battery has been sitting for a length of time without use. Its effects are dependent on the batteries condition and type, but the results can be quite impressive. Kit supplied with case, silk screened lid, leads, inductor Cat. KC-5414 and all electronic $ 95 components. 39. Speaker Bass Extender Kit Ref: Silicon Chip April 2005. Most audiophiles know that loudspeaker enclosures have a natural frequency rolloff which is inherent in their design. The Bass Extender kit boosts the level of the bass to counteract the natural rolloff of the enclosure, producing rich, natural bass. It gives an extra octave of response, and is sure to please even the most avid audiophiles.•Kit supplied with PCB, and all electronic components. Cat. KC-5411 $ 95 19. Excellent functionality! This kit indicates via LED when the beam is broken.Includes PCB, IR RX/TX diodes, Cat. KG-9094 magnifying lens & all electronic components. $ 95 11. "Clock Watchers" LED Clock Kits These clocks are hypnotic! Ref: SC June 2005. They consist of an AVR driven clock circuit, that also produces a dazzling display with the 60 LEDs around the perimeter. It looks amazing, but can't be properly explained here. We have filmed it in action so you can see for yourself on our website! Kit supplied with double sided silkscreened plated through hole PCB and all board components as well as the special clock housing! Available in Red (KC-5404) and Blue (KC-5416) EXCLUSIVE TO JAYCAR Cat. KC-5404 $ 00 129. PRICES VALID TO END MARCH 2006 Cat. KC-5416 $ 95 189. Cat. KC-5361 $ 95 49. Once again please be reminded that we cannot accept any responsibility for the use of these devices in other than legitimate activities. Annunciator Kit 5m IR Light Barrier Kit •188mm diameter Ref: Silicon Chip July 03 Jaycar has noticed a substantial increase in sales of the KC-5361 Smart Card Programmer Kit & ZZ-8800 Programmable Gold Wafer Card. We strongly suspect that this maybe due to persons unknown some how using these products to make unlawfully generated access codes for the latest cable T.V. set top boxes. We also wish to advise that we discourage this activity. For those legitimate users, the KC-5361 Programmer Kit $49.95 & ZZ-8800 Smart Card $7.95 are back in stock. Cat. ZZ-8800 $ 95 7. Exclusive to Jaycar Ref: Silicon Chip Dec 05 Need people to take a number when waiting to be served? This electronic signaling device has digits 75mm high, each using 28 high intensity red LEDs. The numbers display from 00 to 99 is incremented by pressing a button on the separate small control box. The annunciator features a built in piezo buzzer to produce a short 'beep' each time the display is updated. Kit includes: PCB, Case and all Cat. KC-5420 electronic components. $ 95 Power: Regulated 12VDC 59. The SHORT CIRCUITS LEARNING SYSTEM The Short Circuits learning system is a great way to learn electronics. It is fun, informative, and you build great projects along the way. Here is just one from Short Circuits 3… Guitar Practice Amplifier Kit Don’t annoy the neighbours! It has a guitar type input socket, small speaker, and volume control. It sounds great! Kit supplied with PCB, speaker, socket, and all electronic components. Instructions are in the Short Circuits 3 book. Cat. KJ-8092 $ 50 14. FOR INFORMATION AND ORDERING TELEPHONE> 1800 022 888 INTERNET> www.jaycar.com.au PRODUCT SHOWCASE LeCroy enters the low-cost DSO market LeCroy Corporation, represented by TRIO T&M Solutions, has launched their new line of WaveJet digital oscilloscopes. The WaveJet provides unmatched performance in a portable scope and is an exceptional value. WaveJet’s 500K memory on each channel provides up to 200 times the capture time of other products in its class and is the first entry by LeCroy into the sub-$5,000 market. The unit offers GS/s acquisition speeds into long 500K memory at a prices normally associated with either fast sample rate but short memory, or slower sample rate of 100MS/s and typically 100K-125K memory. The 100MHz, WJ-312, offering 1GS/s and 500K memory per channel is priced at $4,495 ex GST. The new WaveJet series comprises a line up of eight models offering both two and four channel models with bandwidths of 100MHz, 200MHz, 350MHz and 500MHz, all with a maximum sample rate of 2 GS/s combined with the 500K channel memory This long memory provides a capture time of 250ms at maximum sample rate, while other oscilloscopes in this class offer capture times of only 1.25ms at the same sample-rate. WaveJets also feature a large 7.5” colour display and USB connection, both of which are typically found in higher classes of oscilloscopes. siliconchip.com.au Just recently, fake Motorola MJL21193/94 power transistors have come to light on the Australian market. These popular and normally very rugged power transistors have been featured in a number of past SILICON CHIP audio power amplifiers and are widely used elsewhere. Here’s how to spot the differences between the genuine item and the fakes. Both have very similar black plastic encapsulations but the fakes have the brand and type number info on a panel which is quite shallow compared to the deep impression on the genuine item. The leads on the fake items are flimsier and they are tapered on the two outer legs rather having a square step about 2mm from the encapsulation. The photos show the story. Contact: Trio Test & Measurement 10 James St, Thebarton SA 5031 Tel: 1300 853 407 Fax: 1300 853 409 Website: www.triotest.com.au Jaycar returns to its “Gore Hill” roots; opens new Hornsby store Jaycar’s “iconic” Gore Hill (Sydney) store, one of the first in the now-nationwide chain, has reopened at 188 Pacific Highway, St. Leonards, totally refurbished and expanded. Parking facilities have also been expanded and provide easy access to the store. Jaycar has many years of retail experience in the area and a proven product range covering home and car alarm systems, test equipment, video surveillance, car audio, electrical & electronic tools, wire, cable, accessories, hobbyist kits, and electronic equipment. Gary Johnston, Jaycar’s Managing Director, said “This site has always been popular with our customers and we are pleased that we have been able to return.” Jaycar’s new Gore Hill store is open 7 days. Phone (02) 9439-4799. Fake power transistors could be costly And yet another Jaycar store has been opened in the northern Sydney suburb of Hornsby. Pictured below, it is located at 130 George St, just 300m from the Hornsby railway station. Phone number is 9476-6221. A full list of Jaycar store locations can be found on the Jaycar website at www. jaycar.com.au R R T T More seriously, the metal mounting base on the fakes is not flat, meaning that you can never get a good mounting to a heatsink and the resulting heat transfer would be very poor, leading to early failure. No doubt the most important part, the internal chip, is also substandard. Our thanks to Jaycar Electronics and to Rod Elliott (www.sound. westhost.com) for their assistance in preparing this report. R Two genuine transistors sit perfectly flush back-to-back. With the fakes held the same way, you can actually see light coming through in uneven patches! T March 2006  61 Bargain 20MHz dual-trace oscilloscope from DSE Back in September 2005 we reviewed a 10MHz single channel oscilloscope with a small screen, which seemed like a real bargain at $158 from Dick Smith Electronics. Now they have done it again with an even more attractive 20MHz dual trace scope from the same Taiwanese manufacturer. Whereas the single channel scope had a small screen (graticule 48 x 60mm), this new scope is a full-size model with a screen size of 8 x 10cm. Its overall dimensions are 325mm wide, 130mm high and 440mm deep, not including the large tilting bail handle. It has a large number of switches and knobs spread across the front panel, as is usual with any dual trace oscilloscope. Dominating the panel are the vertical input attenuators, which each consist of a variable potentiometer (knob) combined with a concentric 10-position switch giving an input sensitivity from 5mV to 5V/div in a 1-2-5 sequence. Pulling out the knob switches in a gain of 5 so that the maximum input sensitivity is 1mV/div. The screen graticule is eight divisions (div) high by 10 divisions wide, with each division being almost exactly 10mm. Associated with each vertical input attenuator is a 3-position input coupling switch giving AC or DC coupling or grounding the input (just the vertical amplifier input; not the signal lead). Between the two attenuators is 4-position switch which selects channel 1 or channel 2, both channels or adds the two inputs together. Pulling out the Channel 2 trace position knob inverts the signal, so that it is possible to display a single trace for the difference between the two input modes. This is quite handy if you want to set the scope up to display a differential (difference) signal. Just to clarify a point there: unlike some digital scopes, this analog instrument can only ever display two signal traces at a time. Over on the righthand side of the control panel is the 23-position timebase switch, giving a range of timebase speeds from 2 secs/div up to 0.1ms/div. There is also a variable timebase knob and a horizontal trace control, which when pulled, increases the horizontal amplifier gain by a factor of 10. In the triggering section of the panel are two knobs for trigger level and variable holdoff. The trigger level knob can be pulled out to provide negative slope triggering in addition to the normal positive slope triggering. As well, there are two 4-position switches for trigger source (Ch1, Ch2, Line and EXTernal) and trigger coupling. The latter has four modes: Auto, NORMal, TV-V and TV.H. SILICON CHIP WebLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK We supply Radiometrix VHF & UHF OEM radio SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK modules for wireless data comms, control and Our isSC updated daily, over SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SCwebsite WEBLINK WEBLINK SCwith WEBLINK monitoring. 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Contact Phil Benedictus or Lawrence Smith on (02) 9211 9792 for all the details! 62  S C RF Modules Australia JAYCAR JAYCAR ELECTRONICS ELECTRONICS WebLINK: www.rfmodules.com.au WebLINK: WebLINK: www.jaycar.com.au www.jaycar.com.au siliconchip.com.au SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC The TV modes involve and internal TV sync separator. Finally, there are two knobs for trace intensity and focus, and an adjacent screwdriver adjustment to level the trace if that is necessary. All up, the front panel controls are well laid out, clearly labeled and easy to use. Inside, the circuit boards are wellmade and neatly laid and there does not appear to be a surface-mount device anywhere in sight. That and the fact that all the components appear to be commonly available parts, means that the oscilloscope should be straightforward to repair, if that ever becomes necessary. A good instruction manual is provided. The scope comes with two good quality divider probes, switchable between 1:1 and 10:1, a very worthwhile bonus, given the low purchase price of this unit. Overall calibration was good and we found that it had a usable response and triggering up to around 28MHz, making it a very useful instrument. Coupled with the fact that two probes are included in the price of $399 including GST, this dual trace 20MHz oscilloscope is a real bargain. Its catalog number is Q-1802. (L.D.S) Contact: AUDIO MODULES broadcast quality Manufactured in Australia Dick Smith Electronics (all stores) PO Box 500, Regents Park DC NSW 2143. Tel: 1300 366 644 Fax: (02) 9642 9155 Website: www.dse.com.au Harbuch Electronics Pty Ltd 9/40 Leighton Pl. HORNSBY 2077 Ph (02) 9476-5854 Fx (02) 9476-3231 Tiny USB Data Aquisition Module Hytek Automation’s new USB based data acquisition module, the iUSBDaq measures only 90x 85x 30 mm and features: • sUSB 2.0/1.1 full speed interface • USB bus powered • 8 single-ended, 12-bit analog inputs • 0–4.096V analog input range • Up to 32ksamples/sec throughput with single channel; up to 13ksamples/second for streaming mode • Supports both scan mode and continuous streaming mode data acquisition • One dedicated trigger line for streaming mode data acquisition • Two programmable 10-bit PWM outputs (3kHz–333kHz) • 16 bi-directional digital I/O lines (125HZ update rate) • One 16-bit counter • 240 bytes EEPROM reserved for user data • Multiple iUSBDAQs can be connected on same computer • Simultaneous streaming from multiple iUSBDAQs possible • All I/O connections via screw terminals • Works with Windows 98SE, ME, 2000, or XP Software includes • FREE device driver, programming API (DLL), LabVIEW drivers, examples • FREE standalone ready-to-run iDAQTest&Log software for testing, data logging, data playback and simple analysis • 30-day money-back guarantee, six month warranty Extremely easy to use, iUSBDaq’s are being used for research, monitoring and control purposes in private companies and public organisations, universities and colleges around the world. They are priced at $145.00 +GST. Contact: Ocean Controls 4 Ferguson Dr, Balnarring Vic 3926 Tel: 03 5983 1163 Fax: 0011 1 609 895 7447 Website: www.oceancontrols.com.au C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK For everything in radio control for aircraft, JED designs and manufactures a range We specialise in providing a range of C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK model boats and planes, etc. We also carry SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK WEBLINK of single board computers (based on Low Power Radio solutions for SC OEM’s to SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK an extensive range of model flight control Wilke Tiger and Atmel AVR), as well as incorporate in their wireless technology SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK modules SC including GPS, altitude and LCD displays and SC analog and digital I/O basedSCproducts. innovative C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK WEBLINK SC WEBLINK SC speed, WEBLINK SC WEBLINK SC WEBLINK WEBLINK SC WEBLINK SC WEBLINK WEBLINKThe SC WEBLINK SCrange WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SCautopilot WEBLINKand SC WEBLINK SC WEBLINK SC WEBLINK WEBLINK SC WEBLINK WEBLINK WEBLINK SC WEBLINK SC WEBLINK interfaces, groundstation for PCsSCand controllers. JED alsoSCmakes a SC WEBLINK includesSC products from MK Consultants, the SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK controllers. More info on our website! PC PROM programmer and RS232/RS485 world-renowned specialist manufacturer. C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK converters. C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK Tel:(07) 4639 1100 Fax: (07)4639 1275 Tel:(07)SC4934 0413SCFax: (07) 4934 0311 SC WEBLINK Tel/Fax: (02) 3517 C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC9533 WEBLINK SC WEBLINK SC WEBLINK WEBLINK WEBLINK SC WEBLINK WEBLINK WEBLINK SC WEBLINK Tel: (03)SC 9762 3588SCFax: (03) 9762 5499 SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK arch C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK C WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK SC WEBLINK siliconchip.com.au Silvertone Silvertone Electronics Electronics Jed Microprocessors Pty Ltd TeleLink Communications WebLINK: www.silvertone.com.au WebLINK: silvertone.com.au WebLINK: jedmicro.com.au WebLINK: telelink.com.au M 2006  63 SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC SC The prototype SocketBoard is shown here connected to a genuine Atmel AVR ISP programmer. It also works with the AVR in-system programmers described in SILICON CHIP in October 2001 & 2002. AVR ISP SocketBoard Teamed with an AVR in-system programmer, this board enables you to program Atmel microcontrollers on the spot – without an expensive production programmer or development system. It supports just about all dual-in-line AVR micros and includes overcurrent protection. M OST ATMEL AVR microcontrollers can be programmed via their in-built serial programming interfaces (SPI). This method is ideal for in-situ programming, such as might be used in manufacturing or for firmware development or field upgrades. In this scenario, the micro remains in its socket on the application board and a low-cost in-system programmer (ISP) is plugged into a dedicated programming header. In other words, the microcontroller does not have to be removed from its socket and plugged into a parallel programmer each time a firmware update is required. However, in some cases it is desira64  Silicon Chip ble to program a microcontroller standalone, such as when the application board is unavailable or doesn’t include an ISP (or JTAG) header. A low-cost method of stand-alone programming might also be useful where a batch of chips is needed for a small prototype run and the cost of a commercial parallel programmer is prohibitive. This is where the AVR ISP SocketBoard comes in. It provides the minimum of functions necessary to support in-system programming, including a regulated power supply, clock source and microcontroller IC socket. Just connect your in-system programmer to a PC, plug its ISP cable into the By PETER SMITH SocketBoard’s on-board header and add a DC plugpack. You’re then ready to start programming! Programming sockets As you can see from the photos, the SocketBoard contains five programming sockets. Why so many? Well, we’ve provided one programming socket for each group of micros with common SPI pinouts. This allowed us to eliminate the switching logic that would have been required if we’d used just a single, 40-pin socket, so greatly simplifying design and construction. We expect that many constructors will install just one or two programming sockets (depending on their requirements), to keep costs as low as possible. The overlay diagram (Fig.2) lists specific device types and the sockets (SK1-SK5) that support them. For example, to program the ATMega16, socket SK4 must be installed. For cases where quantities of chips need to be programmed, the board will accept standard zero insertion force (ZIF) sockets as well. There is absolutely no need to install ZIF siliconchip.com.au Fig.1: the SocketBoard consists of a current-limited power supply, oscillator, ISP header and a series of programming sockets. This simple configuration supports most dual-in-line packaged AVR micros. Surface-mounted equivalents can be accommodated by using commercial DIL adapters. sockets (as shown in our photos) for occasional programming; this would simply be expensive overkill. The unit can be powered from a 12V DC 150mA (or higher) unregulated plugpack, which also powers the ISP programmer when it’s plugged into the on-board header. Operation As mentioned, the SocketBoard provides the minimum of functions necessary to support in-system prosiliconchip.com.au gramming. As stated, this includes a series of programming sockets to accommodate the different types of AVR micros, a regulated power supply, and a clock source. The power supply is based around two series-connected LM317 adjustable positive regulators (see Fig.1). The first regulator acts as a current limiter. In normal operation, it performs no function. However, should the current through R1 increase to a level where about 1.25V is dropped across it, REG1 begins to reduce the voltage at its OUT terminal. In effect, REG1 then acts as a constant current source, limiting output current to a maximum of 125mA. In normal operation, the complete setup consumes an average of about 20-40mA, depending on the type of in-system programmer connected. The remaining capacity (85-105mA) leaves a comfortable margin, which in most cases is still low enough to preserve any micro that might be accidentally reversed in a socket. It also protects other components if an internally short-circuited micro is plugged into a socket. The second regulator (REG2) is March 2006  65 Fig.2: follow this diagram closely during assembly. Take particular care with the orientation of the electrolytic capacitors, D1, LED1 and IC1. Also, be sure to install the 10-pin header (CON2) with the keyway facing towards the programming sockets. Note that although we show ZIF sockets in five positions, most constructors will require only one or two for high-volume programming. Fig.3: the full-size etching pattern for the PC board. It can also be downloaded from the SILICON CHIP website. 66  Silicon Chip siliconchip.com.au Suitable Programmers This project has been tested with three programmer variants, as follows: • SILICON CHIP In-System Programming Adapter, as described in the October 2001 issue. This very low cost programmer connects to your PC’s parallel port. It’s still available in kit form from Altronics (Cat. K-2885). • SILICON CHIP AVR ISP Serial Programmer, as described in the October 2002 issue. For greater compatibility, this programmer connects to your PC’s serial port. It’s available as a kit from Jaycar Electronics (Cat. KC-5340). • AVR ISP Programmer. This genuine Atmel item is supplied preassembled and again, it connects to your PC via a free serial port.You can purchase these from JED Microprocessors, phone (03) 9762 3588 or browse to www.jedmicro.com.au This is the completed prototype. Make sure that all parts are correctly oriented. configured as a conventional voltage regulator. Without JP1 installed, it produces +5V to power the system. Installing JP1 reduces this to +3V. Some constructors may find this lower voltage useful for verifying the memory in micros that are destined for 3V systems. Note, however, that the two SILICON CHIP in-system programmers are not designed for operation at 3V; you’ll need the genuine Atmel programmer for that job. As well as power, AVR micros require a clock source for their internal programming circuits to operate. This is provided by a Pierce oscillator, which is composed of a 4MHz crystal (Y1), two resistors and one gate of a 74HC04 hex inverter (IC1a). A second gate (IC1b) buffers the clock signal before it is applied to all of the programming sockets. A 47W resistor provides series termination and current limiting. All that now remains to be described is the ISP interface. This is extremely simple indeed, as it consists only of a 10-pin DIL header (CON2) and five resistors. The four 100W series resistors act as peak current limiters, in case the ISP cable or a chip is accidentally inserted with power applied. These also help to protect the programmer if a faulty micro is inserted in a socket. The remaining resistor (47kW) pulls siliconchip.com.au down the interface’s RESET line, so that the micro is held in the reset state if a programmer is not connected or is non-functional. Assembly Using the overlay diagram (Fig.2) as a guide, install all the low-profile components first, starting with the wire links and resistors. There are seven links in total, all of which can be fashioned from 0.7mm tinned copper wire or similar. Follow with all of the capacitors, noting that the leads of the 10mF and 100mF units must be bent at right angles before installation. Before bending the leads, check that you have the positive leads oriented correctly. The crystal (Y1) also mounts horiz­ ontally, so bend its leads about 2-3mm from the can before installation. Once in place, a short length of tinned copper wire should be soldered to the top of the can and the pad directly below to secure it in position. Diode D1, LED1, header CON2 and the 14-pin socket for IC1 can now go in. All of these items are polarised, so make sure that they’re installed the right way around. Don’t plug the 74HC04 into its socket just yet, though; it’s a good idea to test the power supply first (see below). All of the remaining items can now be installed, leaving the five programming sockets (SK1–SK5) until last. The two LM317 regulators (REG1 & REG2) should be attached to the PC board using M3 x 6mm screws, nuts and flat washers. As shown, their leads must be bent at right angles before installation. Be sure to tighten the screw & nut before soldering the leads, otherwise damage to the regulator package or PC board may result. The three 2-pin headers (JP1-JP3) can be cut down from a longer section using a sharp knife. Check that each header is sitting square on the PC board surface before soldering. Finally, install just the programming sockets (SK1-SK5) that you require. For casual use, low-cost IC sockets can be installed in any or all of the indicated positions. Alternatively, ZIF type sockets can be fitted to any positions that are expected to be high usage – it’s up to you. Testing Connect a 12V DC source to the DC socket (CON1), noting that the centre pin is the positive input. If the power connections are accidentally reversed, nothing bad will happen as a series diode provides polarity protection. Now apply power by sliding S1’s March 2006  67 Par t s Lis t 1 PC board coded 07103061, 145 x 105mm 1 4MHz crystal (HC49 package) (Y1) 1 DPDT PC-mount slide switch (S1) (Altronics S-2060, Jaycar SS-0823) 1 10-pin dual-row shrouded (boxed) PC-mount header 1 2.1mm PC-mount DC socket (CON1) 2 20-pin IC sockets (SK1 & SK2) 1 28-pin IC socket (SK3) 2 40-pin IC sockets (SK4 & SK5) 1 6-pin 2.54mm (0.1-inch) SIL header strip (for J1-J3) 3 jumper shunts 6 M3 x 6mm pan head screws 2 M3 x 6mm nuts & washers 4 M3 x 10mm tapped spacers 160mm (approx.) 0.7mm tinned copper wire (for links) Note 1: if desired, small stick-on feet can be used in place of the tapped spacers. Semiconductors 1 74HC04 hex inverter (IC1) 2 LM317T adjustable voltage regulators (REG1 & REG2) 1 1N4004 diode (D1) 1 3mm high-brightness red LED (LED1) Capacitors 1 100mF 25V PC electrolytic 1 10mF 16V PC electrolytic 1 220nF 50V MKT polyester 5 100nF 50V monolithic (multilayer) ceramic 2 22pF 50V ceramic disc Resistors (0.25W, 1% metal film) 1 1MW 1 300W 1 47kW 1 120W 1 1.8kW 4 100W 1 1kW 1 47W 1 360W 1 10W Note 2: low-cost ZIF sockets in all of the designated sizes are available from www.futurlec.com. Higher quality units of various types are available from www.dontronics. com and www.rockby.com.au actuator towards the edge of the board. The power LED should light immediately. If it doesn’t, either the power connections are reversed or there is an assembly error. Carefully recheck the 68  Silicon Chip 8-pin devices are programmed in the first 20-pin socket (SK1). Here’s how they’re inserted, with pin 1 in the same position as for 20-pin devices. Note that jumper shunts must be installed on JP2 & JP3 when programming 8-pin devices. board against the overlay diagram and look for dry or missed solder joints. Next, use your multimeter to measure the voltage between pins 7 & 14 of IC1’s socket. Expect a reading of 5V ±5%. Temporarily insert a jumper shunt on JP1 and measure the voltage again. This time, you should get the lower reading of 3V ±5%. When done, remove the jumper, as in the majority of applications, a 5V supply is preferred for programming. If the power supply checks out, switch off and insert IC1 into its socket. Naturally, the position of the notched (pin 1) end of this IC must match that of the IC socket. Using it It doesn’t take a lot of grey matter to use the SocketBoard. Simply switch power off, plug your in-system programmer into the AVR ISP connector (CON2), and insert the microcontroller to be programmed into the designated socket. After switching on, the micro can be programmed following the instructions supplied with your ISP. Important: always switch the power off before inserting or removing a microcontroller from its programming socket. Note that 8-pin micros present a special case. Instead of a separate socket, all 8-pin devices are programmed in the first 20-pin socket (SK1). In addition, jumper shunts must be installed on JP2 & JP3 to route signals to the correct places for these diminutive devices. After programming an 8-pin device, the two jumper shunts (JP2 & JP3) should be removed if you also intend to program 20-pin devices in the same socket. This ensures that there is no possibility of damage to the larger devices. If a faulty micro is inserted in a socket or if a working device is inserted backwards, the current-limit function will swing into action. In most cases, the current passed through the part should not be destructive – if the problem is noticed right away and power SC is switched off! Warning! Programming the “reset disable” fuse present on some smaller AVR devices disables the RESET input, with the side effect of preventing further programming via the SPI port. In other words, you’ll no longer be able to use your in-system programmer to erase, read, write or verify the affected part. To restore SPI access, the device must be erased on a parallel programmer, high-voltage serial programmer or JTAG programmer, depending on the device in question. Do not experiment with fuse settings unless you know exactly what they do! siliconchip.com.au SILICON CHIP If you are seeing a blank page here, it is more than likely that it contained advertising which is now out of date and the advertiser has requested that the page be removed to prevent misunderstandings. Please feel free to visit the advertiser’s website: www.microbric.com Giving the Viper some direction in life! – ADDING A LINE TRACKER L ast month, we gave the Microbric Viper some control via infrared; this month we’re giving him some eyes, courtesy of a line tracker module. This allows the Viper to follow a high contrast line (at least 20mm wide). This line can be black on a white surface or it can be the opposite – a white line on a black surface. Contrast can be set to suit the lighting conditions and the blackness or whiteness of the line, relative to its background. We’ll cover this shortly. First, as Mrs Beaton’s cookbook says, you have to catch your hare Line Tracker Expansion Pack. That’s the easy part: just mosey into your nearest Dick Smith Electronics store (or visit them on www.dse. com.au) and part with just $29.98 and you’ll receive a pack just like the photograph at right. Naturally, we are assuming that you have been following this series and have previously purchased and built 70  Silicon Chip the Viper robot. It’s a bit hard to do anything unless you have! In the Line Tracker Expansion Pack you’ll also get instructions on how the modules should be attached to your Viper, so we won’t waste space repeating that here. As you can see, the various modules are prebuilt – that’s one of the biggest features of the Viper: the hard work is all done for you! How it works There are two main modules in the Line Tracker – one has a red LED which shines down onto the surface F A B E D C D C The line tracker expansion module contents, shown here still attached to their carrier, include the LED module(A), the line tracker module (B), two right angle modules (C), two straight modules (D), two strips (3-way, E and 5-way, F), plus packs containing 4 Brics, 6 nuts, 12 screws and 6 spacers. siliconchip.com.au Here’s the LED module (left) and the Line Tracker module (right), both reproduced significantly larger than life size (they’re actually about 20mm high). The object in the centre of the left shot is the red LED; the two lighter objects centre right of the right shot are the phototransistors, which pick up the light through holes in the PC board. The IC right in the middle is the microcontroller while the device at the “pointy” end is another LED, this one to indicate it’s logic state (high or low). under the Viper. The second has phototransistors and a microcontroller – as you might expect, the phototransistors “pick up” light reflected from the surface underneath (range is about 3-12mm) which the microcontroller then analyses. A white surface will reflect a lot of the red light, while a black surface will reflect little, if any. The microcontroller determines from the reflected light (or lack of it) whether the surface underneath is white or black and sends a logic high (5V) or low (0V) to the main onboard controller. This then tells the Viper to maintain its present course or to turn back onto the line if the line has turned away or if the Viper has strayed off the path. As the onboard LED is red, the Viper is “blind” to red surfaces (red surfaces reflect just as much red light as white surfaces do). Hence the need for black and white lines and surfaces (either way around). Here’s how to do it: Using the Microbric screwdriver (supplied with the main kit) place the tip into the hole at the front of the Line Tracker (receiver) module until the front LED flashes. When the front LED stays on, place the Viper on the line you want it to follow, then when the LED goes out, place the module on the surface off the line. The front LED should then quickly flash five times to tell you that you have successfully calibrated the unit. If it flashes slowly five times, calibration has failed and you’ll need to repeat the calibration. The reasons for failed calibration could include too similar shades in your line and background (ie, grey and grey instead of black and white) or perhaps the module is mounted too far away from the line. Remember it has a 3-12mm range. So there you have it: something else to keep you and your Viper amused for another month (at least!). Don’t forget, there is plenty more information available at www.microbric.com.au SC Protection While the markings and construction method of the Viper mean that reverse polarity is unlikely, it is not impossible, so both transmitter and receiver modules have a FET in series with the supply line to protect the components. When the polarity is connected the right way around, the FETs conduct, supplying power to the circuits. (This is an idea that you might like to use in projects – it’s more expensive than a series diode but has less voltage drop). Calibration We mentioned earlier that the Viper Line Tracker can be calibrated to suit the lighting and contrast of your lines. siliconchip.com.au The assembled Microbric Viper with Line Tracker module. The receiver module is mounted in front with the right angle modules alongside. The LED goes underneath, aimed down to provide the red light by which the unit tracks. It looks a bit different to the infrared version above left! March 2006  71 CIRCUIT NOTEBOOK Interesting circuit ideas which we have checked but not built and tested. Contributions from readers are welcome and will be paid for at standard rates. unter Greg H onth’s m is this r of a winne s Test tla Peak A ument Instr Steam & diesel loco sounds This circuit can be programmed to produce simple diesel and steam “chuff” sounds for model railways. While the sound quality is comparatively low and no one will ever be able to say, “ah, that’s an Alco”, it can nevertheless produce a unique sound in a small and very low-cost package. The same basic circuit is used for both sound variants; only the PICAXE program is changed to get the diesel or steam sound. Resistor R1 and the setting of the 10kW pot (VR1) are chosen so that the track voltage at the adc1 input (P1) of the PICAXE microcontroller is at 3.3V Listing 1: SteamSound.bas ' Steam loco sound generator with analogue speed input ' PICAXE-08 symbol speed = b1 symbol ontime = b2 symbol offtime = b3 'input voltage 1-160 count 'length of hiss sound in 12ms periods 'quiet time between hiss in ms nextread: readadc 1,speed if speed < 11 then stopped 'get the speed voltage ' Now do the chuffing! times2: offtime = 254 - speed ontime = 175 - speed ontime = ontime/25 + 5 chuff: sound 2,(255,ontime) pause offtime goto nextread stopped: sound 2,(250,50) goto nextread 72  Silicon Chip 'quiet time between chuffs 'duration of chuff 'or try 253 instead of 255 'stopped = quiet hissing sound ' or try 240, 245 or 249 with maximum loco speed. A typical value for R1 would be 15kW, with VR1 then adjusted to give the desirable “chuff” rate or diesel sound rate with the maximum track voltage to be used. Zener diode ZD1 protects the PICAXE input from inadvertent over-voltage, while the 10mF capacitor acts as a filter for pulse-type controllers. The digitally generated waveform appears on output 2 (P2) of the micro. The signal is then fed directly into an LM386 audio amplifier IC via a 22nF coupling capacitor and a simple volume control pot (VR2). Note that because of its lower frequency, the diesel sound needs to be generated at a higher output power for the same perceived volume level. If more output power is desired, two LM386 ICs can be connected in a bridge configuration, or an LM380 can be used in place of the LM386. Datasheets for both of these devices are available from www. national.com. Simple steam loco sound The first program (see Listing 1) is very simple and only 38 bytes in length. The steam “chuff” is just white noise output from the sound command, which is turned siliconchip.com.au on and off at a rate determined by the voltage on the adc1 input. This generates a very harsh sound with no attack or decay time. The sound can be varied by selecting different values in the sound command. For example, sound 2,(255, time) is very harsh and sound 2,(249, time) is less so. The odd numbers give better sounds than the even numbers. Change the “chuff:” section of the code to experiment. The three lines in the “times2:” section set the length of the chuff and the silent time between chuffs. Many more features can be added to this simple program. For example, you could generate three chuffs of one sound and the fourth of a different one, to simulate a loco with a valve timing problem. To try this, change the “chuff:” section as follows: chuff: sound 2,(255,ontime) pause Offtime sound 2,(255,ontime) pause Offtime sound 2,(255,ontime) pause offtime sound 2,(252,Ontime) pause offtime goto Nextread You could even have a different sound for every cylinder! Try values of 255,253,252,251 in the four sound commands; if you have a 3-cylinder Shay, use six sound commands instead! To add a “panting” sound when stopped to simulate a compressor, try modifying the “stopped: section, as follows: stopped: sound 2,(250,50) pause 20 goto nextread Complicated steam sound Listing 2 shows how to modify the chuff sound as the loco slows down. This is achieved in part by saving the previous speed in the oldspeed variable and by modifying the chuffsound variable in the sound command in line with the deceleration. To avoid instability when the speed is just on the borderline siliconchip.com.au Listing 2: BigSteamSound.bas ' Steam sound generator with analogue speed input ' PICAXE-08 symbol speed = b1 symbol ontime = b2 symbol offtime = b3 symbol chuffsound = b4 symbol oldspeed = b5 symbol speed2 = b7 oldspeed = 0 'input voltage 1-160 count 'length of hiss sound in 12ms periods 'quiet time between hiss in ms 'the number represent the hiss in SOUND command 'usually 255 for loudest hiss. 245 is quiet hiss 'previous speed 'oldspeed+10 - used to stop instability when ' speed is just overlapping two input steps read2: readadc 1,speed speed = speed + 5 if speed < 11 then stopped if oldspeed = 0 and speed > 0 then accel L30: speed2 = oldspeed + 10 L35: if speed >speed2 then accel L40: if speed < oldspeed then slowing goto times2 slowing: oldspeed = speed + 10 chuffsound = 249 goto times2 accel: oldspeed = speed - 10 chuffsound = 255 '+10 necessary 'mute the volume 'loud chuff sound ‘ Now do the chuffing! times2: offtime = 254 - speed ontime = 175 - speed ontime = ontime/25 + 5 if speed < 10 then stopped chuff: sound 2,(chuffsound,ontime) pause offtime goto read2 stopped: if oldspeed > 10 then juststopped sound 2,(249,20) goto read2 juststopped: pause 500 sound 2,(255,200) oldspeed = 0 goto read2 'exhaust brakes sound between two analog values, the speed has to increase by two steps before the louder chuff is turned on again. Code has also been added to generate a hiss when the loco stops, simulating brakes exhaust. Diesel loco sound Listing 3 shows an even more complicated BASIC program, this March 2006  73 Listing 3: DieselSound.bas Listing 3 – DieselSound.bas ' Simple Diesel engine sound ' G. Hunter, Feb 05 ' pin1 (adc1) is speed volts input ' pin2 (out2) is amplifier output. ' b0 is the shift register ' b2 is ADC voltage representing speed ' b3 is timer to determine rate of sound (pause). ' b4 is intermediate value for speed/10 ' w4 (b8 & b9) is random number used to sound horn ‘randomly’ symbol seed = b0 symbol speed = b2 symbol oldspeed = b5 symbol decel = b7 seed=56 start: seed = seed*2 if bit4 <> bit5 then xored low 2 bit0 = 1 goto motspeed xored: high 2 'last speed reading, used to determine if changing '1 = speed falling, 0 = accelerating or constant 'initialize - can be any number except 0 and 255 '53 is slow, 36 is fast, 56 is ‘pulsy’ fast '4,9 are fast, 5 is ‘pulsy’ 'shift left 1 bit 'do an XOR on bits 4 & 5 of seed (b0) 'speaker output 'feedback to R/H bit 'speaker output motspeed: random w4 'for horn readadc 1,speed 'read speed into b2 - 15 steps of ‘speed’ if oldspeed = 0 and speed > 0 then Horn2 horn0: if w4 > 65500 and speed > 11 then horn1 '65500 works every 2mins or so at ' max speed - sometimes get 2 or 3 blasts together if oldspeed > speed then slowing if oldspeed = speed and decel = 1 then slowing 'So must be accelerating or at steady speed but was last accelerating accel: decel = 0 loop: oldspeed = speed b4=speed + 30/31 table: lookup b4,(18,10,7,4,2,1,0),b3 paus: pause b3 goto start horn2: sound 2,(57,50) pause 200 'integer result converts 16 steps of speed to 6 'determine the ‘clocking rate’ 'idle + 6 steps of speed 'only enough memory for 6 steps in lookup table 'starting double horn blast horn1: sound 2,(57,150) oldspeed = speed goto loop slowing: decel = 1 if speed = 0 and oldspeed > 10 then juststopped if speed < 60 then loop b3 = 8 'decelerating at higher speeds gives constant 'fast idle oldspeed = speed goto paus juststopped: pause 500 74  S Chip soundilicon 2,(253,200) goto loop 'exhaust brakes sound - try 249 for a quieter hiss time for generating the diesel loco sounds. It generates a rumbling idle sound, which increases in rate as the speed (adc1 voltage) increases. The horn sounds twice as the loco starts to move away. If the speed is reduced, the sound reverts to the idle sound until the speed increases again. This represents the driver “shutting off” and coasting. However, this feature is disabled for speeds less than about 40% of maximum for better effect during shunting. The horn sounds at random intervals while running – the time interval is dependent on the random number generator and the speed of the loco. Sometimes there will be two or three horn blasts together, again depending on the random number generator. When the loco stops, there is a loud hiss for a few seconds to represent the brake and then the idle sound commences. Generation of the diesel sound works on a similar principle to previously published circuits, in that a shift register is clocked at a speed dependent on the loco speed and the last two bits of the register are XOR’d and fed back to the input. It was found that a 5-bit shift register results in a reasonable sound. This is easy to implement in BASIC, as a left shift of a register is just a multiply by two (called “seed” in the program). The initial value for seed greatly affects the sound – experiment and enjoy! Lookup table The clocking speed is read from a look-up table using the input voltage as an index. Because of memory limitations on the PICAXE-08, there is not enough space to have 16 different clocking rates for the 16 input speeds, so only six steps are used. This doesn’t appear to reduce the effectiveness of the circuit. The horn is simply a single note generated by the sound command; vary it to your liking. If the horn sounds too often, increase the “65500” value in the section labelled “horn0:” Greg Hunter, Loftus, NSW. siliconchip.com.au Long life lamp beacon Fish farm leases in the aquaculture industry sometimes have their borders marked with flashing beacons as a safety measure. The markers are usually set on floats with solar panels and suffer considerable impact from the weather. Before the days of high-brightness LEDs, dual filament lamps were used, the idea being that if the lamp was dimmer than usual, then one filament had probably blown. This would necessitate the unsealing of the lamp casing to replace the bulb, followed by resealing and reinstating the unit. This circuit was developed to extend lamp life and as a bonus, allows changes to the flash pattern. It’s based on three 555 timers. As darkness falls, the resistance of the LDR increases until IC1’s threshold (adjustable via VR1) is reached. Its output (pin 3) then goes high, supplying power to the rest of the circuit; this was done as a power saving measure, as low-power CMOS 7555s were scarce at the time. With power on, IC2 starts oscillating at a frequency determined by trimpot VR2 and the 100mF capacitor, which spans a few seconds to a couple of minutes. When the output of IC2 goes high, it releases the reset pin of IC3. At the same time, IC2s discharge pin goes high, allowing the output of IC3 to go high and begin charging the 100mF capacitor via the 10kW resistor. The gate of Mosfet (Q1) sees the slowly rising voltage across the 100mF capacitor and once its gatesource threshold voltage is exceeded (about 2.9V), it begins to conduct. Q1’s effective drain-source resistance therefore decreases gradually with the rise in capacitor voltage, so “soft starting” the lamp and extending its life considerably. Concurrently, the 100mF capacitor connected to pins 2 & 6 of IC3 is charging via VR3. Once the threshold voltage is reached, the lamp is switched off with the aid of IC3’s discharge pin, which rapidly discharges the 100mF capacitor on the gate of Q1. After the light level and time on and off periods are set, the whole assembly can be potted, ensuring that the LDR window is not obscured. Using this setup increased lamp life from weeks to several months and in one case, to five years. Gary Smith, Montrose, Tasmania. ($35) Contribute And Choose Your Prize As you can see, we pay good money for each of the “Circuit Notebook” items published in SILICON CHIP. But now there are four more reasons to send in your circuit idea. Each month, the best contribution published will entitle the author to choose the prize: an LCR40 LCR meter, a DCA55 Semiconductor Component Analyser, an ESR60 Equivalent Series Resistance Analyser or an SCR100 Thyristor & Triac Analyser, with the compliments siliconchip.com.au of Peak Electronic Design Ltd www. peakelec.co.uk So now you have even more reasons to send that brilliant circuit in. Send it to SILICON CHIP and you could be a winner. You can either email your idea to silicon<at>siliconchip.com.au or post it to PO Box 139, Collaroy, NSW 2097. March 2006  75 Circuit Notebook – Continued Accurate milliohm meter Using a few common parts, this simple circuit enables you to measure ammeter shunts, transformer windings and switch contacts, all of which are typically too low in resistance to be measured by most multimeters. To measure the unknown resistance, a constant 100mA of current is passed through it and the resultant voltage drop measured with a voltmeter. An LM317 adjustable voltage regulator forms the basis of the current source, while a 0-200mV digital panel meter (DPM) is used to measure the voltage drop. Using the circuit values shown, DPM readings translate directly to ohms. Calibration is simply a matter of selecting the 2W range, connecting a precision 1W resistor across the “Rx” terminals and adjusting VR1 for a reading of 1.000 on the DPM. The “precision” resistor can be an average value part selected from a range of 1% tolerance parts. Next, switch to the 20W range and using a 10W resistor (selected as before), adjust VR2 for a reading of 10.00. After calibration, it’s possible to measure resistances from less than 10mW to more than 19W with accuracies of better than ±5mW (typically ±2mW) on the 2W range and ±50mW (typically ±20mW) on the 20W range. If the device to be measured cannot be connected directly across the “Rx” terminals, then a 4-wire measurement technique can be used instead. To do this, first disconnect the DPM from the “Rx” terminals with switch S1. The “Rx” and “M” terminals can then be individually connected across the device to be measured using two pairs of flying leads or probes. Power can be provided by two small 9V batteries. If the DPM requires a 5V supply, then this can be accommodated with the addition of a 78L05 voltage regulator. Alternatively, a rectified and filtered supply based on a 2VA transformer with dual 6V secondaries could be used to provide mains operation. Either way it should be possible to fit all of the components into a small instrument case. Hugh Middleton, Maungaraki, NZ. ($35) Sensitive over-current protector The Portable PIC Programmer (SILICON CHIP, Sept. 2003) made use of the shutdown pin of an LP2951 voltage regulator to limit supply current. A similar current limiting function can be added to 3-terminal regulator circuits that do not have a shutdown pin by adding a P-channel MOSFET, as shown here. The gate of the MOSFET is driven from the current mirror circuit described in the original article. With the component values shown, output current is 76  Silicon Chip limited to around 100mA. To ensure continued operation at low supply voltages, a logic-level MOSFET such as the 2SJ538 should be used (available from www.farnellinone.com.au, Cat. 476-1108). Keith Gooley, VK5OQ, One Tree Hill, SA. ($35) siliconchip.com.au Delay circuit for power windows If you’ve fitted after-market power windows to your vehicle, then you’ll appreciate this circuit. It allows you to wind up your windows for a period of about 30 seconds after the ignition has been switched off – a common feature on many late-model vehicles! The first 555 timer (IC1) is wired as an astable multivibrator, with an oscillation frequency of around 1kHz. The reset input for this IC (pin 4) is connected to the ignition circuit, so that it will oscillate while the ignition is switched on. IC2 is wired as a monostable multivibrator with a timing period of about 30s. A low pulse from IC1’s output triggers IC2, starting the timer. If the ignition is switched on, IC1 will be free running, so a positive pulse will shortly follow, causing Q1 to conduct and immediately discharge the 100mF timing capacitor. This resets IC2’s timing period and the cycle repeats. During this time, IC2’s output (pin 3) is high, energising relay RLY1 to provide +12V to the power window circuits. In fact, IC2’s output can never go low while IC1 is oscillating and the ignition is switched on. However, once the ignition is switched off, IC1’s reset input is pulled low via a 1kW resistor and it stops oscillating. This in turn means that IC2’s timing capacitor no longer gets discharged, allowing it to time out after 30s. The output then goes low, removing power from the relay and consequently disabling the power window circuits. A diode (D1) across the relay coil protects the 555’s output from induced spikes, while zener diodes ZD1 & ZD2 and series resistors at the two inputs protect the circuit from high-voltage transients. Rod Smith, Bendigo, Vic. ($40) The Latest From SILICON CHIP NOT A REPRINT! Completely NEW projects – the result of two years research & development • Learn how engine management systems work 160 PAGES 23 CHAPTE RS Fro m the pu bli sh ers of • Build projects to control nitrous, fuel injection and turbo boost systems • Switch devices on and off on the basis of signal frequency, temperature and voltage • Build test instruments to check fuel injector duty cycle, fuel mixture and brake and coolant temperatures Mail order prices: Aust. $A22.50 (incl. GST & P&P); Overseas $A26.00 via airmail. Order by phoning (02) 9979 5644 & quoting your credit card number; or fax the details to (02) 9979 6503; or mail your order with cheque or credit card details to Silicon Chip Publications, PO Box 139, Collaroy, NSW 2097. siliconchip.com.au Intelligen t turbo timer I SBN 095 852 9 7809 5 294 - 4 8 522 94 $19.80 (inc GST) B & nitrous OOST fuel cont rollers 6 NZ $22.00 (inc TURBO GST) How eng in managem e ent works March 2006  77 Circuit Notebook – Continued Versatile electronic load When you need to measure the performance of power supplies and DC-DC converters, an adjustable electronic load can be worth its weight in gold. The trouble is that commercial electronic loads are almost that expensive! Here’s a circuit for a flexible little unit that can be adjusted to draw almost any desired current up to a maximum of 6A, from DC voltage sources of up to 450V and with a peak power dissipation of 120W. The adjustable load itself is form­ed by Q1, an STP6NK60Z (or MTP­ 6N60E) power MOSFET in a TO-220 plastic package. This device has a 78  Silicon Chip maximum drain-source voltage of 600V and a maximum drain current of 6A. In this application, it’s mounted on a Jaycar HH-8526 heatsink and cooled by a 40mm 12V fan (Jaycar XC-5054), to allow it to cope with the power dissipation. MOSFET Q1 is connected in a standard “constant current” circuit, allowing its current to be easily adjusted. One of three known resistance values is connected between its source and the negative input terminal (also circuit ground), while op amp IC1b compares the voltage across the source resistance (directly proportional to MOSFET current) and a reference voltage adjustable between 0V and +9V via potentiometer VR1. The output of IC1b is used to provide the forward gate bias for Q1, so the drain-source current of Q1 becomes easily set by adjusting VR1. Switch S1 is used to select the value of source resistance for Q1 and hence forms a current range selector. In the first position, the effect­ ive source resistance is 100W, which allows very low current levels to be set; in the second position, the resistance drops to 10W, for higher current levels; and in the third position, the resistance drops to 1.0W, for setting the highest current levels. Note that as there is a significant amount of power dissipated in the source resistors at higher current levels, these three effective resistance values are made up using multiple siliconchip.com.au Select your microcontroller kit and get started... Right: the MOSFET should not be operated outside its safe operating area (SOA), as depicted in this graph. It’s a good idea to attach a copy of this to the top of your load box for easy reference. From $295* RCM3400 Fax a copy of this ad and receive a 5% discount on your order! Feature rich, compiler, editor & debugger with royalty free TCP/IP stack • Prices exclude GST and delivery charges. Tel: + 61 2 9906 6988 Fax: + 61 2 9906 7145 www.dominion.net.au 4007 WHERE readily-available power resistors. To make it easy to adjust the current levels, a low-cost digital panel meter (Jaycar QP-5570) is configured as a 0-20V meter, with its inputs connected between the source of Q1 and ground (ie, across the effective source resistance). This means that the meter reads the load current of Q1 directly in milliamps (ranges 1 and 2) or amps (range 3). To control Q1’s heat dissipation, temperature sensor TS1 (an LM335Z) is clamped to the same heatsink as Q1 but on the opposite side. The voltage drop of TS1 is therefore closely proportional to Q1’s operating temperature and this voltage is compared with a reference voltage of +3V by IC1a. As a result, as soon as the temperature of Q1 rises above about 27°C, IC1a turns on the cooling fan via transistor Q2. A simple power supply based on a small 12V/150mA transformer runs all of the above circuitry. Regulators REG1 and REG2 provide +9V and -5V for the op amps, while a separate half-wave rectifier provides +12V for the cooling fan. REG3 provides +5V for the digital panel meter. The prototype was housed in a plastic instrument case measuring 200 x 158 x 64mm (Jaycar HB-5912). The cooling fan was mounted under a 40mm diameter hole cut in the centre of the case lid, with a protective wire grille above it. Most of the circuitry was mounted on a small PC board, fitted in the lower half of the case alongside the power transformer. The transformer itself was mountsiliconchip.com.au ed on an earthed metal plate for rigidity. An ML-97 type heatsink was used for Q1, positioned just to the left of the centre of the PC board, so that it is directly under the cooling fan when the case is assembled. Extra 8mm diameter holes were drilled/ reamed along both sides of the lower case half to provide exit points for the cooling air. The maximum instantaneous cur­ rent that can be sunk by the load varies with applied voltage. This limitation is imposed by the MOSFET’s safe operating area (SOA), as depicted in the accompanying graph. It’s a good idea to attach a copy of this to the top of your load box for easy reference. Incidentally, a PC board is avail­ able for this design – phone RCS Radio on (02) 9738 0330 and quote code number 04112051 (ELECLOAD) to order yours. In addition, the board pattern and overlay diagram can be downloaded from the SILICON CHIP website. The STP6NK60Z MOSFET is available from www.farnellinone. com.au, Cat. 483-3521. Editor’s note: maximum contin­ uous power dissipation for the MOSFET will be approx. 15-20W, assuming a heatsink temperature rise of 65°C above ambient and with fan-forced cooling. The 120W value referred to is theoretical and assumes an infinite heatsink. However, the load will undoubtedly handle considerably more than 20W for short, intermittent periods. Jim Rowe, SILICON CHIP. can you buy SILICON CHIP You can get your copy of SILICON CHIP every month from your newsagent: in most it’s on sale on the last Wednesday of the month prior to cover date. You can ask your newsagent to reserve your copy for you. If they do not have SILICON CHIP or it has run out, ask them to contact Network Distribution Company in your state. SILICON CHIP is also on sale in all stores . . . again, you can ask the store manager to reserve a copy for you. Or, to be sure that you never miss an issue and save money into the bargain, why not take out a subscription? The annual cost is just $83 within Australia or $89 (by airmail) to New Zealand. Subscribers also get further discounts on books, and other products we sell. A NOTE TO SILICON CHIP SUBSCRIBERS Your magazine address sheet shows when your current subscription expires. Check it out to see how many you still have. If your magazine has not turned up by the first week of the month, contact us at silchip<at>siliconchip.com.au March 2006  79 SALVAGE ENGINEERING “The whole may be less valuable than the sum of the parts” I f any single item has come to represent the cost-effective “state of the art” in modern consumer electronic devices, it surely must be the ubiquitous solar garden lamp. Selling for around $50 when first introduced in the mid 90s, the early models earnt bad press due to their inefficient and short lived filament lamp. Their panel placement (flat on top) was also a design flaw for non- tropical latitudes, where the sun is at a lower angle even in summer. Slanted panels will better pick up such valuable sunlight and allow dirt, leaves and even snow to slide off as well. LED replacement using the colours of the era (red, amber and green) of course gave unrealistic night lighting. Although red is well known for preserving one’s night vision, that colour rather implies leading the wayward rather too encouragingly up (or down?) the garden path as well... It wasn’t until the early 2000 ultrabright white LED breakthrough that normal white lighting became possible – but at a price! Those first white LEDs were around $10 each and although now much cheaper, they still fetch a premium over other colours. They also demand 3.6V rather than the 1.82V of normal LEDs, meaning mutiple cell batteries (typically 3 x 1.2V NiCd/ NiMH ) would be needed. Since each solar cell photovoltaic (PV) wafer typically produces 0.5V this implies a more costly 8-segment (4V) PV as well. by Stan Swan* 80  Silicon Chip Those solar garden lights can often be bought for next to nothing but reveal a treasure-trove of electronic goodies just waiting for the experimenter . . . siliconchip.com.au X Here’s one of the older-style “ordinary” component controllers from a bargain store solar lamp. How can they possibly make these for the price? So because they’re now efficient and reliable and allow easy DIY lighting but have more costly components, one would expect 2006 solar powered garden lamps to be still around the original $50 mark; not on your life! Old hands don’t know whether to laugh or cry, as hardware, chain and bargain stores worldwide now have shelves stashed to the rafters with bargain solar garden lamps at prices well under $5. Even that may be laughable, since bulk buying can land you a 10-pack for as little as $2 each here in NZ. You could hardly fold up and ship their cardboard box for that sum and most Chinese students here consider them At the bottom is one of the newer SMD controllers. If you want continuous operation (ie, not turning off at dawn) cut the PC board track where shown with the red “X”. grossly under-priced – “Even in China they’d cost more than that”! Sadly such throwaway prices imply electronic junk, only serving to persuade many youngsters that electronic careers have no money in them. Well – you can hardly blame them. With many sparkies often now earning executive incomes and boring mains electrical hardware costing an arm and a leg, “bright sparks” may feel they’d be better off working with copper instead of silicon. Rather than such gloomy navel gazing however, let’s turn the approach around and think positively. Interestingly, the present lamp models being sold add value externally rather than with the light itself. Instead of UV-prone plastic, pricier models increasingly offer sturdy stainless steel poles and mount brackets and classier designs that better integrate into gardens. Hands up all those who want a A$100 solar powered cane toad-style light at their front gate! Forgoing such whims and focusing on the internals reveals most of the models examined here had very similar hand-assembled electronic internals, although a more recent trend towards “pick and place” surface mount devices (SMD) seems apparent. Aha – a cheap source of SMD parts for you to practice on? Many full descriptions of the simple Solar Lamp salvaged parts with approx value if purchased new * Rugged business card sized, epoxy embedded, 4-segment 2V at ~30mA solar panel. Usually hot melt secured but easily detaches with a heat gun. Can be carefully drilled for more convenient mounting Say $5 – perhaps vertically for valuable low-angle winter sun. * 1.2V, 600mAh rechargeable Nicad cell. Although these are now inferior to much higher capacity (and $1 less harmful) NiMH versions, they are still considered ideal for powerful work and multiple charges. 50c * Single AA battery holder – easily separates with snips from plastic mount. * Schottky diode (typically a 1N5819) – valuable for its lower voltage drop (~200mV) than ordinary silicon 50c diodes and just the sort of item you never have on hand when needed. $1 * Ultra-bright white LED – may be only a “cooking version” but usually 5000mCd. $1 * Switch – suitable for school project DC work. $1 * Precision inductors – typically 470mH (microhenry) range, handy for AC theory, RF and calibration work. ~ 50c * BC547 style transistors – with tiny “hard to buy” SMD types now showing up. 20c * Assorted resistors, capacitors and screws. 10c * Assorted short lengths of coloured wire. Priceless! * Clear plastic dome – to keep snails from your garden seedlings etc. * Assorted sectioned plastic support tubes – donate to your local kindy perhaps? * Clear plastic Total Internal Reflection (TIR) optical guides – handy for physics? * Cardboard box – corner reflector 2.4GHz antenna when foil covered (a ZigBee antenna article follows soon!). siliconchip.com.au March 2006  81 Just how efficient are they? Removing the white LED and replacing it with a 1N4148 type diode fed to a ~470mF electrolytic capacitor will make a convenient low current, voltage boosted half-wave rectifier DC supply. Test loading gave the following values (in all cases just from a single AA Nicad power source): Vin I in ~Pin Vout I Out ~P out ~efficiency V mA mW V mA mW % 1.2 17 20 2 5.5 11 55% 1.2 12 14 3 3.1 9 64% 1.2 6 7 4 1.2 5 71% 1.2 4 5 5 0.4 2 40% 1.2 3 4 6 0.2 1.2 30% 1.2 3 4 7 0.15 1.0 25% 1.2 3 4 8 0.1 0.8 20% 1.2 3 3 9 0.06 0.5 16% 1.2 3 3 10 0.01 0.1 3% 1.2 3 3 11 0 To run the inverter continuously (when it takes ~3mA at idle), or at least run it as needed to top up a supply capacitor, you remove the PV sensing point from the pc board. Just lift the PV red wire and Schottky diode off the board and solder them directly together. This now gives a full-time solar top-up/powered circuit, with a typical charge rate of ~12mA into the Nicad cell in mid day overcast. Although the supply output may be rough to our Picaxe, an extended run with both an 08M and 433MHz transmitter powered across the 470mF capacitor was faultless. but sophisticated circuitry are on line, with Australian Colin Mitchell’s site at www.talkingelectronics.com.au/ Projects/SolarLight/SolarLight.html particularly lucid. Typically, the single 1.2V AA Nicad inside is trickle charged from the 2V solar panel. In full sunlight the panel output is about 30mA – about twice the night time current demand of ~12-15mA. This nicely means five sunshine hours will give some 10 hours of night-time illumination – enough for most needs unless you regularly stagger home from a club at 4AM in winter and drop your house key in the long grass. Only a single 1.2V AA cell? How can that power any LED, let alone a 3.6V white one? The secret is to convert, via a high frequency (~100kHz) transistor oscillator, this low-voltage DC into pulses that’ll briefly flash the LED. Human “persistence of vision” visually smoothes any flashes over say 20Hz, so these spikes give a seemingly steady light output. This is aided by the white LED phosphor “after glow”. The Latest From SILICON CHIP The oscillator is a simple coil and capacitor (LC) type – those fat “resistors” shown in the picture are in fact inductors. The return of daylight stops the oscillation when even a small voltage is again PV generated. Just in time for that elusive house key to glint in the morning sunshine. . . What? You live in the mountains, never go outside at night, have no need for a garden light, or don’t even want to know how they work – but instead just want to – gulp – gut them for parts! It seems a telling statement about today’s electronics but these garden lamps are such a parts goldmine that they’re indeed worth purchasing just to scrap. Additionally, schools’ electronics classes, long taunted with the agony of defeat when circuits fail to work, should perhaps seriously consider them for their motivational benefits. Imagine the kids’ enthusiasm when you start the class with a working device, which is then progressively dismantled into individual parts by the period end, all set for a fresh project next time. A brand new working item, tool use, fiddly parts handling, identification and storage, with more to follow? Yay – this seems very educational indeed and sure beats frog dissection in biology – you can’t re-use frog internals! So there you go – even if you paid $3 each, you’ve more than tripled your initial investment, with over $10 worth of electronic goodies all set for some serious circuitry next month – try doing that with an Ipod. Who said there’s no money in electronics! SC * stan.swan<at>gmail.com 160 PAGES 23 CHAPTE RS Completely NEW projects – the result of two years research & development • Learn how engine management systems work • Build projects to control nitrous, fuel injection and turbo boost systems • Switch devices on and off on the basis of signal frequency, temperature and voltage • Build test instruments to check fuel injector duty cycle, fuel mixtures and brake & temperature Mail order prices: Aust. $A22.50 (incl. GST & P&P); Overseas $A26.00 via airmail. Order by phoning (02) 9979 5644 & quoting your credit card number; or fax the details to (02) 9979 6503; or mail your order with cheque or credit card details to Silicon Chip Publications, PO Box 139, Collaroy, NSW 2097. 82  Silicon Chip From the publishers of Intelligent turbo timer I SBN 095852294 - 4 9 780958 522946 $19.80 (inc GST) NZ $22.00 (inc GST) TURBO BOOST & nitrous fuel controllers How engine management works siliconchip.com.au Custom-made Lithium Ion, NiCd and NiMH battery packs Smart Chargers www.batterybook.com (08) 9240 5000 High-capacity 280mAh rechargeable 9V 2400mAh NiMH AA cells siliconchip.com.au High-quality single cell chargers with independent channels. Charge any combination of NiCd & NiMH AA and AAA cells High-capacity 9Ah rechargeable D March 2006  83 PHONE/FAX MISSED CALL ALERT By JIM ROWE This device detects an incoming call on your phone or fax and lights a LED and latches on a relay, which you can use to switch on a lamp or horn in another room or your garage. S o what’s wrong with listening for the phone ringer or looking at the fax machine’s “out” tray? If you work at home you need to be able to respond to phone calls or faxes as soon as they come in but you cannot be hovering over the phone all day; there are times when you have to leave your office or home and if you do not physically lift the phone handset and listen (if you have Messagebank) or check the fax as soon as you arrive back, calls or faxes could be without a response for some time. Or maybe you have an office but spend some time in the workshop. Same problem – or even more so if you are waiting on an important call or fax. So this is the remedy. Build this device and it will let you know that a phone call has been made or a fax has been received, without you needing to actually check the phone or fax. What’s more, you can use it with a remote light or siren to alert you over the noise of machinery! The Phone/Fax Missed Call Alert hooks up easily to the fax machine’s phone line. It connects in very easily, using a standard low-cost modular cable. The kit of parts should set you back no more than about $30 and you should be able to build it up in a couple of hours at most. How it works When someone dials your phone or fax number, the exchange sends out short (200ms) bursts of a 75V 17Hz AC signal – the ‘ring signal’. It’s this signal that causes your phone to ring or triggers the fax machine into answering and receiving the message. Our Missed Call Alert is designed to monitor the phone line and respond to the same ring signal, using it to trigger a flipflop and hence latch a relay. 84  Silicon Chip As you can see from the circuit diagram, the Missed Call Alert has two standard RJ12 modular phone sockets, interconnected so that it can easily be connected in ‘daisy chain parallel’ (ie, it doesn’t break the circuit) with your phone or fax machine. It connects across the phone line with a simple ‘bridging’ circuit, consisting of a 470nF capacitor and 22kW resistor connected in series, which passes only AC and limits the current, plus a bridge rectifier formed from diodes D1-D4 to convert the 17Hz AC signal into pulsating DC. This small pulsing DC current (about 2mA) is passed through the input diode of the 4N25/28 optocoupler. With each pulse the diode emits IR light, which in turn causes the phototransistor inside the opto to conduct. Zener diode ZD1 is connected across the opto’s diode to protect it from damage in the event of noise ‘spikes’ on the phone line. These can occur, for example, during thunderstorms. Now until this happens, the phototransistor is not conducting and as a result the input of gate IC1a (pin 1) is pulled up to +12V by the 100kW resistor. The 100nF capacitor also charges up to +12V. But when the phototransistor conducts as a result of the ring signal, the 100nF capacitor is discharged and pin 1 of IC1a is pulled down to ground potential. As a result the output of the gate (pin 3) switches high, pulling input pin 13 of gate IC1d high as well. At the same time the 100nF capacitor connected between input pin 12 and ground also begins charging, via the 1MW resistor. If the sensing circuit has detected a true ring signal, the output of IC1a will remain high for about 200ms – the length of the first burst of 17Hz AC. This gives more than enough time for the 100nF capacitor to charge up to logic siliconchip.com.au The circuit monitors the phone line for ring voltage and turns on a LED and the relay. high level via the 1MW resistor and as soon as this happens both inputs of IC1d will be at this level. As a result the output of IC1d (pin 11) will switch low – producing a negative-going pulse to trigger the R-S flipflop formed by interconnected gates IC1b and IC1c. If the sensing circuit has not detected a true ring signal, the output of IC1a will fall low again before the voltage on pin 12 of IC1d has reached logic high level and when it drops it will remove the charge on the 100nF capacitor via diode D7. As a result both inputs of IC1d will return to ground potential and its output will never switch low. So the purpose of D7, the 1M resistor and 100nF capacitor is to ensure that the flipflop is only triggered by a valid burst of ring signal. The flipflop based on IC1b and IC1c is normally in its reset state (output pin 4 high, output pin 10 low), because when 12V power is first applied pin 5 of IC1b is held at logic low level for a couple of milliseconds until the 100nF capacitor connected from this pin to ground has time to charge up via the 100kW resistor. With the flipflop in this reset state, the gate of MOSFET transistor Q1 is held down at ground potential via pin 10 of IC1 and the 100W suppressor resistor. Q1 is therefore held off. But when pin 11 of IC1d drops low as a result of the circuit sensing a valid burst of ring signal and the flipflop is triggered into switching into its set state, this results in pin 10 of IC1c switching high. This switches on Q1, allowing it in turn to activate the relay and LED2, to indicate that a call has been received. It stays this way until you physically reset the Missed Call Alert by pressing pushbutton switch S1 briefly. This discharges the 100nF capacitor, applying a negative-going pulse to the pin 5 input of IC1b until the capacitor recharges siliconchip.com.au NOTE: The Miss ed Call Alert is not ACA App roved All devices desig ned to connect dir ectly to the PSTN (public switched telephone networ k) require official Approval before ACA they may be leg ally connected to Telstra network. the Strictly speaking this requirement also applies to ou Phone/Fax Missed r Call Aler t. Howeve r in designing the we have taken gr unit eat care to ensure that if built up exac as described, the tly Missed Call Aler t may be connected PSTN line with co to a mplete safety. via the 100kW resistor. This brief negative-going pulse switches the flipflop back to its reset state, with pin 10 held at ground potential and Q1 turned off again. Thus the relay is de-activated and LED2 also turns off. Most of the circuit operates from a nominal 12V DC supply, which can come from either a 12V plugpack or a 12V battery. Diode D5 provides protection against reverse polarity damage, while ZD2 ensures that the supply voltage for IC1 can never exceed about 12.5V. LED1 provides power indication. By the way, you can use either a standard 5mm red LED for LED2 or alternatively, one of the types featuring its own built-in flasher. The latter cost about 75 cents more than a standard LED but the flashing feature makes them better at attracting your attention. Whichever type of LED you use, March 2006  85 the relay simply turns on when a call occurs and remains on until you press the reset button. should be hassle-free if you use the overlay diagram and photos as a guide. Begin by fitting the two RJ12 sockets at the left-hand end. No electrical connection Make sure all six of their fine connection wires are passNote that because we’re using an optocoupler to sense ing down freely through the matching board holes before the presence of a ring signal on the phone line and couple you push their plastic mounting spigots through the larger this information to the rest of the circuit, there is no ohmic holes, as the latter tend to ‘snap’ into place and this can connection between the two – or between the phone line buckle any of the fine wires that isn’t free to move. Then and anything connected to the Missed Call Alert via the when both sockets are snapped into position, turn the board plug pack supply or the relay contacts. over and solder all wire leads to their pads. In fact the optocoupler provides a very high degree of Next fit DC connector CON3 to the board, along with isolation: it can withstand voltages of more than 5000V the 3-way terminal block. Then fit the resistors, including peak for over a minute, with an isolation resistance of the larger 22kW 1W unit which fits in the lower left-hand something like 100GW (yes, Gigohms!). corner. So the Missed Call Alert itself is well protected against Follow these with the non-polarised capacitors, noting damage from ‘spikes’ on the phone line, and the phone that the 100nF MKT cap goes just above the vertically line is also protected against anything nasty which might orientated 100W resistor, while the three smaller 100nF somehow find its way into the circuit. multilayer monolithics go in the other positions. Note also that the board has four holes to fit the 470nF capaciConstruction tor in the upper left-hand corner, so you should have no Building the Missed Call Alert is particularly easy, betrouble fitting either a 630V metallised polyester cap or a cause virtually all of the elec250V AC X2 class metallised tronic parts are mounted on a polypropylene. small PC board. This measures Next fit the two electrolytic 122 x 58mm, carries the code caps, taking care to fit both Please note that the Phone/Fax Missed Call Alert is only 12103061 and has rounded with their positive leads suitable for detecting the arrival of calls for a standard cutouts in each corner so that downwards. After these you (‘POTS’) phone or fax machine. it fits easily inside a standard can fit the 1N4004 power It is not suitable for use with fax machines connected to UB3 utility box. It actually diodes D1-D6, which are all Telstra’s FaxStream system, as this uses carrier signals mounts behind the lid of the orientated with their cathode higher in frequency than speech signals and does not use box, via four 25mm long M3 band ends upwards. Then fit a 17Hz ring signal – rather like ADSL data communication. tapped spacers. ZD1, which is orientated the Wiring up the PC board same way, and finally signal It’s not compatible with FaxStream 86  Silicon Chip siliconchip.com.au Construction is really simple because everything mounts on the one PC board. Note the “extensions” to the pushbutton (reset) switch – these are required to bring the switch up to front panel height. The LEDs just poke through the panel. diode D7 and ZD2. The last two are both mounted ‘east-west’, with their cathode bands towards the west (or left). Now fit the ‘active’ semiconductor parts, starting with Opto1 and progressing through IC1 and Q1. Take care when you’re soldering the last two in place, as they’re both CMOS devices and therefore susceptible to static charge damage. Use an earthed soldering iron and ideally, earth yourself as well using a wrist strap. Don’t fit the two LEDs permanently at this stage but just pass the leads of each one through the board holes (longer anode leads uppermost) and just tack-solder the cathode leads to their pads to hold each LED in place. Now fit the relay to the board, soldering all five of its connection pins to the pads underneath. This will make your board assembly ready for fitting to the lid of your box. If you’re building the project from scratch, you’ll now need to drill the various holes in the box lid as shown in the cutting siliconchip.com.au Use the photo above in conjunction with the layout below to assemble the project. March 2006  87 ALL DIMENSIONS IN MM F F F F HOLE A: HOLES B: HOLES C: HOLE D: HOLE E: HOLE F: 12mm diam 5.25mm diam 3.5mm diam, csk 8 X 15mm, rect. 8mm diam Existing You’ll need to drill the UB3 case as shown in these diagrams. The four spacer holes are later hidden by the front panel. diagram. You might also want to cut the holes in the ends of the box itself as well, ready for the final assembly. If you’re building from a kit, this may all have been done for you. Before you fit the PC board assem- bly to the lid, first fit pushbutton S1 through the 12mm diameter hole in the lower centre and gently tighten its large plastic nut underneath using a spanner. Don’t apply too much force, as this will strip the plastic threads. Now turn over the lid, and solder two 20mm lengths of tinned copper wire (or resistor lead offcuts) to the switch connection lugs, to extend them. Next fit the four 25mm long M3 tapped spacers to the rear of the lid, us- Here’s how to connect it to the phone line. At left are shots of the drilled case lid and the completed assembly going into the case. 88  Silicon Chip siliconchip.com.au ing four countersink-head M3 screws and with an M3 flat washer between each spacer and the rear of the lid. The washers are used to extend the lid-PC board spacing to about 25mm, because this is necessary to provide clearance for the relay. Bring the PC board up to the rear of the lid, lining it up carefully so the wires from the lugs of S1 pass through their matching holes in the board and the bodies of the two LEDs pass through their matching holes in the lid. Then with the board resting on the outer ends for the four spacers, fit the four round-head M3 screws to fasten the assembly together. You should now be able to solder the wires from S1 to their surrounding pads on the board. It will probably also be necessary to untack the temporary LED lead joints, to let you extend the LED bodies through their lid holes as far as they’ll go, while leaving enough of the leads on the copper side of the board to allow you to make the final ‘permanent’ solder joints. Your Missed Call Alert will then be fully wired and assembled, and ready to be fitted into the box. It simply slips down into the box vertically, after which you can fit the four box assembly screws and the plastic sealing bungs. Putting it to work There are no setting-up adjustments to be made to the Missed Call Alert, so you should be able to put it to work as soon as it’s finished. Just connect it into the phone line of your phone or fax machine using readily available RJ12-RJ12 modular cables, as shown in the hookup diagram, then supply it with 12V DC power from either a plug pack or a suitable battery. You won’t need a heavy-duty plug pack -- the Call Alart only draws about 36mA in standby mode, or about 80mA when it has registered a call and activated LED2 and the relay. That’s it. You should find that as soon as a call arrives, the Missed Call Alert will light (or flash) LED2 and activate the relay. So if you use Above is the same-size front panel artwork (also useful as a template!) while the PC board pattern is shown below. the relay contacts to control a lamp or siren in another room, they’ll be activated as well. To reiterate, to reset the Missed Call Alert all you have to do is press the reset button which turns off LED2 and the relay, resetting the circuitry to wait for the next call. SC Parts List 1 PC board, code 12103061, 122 x 58mm 1 ABS jiffy box, UB3 size (130 x 67 x 44mm) 1 2.5mm concentric DC connector, PC board mounting (CON3) 2 RJ12 modular phone socket, PC board mtg (CON1,CON2) 1 3-way terminal block, PC board mounting 1 SPDT 10A PC board mounting relay, 12V/200-285W coil 1 SPST momentary pushbutton, panel mounting 4 25mm long M3 tapped spacers 4 M3 flat washers 4 6mm long M3 machine screws, csk head 4 6mm long M3 machine screws, round head Semiconductors 1 4093B quad CMOS Schmitt NAND (IC1) 1 4N25 or 4N28 optocoupler (OPTO1) 1 2N7000 N-channel MOSFET (Q1) 1 3.3V 1W zener diode(ZD1) 1 12V 1W zener diode(ZD2) 1 5mm green LED (LED1) 1 5mm red LED, flashing type if desired (LED2) 6 1N4004 power diode (D1-D6) 1 1N4148 signal diode (D7) Capacitors 1 1000mF 16V RB electrolytic 1 10mF 16V RB electrolytic 1 470nF 630V metallised polyester (or 250V AC Class X2 metallised polypropylene) 3 100nF multilayer monolithic 1 100nF MKT metallised polyester Resistors (0.25W 1% unless specified) 1 1MW 2 100kW 1 22kW 1W carbon composite 2 1.2kW 2 100W siliconchip.com.au March 2006  89 Salvage It! BY JULIAN EDGAR A low-cost large-display anemometer Live in a windy area? Like to have a big dial showing the outside wind speed? Here’s an anemometer that you can build for next to nothing. I F YOU’RE A SAILOR or kite flyer it’s a must to know wind speed; and even if you’re neither of these, it’s fun to watch the display. The measurement range here will depend on how you set it up but typically you’ll be able to read speeds from just a few km/h upwards. Cost? Well, depending on how you source the components, you’re looking at not much at all! And best of all, this is a project that will totally stun your friends or spouse – they will wonder how the hell you made a working instrument from all that junk! The components Hang onto your seat, folks; this project is for “Serious Ratters” only. Why? Well to make this design, you’ll need a whole bunch of stuff but most will be able to be picked up for next-to-nothing at a few garage sales. Alternatively, it’s a project to keep in mind as you collect bits and pieces over a period. First up, you’ll need the video head assembly from a VHS video cassette recorder. The bearings have to be in good nick, so before removing the head from the VCR, give it a spin while listening closely. The vast majority will Fig.1: the anemometer uses the internals of a discarded mouse to generate a frequency output proportional to wind speed. This signal is fed into an amplifier (salvaged from a cassette player) which feeds a charge pump circuit made from a handfull of passive components. The resulting voltage is displayed on the speedo. 90  Silicon Chip Fig.2: the mouse plug pin-outs. You can easily find the pinouts for other mouse plugs by doing a web search for “mouse pinouts”. In this application, we use only +5V and ground (earth) connections. siliconchip.com.au A video head salvaged from an old VHS VCR provides the bearings, mounts and precision shaft for the anemometer. The complete VCR cost just $1.00. spin superbly – they have really good bearings – but occasionally you’ll find one that’s a bit gritty in its rotation. If that’s the case, get hold of another! (We showed you how to scrounge the video head from a VCR in “Salvage It!” in the December 2005 issue.) The VCR used here cost just $1 from a garage sale. Second, you’ll need an old cassette player, preferably a battery/mains portable. It doesn’t matter if it’s stereo or mono but go for a small design that uses an amplified speaker. We picked one up for $3 – knocked down from the $5 being requested at a garage sale. Third, you’ll need an old computer mouse of the sort that uses a ball. We already had one stuffed away in a drawer, so that part didn’t cost anything. And last of all, you’ll need an electronic speedo or tacho from a car. Alternatively, if you can’t lay your hands on one of those, you can use a VU meter from an old cassette deck (see “Salvage It!” in the June 2005 issue for more on using salvaged VU meters). The speedo used here was bought at a local metal recycler for $3 – in fact, to be accurate, that price also included the tacho and the vacuum fluorescent fuel and temperature gauges! They’re the major bits but in addition you’ll need some discrete electronic components – some of which almost certainly can be ratted from the VCR. You also need three kitchen measuring spoons, a short length of 90mm plastic pipe and some 90mm plastic end caps. The design So how do we turn all those bits and siliconchip.com.au In this view, you can see from top to bottom, the stainless steel measuring spoons that form the cups, the upper section of the video head, the shaft, the upper pipe cap, the lower section of the video head containing the bearings, the slotted optical wheel and sensors, and the mouse circuit board. The slotted optical sensor wheel is glued to the end of the shaft. The mouse circuit board is mounted so that the slotted wheel interrupts the light beam between a LED and its adjoining sensor – just as it did in the mouse. Only one of the two mouse sensors is used (the unused one can be seen at bottom left). pieces into an anemometer? In summary, the video head provides the lowfriction ball bearings, hardened steel shaft and aluminium bearing housing. The measuring spoons – they’re usually stainless steel – are used to form the anemometer cups (they mount on one end of the shaft). The computer mouse donates the LED/phototransistor pair and also the finely slotted wheel that interrupts the light beam as it spins. These components are used March 2006  91 Fig.3: this diagram shows how the mouse, cassette player and charge pump are interconnected. Note that only the existing external connections to the cassette player PC board are used – you don’t need to probe into its internal circuitry. The regulated power supply is optional – in most cases, the original cassette player power supply can be used without modification. to generate a frequency that varies in proportion to wind speed. The signal from the mouse is then amplified by the cassette player and fed into a charge pump circuit that comprises just a handful of passive components. This circuit converts the frequency into a voltage which is then read on the car speedo (or VU meter). If you use a speedo, you’ll be able to read the wind speed directly in km/h from the dial. By altering the charge pump capacitors, a variety of meters can be catered for. To make it all happen you don’t need to get deeply into the intricacies of the circuits of the mouse, cassette deck or speedo – provided you have a frequency reading multimeter, it’s all pretty straightforward. Main Features • • Large analog display • Works down to very low wind speeds • • • Linear or non-linear scales Span can be set to suit local wind conditions Makes use of junked equipment Very cheap to make 92  Silicon Chip Fig.1 shows a block diagram of how the anemometer works. Building it The key to making the anemometer is to build it in the right sequence of steps – that way, you can test each part of the system as you go along. THE OPTICAL SENSOR: the mouse is used to provide the optical sensor of the anemometer. The PC board in the mouse remains intact – we just tap into it to extract the signal. The first step is to power up the mouse and then find the signal output, which is taken directly from the photosensor. Fig.2 shows the pin-outs of the plugs used on PS2 mice. In this application, we need to use only the power supply and ground connections. Open up the mouse, cut off the cable and then use Fig.2 to identify the power and earth leads. Apply 5V to these leads (the voltage doesn’t have to be absolutely precise, so four partially flat 1.5V cells are fine, or you can use an adjustable bench power supply) and then use a frequency measuring multimeter to probe the pins of one of the two internal light receptors (positive probe of the meter to the device and negative to the ground wire). Alternatively, you can probe the pins of the IC to find the same signal. Now spin the small slotted wheels by hand and keep probing until you find a pin that has an output frequency that increases with the speed of one of the wheels. In the prototype, this varied from about 40-2000Hz. Of course, if you have one, a scope is ideal for this sort of pin finding. Carefully solder a wire to this signal pin. The output of the sensor is likely to be a varying DC signal. In fact, you don’t even need a frequency measuring multimeter to check this – just use your trusty old analog multimeter switched to a low DC voltage range. At low frequency outputs, the needle will flicker faster or slower, depending on the speed of the wheel. To block this DC component of the signal, wire a 470nF (0.47mF) capacitor in series with the output – this converts the signal to an AC waveform. You now have an optical sensor with a high-resolution frequency output! THE AMPLIFIER: the cassette deck is used to amplify the small signals coming from the optical sensor. To achieve this, the signal output from the optical sensor is connected to the tape head input of the cassette player. Access the cable that goes to the tape head. In most cheap cassette players, this will comprise just a single signal wire inside the shield. Connect this signal wire to the signal output of the optical sensor, then connect the shield of head input wire to the ground wire of the mouse. siliconchip.com.au The mouse circuit board is held in position by a bracket formed from scrap aluminium sheet. Note that heatshrink has been used as an insulator between the board tracks and the bracket. Now power up both the cassette player and the mouse, set the cassette player volume to full and press the “play” button. When you spin the optical wheel in the mouse, you should hear a noise from the cassette player’s speaker that changes in pitch with wheel speed (in fact, if all you want is an audible wind speed indicator, you can pretty well stop right now – the wiring part of the project finished!). If you have difficulty finding the right wires from the head (perhaps because there are four wires or multiple heads), touch the different head connections with a finger while the tape player is running. Touching the correct signal wire will result in a loud hum in the speaker. (If you are using a mains-powered cassette player, you should take care that you cannot come into contact with high voltages. In this case, it is best to extend the head wires outside of the case and then temporarily close it up again.) Because the amplifier has very high gain, it is susceptible to picking up noise. To reduce this, a 1kW pot is wired across the mouse output, with the wiper connecting to the amplifier. In use, this pot is adjusted so that adequate signal is provided without there being too much noise present (indicated by lots of noise in the speaker even with no rotation of the wheel). This wiring – and in fact the complete circuit of the anemometer – is shown in Fig.3. You now have a high gain amplifier suitable for amplifying the output of the optical sensor! siliconchip.com.au THE SPINNING ASSEMBLY: disassemble the video head, gutting it of any electronics that you see. Pulling the head apart usually requires a Phillips head screwdriver and a small metric Allen key. Some brass collars are also a light press-fit on the shaft – these can be removed by gently using a hammer and a punch. Prise out the black magnetic material that is within the head. It easily shatters, so be careful when doing this – it’s best to wear safety glasses when performing this operation. Once you’ve got the head bare, you can build the impeller. We used three small (1 teaspoon or 20ml) measuring spoons from a supermarket. These particular ones were made of stainless steel with a non-slip (and noncorrosive!) coating. The spoons were bolted together, using the existing holes located at one end of the handles. The spoons were then spread evenly (ie, with a 120° spacing) and matching holes were drilled through the spinning aluminium housing and the handles of the spoons. The spoons were then bolted in place using short screws and nuts and once this was done, the heads of the spoons were carefully twisted through 90° to form the anemometer cup assembly. The completed assembly should spin freely in even the lightest puff of wind. If the assembly is out of balance, hold the shaft horizontally and see which cups always points downwards. Place a small weight on the side opposite. Getting the assembly well-balanced yields dividends The spinning disc has lots of slots in it – we counted 40 but that might not be right! In any case, the output resolution of the sensor is very good – if you wish, you can calibrate the scale to read wind speeds of just a few kilometres per hour. Stainless steel measuring spoons were used to form the anemometer cups. These were bought (gasp!) new for the project. in longevity – an out-of-balance shaft puts a greater load on the bearings. The half of the video head that contains the bearings is bolted to the inside of a 90mm PVC pipe cap. As with the rotating part of the head, some new holes will probably need to be drilled through the aluminium for the mounting bolts. The next step is to fit the slotted mouse wheel to the opposite end of the shaft to the cups. Cut the slotted encoder wheel off its plastic shaft and then use a fine flat file to smooth each side, being careful not to burr the tiny March 2006  93 The rotating assembly can be balanced by adding weights – here a bolt and some extra nuts (arrowed) have been placed on one side of the assembly. The speedo was mounted in a small picture frame. Note that it is easy to backlight the dial – all car speedos have this facility and in some, even the needle is illuminated! slots. Then, using instant adhesive, very carefully glue the slotted wheel to the end of the anemometer shaft. It needs to be perfectly concentric; ie, when the shaft is turning there is no run-out. The mouse PC board is mounted so that the slotted wheel spins between the LED and its adjacent photosensor. We used a small piece of scrap aluminium to make the locating bracket. Note that if the shaft has a tendency to slide downwards through the bearings, so causing clearance problems between the slotted wheel and its sensor, place a drop of instant glue on the shaft right next to a bearing before A Fun Instrument If you want a fun instrument rather than a calibrated km/h design, simply pick capacitors in the charge pump that give full-scale deflection of the speedo when the cups are quickly flicked. Then use a computer, scanner and printer to make a scale that shows wind speeds like “Boring”, “Some Excitement”, “Hell It’s Blowing”, “Where’s The Cat Gone?”, “Take Shelter!” and “Are We Still Alive?”. sliding it through the bearing to the correct position. You now have a very sensitive and durable spinning anemometer head with a variable frequency output! THE DISPLAY: the display can comprise an electronic car speedo or tachometer, or a cassette deck VU meter. The car instruments make for a much more impressive readout, so we’ve used one of those. In any case, we don’t need the frequency-to-voltage converter that’s used within these car instruments; instead, as mentioned above, we make our own charge pump system. Doing this means that we can match the amplified output of the optical sensor to a very wide range of meters, as well as easily changing characteristics like smoothing and range. Remove the speedo or tacho and strip it down until just the meter and its electric movement remain. When a low voltage (eg, 2V) is applied, the meter should swing full scale. Take note of the positive and negative leads, as revealed by this test. If you’re using a speedo, you should be able to retain the standard km/h scale. Alternatively, if you use a tacho or you want the scaling to be different Fig.4: this charge pump circuit is used to convert the amplified frequency signal from the mouse to a DC signal proportional to the wind speed. 94  Silicon Chip to the original on the speedo, a new scale will need to be made using a scanner, PC and printer (see “Salvage It!” in the March 2005 issue for more on rescaling car tachos). In this case, the positions of the increments will be found during the calibration procedure (see below). You now have a large analog anemometer readout! POWER SUPPLIES: two voltages need to be provided: 5V to the mouse circuit and (usually) 6V to the cassette player (we now know these components as the optical sensor and amplifier, respectively!). If absolute accuracy in the wind speed readout isn’t required, the amplifier can be powered directly by the mains, batteries or a plugpack – whatever was originally used by the cassette player. The down-side of this approach is that the displayed wind speed will vary with supply voltage fluctuations. This is because the square-wave amplified output is driven from rail to rail – the cassette player is no longer acting as a feedback amplifier. The alternative is to use a voltage regulator, which is what we chose to do. As well as providing better instrument accuracy, this also allows easy calibration in a car as the system can be powered from the car supply. We powered the regulator from a spare plugpack we had previously salvaged. The supply for the optical sensor is obtained by simply using a 10kW pot across the power feed that originally went to the cassette player motor, adjusted to provide 5V when loaded by the optical sensor. Fig.3 shows the power supply wirsiliconchip.com.au ➊ ➎ ➋ ➌ ing, both for the amplifier and the optical sensor. FREQUENCY-TO-VOLTAGE CONVERTER: the frequency-to-voltage converter (charge pump) is the final stage in the build and is best optimised on the bench with the whole system working. Fig.4 shows the way in which the charge pump works. For the moment, disregard the variable resistor VR1. Initially, C1 and C2 are discharged. When the input voltage goes high, C1 starts to charge through D1 and C2. Because C1 is much smaller than C2, C1 fully charges earlier than C2 and when this occurs, current stops flowing. However, during this process, C2 has received a small charge increase. When the input voltage goes low, C1 discharges through D2, but C2 does not discharge because D1 blocks the discharge path. The result is that each time the input voltage goes high, a small amount of charge is added to C2, resulting in C2’s voltage rising in proportion with the input frequency. C2 powers the meter; ie, C2 is being constantly discharged by the meter’s load. VR1 allows adjustment of the meter’s deflection for a given voltage level across C2. C2 should be kept as low as possible but must be sufficient to provide a damped meter movement at the lowest frequency output at which the amplifier will work. If the speedo needle flickers when the cups are turned at the slowest speed at which you will be making measurements (this value desiliconchip.com.au ➍ pends on the scale you have chosen), then C2 needs to be increased until the needle moves smoothly. C1 needs to be small enough to allow it to fully discharge during the time that the input signal is low. In the prototype, where the car speedometer has a 100W resistance, C1 comprises two 10mF electrolytic capacitors (wired negative to negative to make the pair non-polarised), while C2 has a value of 220mF. The 16W resistor in series with C1 reduces the peak current through the amplifier. Note that if you are using a VU meter instead of a car speedo, C1, C2 and the resistor in series with C1 will all be much lower in value. It all starts to sound a bit compli- The basic layout: (1) cassette player circuit board, being used as an amplifier; (2) pot that provides the 5V supply to the mouse board; (3) voltage regulator and associated capacitors powering the amplifier (only required if there will be major mains supply variations); (4) amplifier input attenuating pot and capacitor; (5) charge pump circuit. Incidentally, the expensive looking NEC pots were bought very cheaply on eBay. cated but when you realise that the frequency-to-voltage charge pump circuit uses only six low-cost components, you can breathe easily again! To find the best values for C1 and C2, initially lash up the anemometer circuit on the bench – power supplies and all. Start with the capacitor values cited above and set VR1 so that its resistance is as low as possible. Spin the anemometer cups by hand – rotating them fairly slowly – and check that the speedo (or VU meter needle) smoothly deflects a little. Now spin the cups faster and check that the deflection is greater. Adjust VR1 and check that the deflection for a given cup speed is reduced. If the deflection is too small, in- This is the cassette player that donated its amplifier. In many cases it will be easiest to use the original cassette player power supply and mount the new components inside. The garage sale purchase price was knocked down form the marked $5 to $3. March 2006  95 player PC board to mount it in a new box, keep in mind that you must bridge the switch that is normally activated when the “Play” button is pressed – otherwise, the amplifier won’t work. The display is easily mounted remote to the main box, so if retaining the cassette player housing, it’s easy to tuck it out of sight. While it might appear that the distance between the head and amplifier should be kept very short, we had no difficulties in stretching this distance to 25 metres, using salvaged multi-core alarm cable. Calibration The working anemometer, seen positioned high on the roof. The cup covering the centre section of the rotating assembly was made from an aerosol cap. For improved durability, everything you see here should be painted. crease the value of C1. If the needle deflection becomes non-linear at high speed (ie, its deflection is much less than expected), reduce the value of C1 and then reduce C2 proportionately. In short, just play around with the capacitor values (always keeping C1 much lower than C2) until the needle behaves as wanted over a variety of cup speeds. Note that as a set-up guide, a fast flick of the anemometer cups will spin them to a wind speed of about 40km/h. If you only want to measure wind speeds up to 50 km/h, size the capacitors so that you get nearly full scale deflection with a fast whiz of the cups. Final assembly The rotating assembly is completed by adding the short section of 90mm plastic pipe and the second end-cap. Use PVC pipe adhesive to glue these parts together. Alternatively, if you want to be able to easily disassemble the container, use self-tapping screws to hold one of the end-caps in place. Make sure you seal the hole where the cable exits. Note that the anemometer is orientated so that its rotating cups are below the plastic housing – this helps prevent the ingress of water. The prototype was mounted using square aluminium tube. This tube was bolted to the upper end cap. We mounted the electronics in a new box. The cassette player PC board was removed from its original case. However, especially if you are going to use the cassette player’s power supply, we suggest that you leave everything inside the cassette player, placing the charge pump and other minor components inside. If you remove the cassette Rat It Before You Chuck It! Whenever you throw away an old TV (or VCR or washing machine or dishwasher or printer) do you always think that surely there must be some good salvageable components inside? Well, this column is for you! (And it’s also for people without a lot of dough.) Each month we’ll use bits and pieces sourced from discards, sometimes in mini-projects and other times as an ideas smorgasbord. And you can contribute as well. If you have a use for specific parts which can 96  Silicon Chip easily be salvaged from goods commonly being thrown away, we’d love to hear from you. Perhaps you use the pressure switch from a washing machine to control a pump. Or maybe you have a use for the highquality bearings from VCR heads. Or perhaps you’ve found how the guts of a cassette player can be easily turned into a metal detector. (Well, we made the last one up but you get the idea . . .) If you have some practical ideas, write in and tell us! Calibration is easily achieved by placing the whole device in a moving car, locating the rotating assembly outside, and then calibrating against the speedo reading. Just make sure that you do the calibration on a still day! The device can be powered by the car supply or the cassette player’s internal batteries. If you are using a preformed, linear scale, setting the correct needle position with VR1 should be done at a couple of speeds. Note that because of non-linearities in the anemometer aerodynamics, amplifier and meter, you won’t get a perfectly accurate readout at all wind speeds – but you should be within 10% everywhere. If you are devising your own scale, start with one with linear markings (eg, 1-10) on the scale. Write down the wind speed at each of the markings are then print out a revised scale with these speeds in the correct positions. Incidentally, if you want to decrease the sensitivity to high wind speeds (ie, expand the lower wind speed scale), tweaking the value of C1 upwards will do this for you! Conclusion This is a fun and engrossing project to make – from disassembling the mouse and video head, to trying different charge pump capacitor values to give you the scale and sensitivity that you want. The anemometer is sufficiently sensitive to spin with wind speeds of just 2-3km/h (and has an output resolution to measure those speeds too!) and if well balanced, is still rugged enough to cope with high speeds and full weather exposure. Best of all, it makes use of a heap of stuff you’d otherwise just throw SC away! siliconchip.com.au SEE OUR WEB SITE FOR MORE 200W WIND GENERATOR WITH SLIP RINGS!!! NOW ON SALE FOR ONLY $399 Unlike many similar wind generators these have slip rings so as the main cable will not twist off. These are serious 3ph 200W wind generators with blades spanning 2.2M. 12V. Included is a 6M mast with guy wires and turnbuckles etc. and a three phase shunt / charge controller unit with voltage and amperage metering. 1 X 45kg box (720 x 440 x 230mm), & 1 X 27.5kg box (1540 x 220 x 110mm). For more information and instructions see our Website.... oatleyelectronics.com COIN HOPPER WITH COIN DISPENSING / COUNTING MECHANISM. This mechanism was designed as part of a vending machine, it suits $1AU coins. It has a 24V motor & gearbox (all metal gears) & an optical $12ea switch to count coins. At 1.8V OR the motor will start running, it is 3 for difficult to stop $27 the output shaft with your fingers (HOP) at this voltage. The two 8mm gearbox output shafts turn in opposite directions, they have a flat on each & our SPR300 sprocket fits the shaft. The combination of our SPR300 11 tooth sprocket & our CHAINSP 80 tooth chain and sprocket set would give a slow & powerful output (approx. 15RMP <at> 24V or 0.96 RPM <at> 2V). This motor & gearbox with chains & sprockets could be used to open doors & gates etc. (see our garage door controller kit K023C).Some approx. voltage/current & RPM figures of the motor/gearbox. 2V 80mA 7RPM, 6V 100mA 30RPM, 12V 120mA 60RPM, 18V 140mA 110RPM, Overall dimensions of the hopper assembly: 93mm(W) X 126mm(L) x 126mm(H). FANTASTIC NEW PRODUCT 1W LED WITH THREE MODES OF OPERATION This LED will simply turn on when connected to power or with the addition of a pushbutton it can be set to full power, half power or flash. This LED is so bright and so fast that it looks almost like a strobe. It would be ideal for use as a safety light or a headlight for a bike. Full specs. on our web site. (3ML)$9.90 + $9.90 DVD QUALITY TV RECEPTION... TERRESTRIAL DIGITAL TV ON YOUR COMPUTER FOR LESS THAN $100 No more analogue TV after 2008? Enjoy the superior sound & picture quality of free to air digital TV. So good you will enjoy watching the ads. Simply load the software. Plug in an antenna & plug this amazing little metal box into your USB port. So small that RX434A SUPERHETERODYNE RECEIVER it's ideal for laptop computers, measuring only 64mm(L) MODULE: Pre-built superheterodyne surface mount receiver module which is crystal locked at 433.92MHz. X 22mm(W) X 9mm(T) (plus connectors 87mm(L)). The It has a high sensitivity, operates from 5V DC supply. It software allows you to record, take snapshots, Time Shift & lots more. Terrestrial Digital TV is available in most is designed for use with TX434A. When used in places where normal free to air TV is available. It is conjunction with TX434A, the pair can give a range of expected that normal analogue free to air TV over 1km when the transmitter is powered by 9VDC. transmissions will end in 2008. Some of the features of Frequency:433.92MHz digital TV that are now or will be available include sports Transmit rate: 9.6KB/S multi-view, Electronic Program Guides (EPGs), Closed Modulation: A.S.K. Captions & digital radio, while SBS & the ABC often Voltage:5VDC <at> 2.6mA broadcast different programs on multiple channels at the Size: 35mm X 17mm same time. Most of these features are available now. (RX434A) $8 Comes with installation software. (DTVM). See our TX434A SUPER-REGENERATION TRANSMITTER Website for more info on this amazing device. MODULE: Pre-built superheterodyne surface mount SPECIAL INTRODUCTORY transmitter module which is crystal locked at 433.92MHz. Operates from 3-12V DC supply. It is designed for use PRICE OF JUST $89 with RX434A. When used in conjunction with RX434A, can give a range of over 1km when K229 AUDIO / VIDEO TRANSMITTER / RECEIVER KIT the transmitter is powered by 12V DC. This kit (K229TX & K229RX) are designed to transmit Frequency:433.92MHz and receive video and stereo audio. The TX has been Transmit power: 10mW <at> 12V designed to be as small as practical. (TX kit) Modulation: AM 13mm(H) X 30mm(W) X 30mm(D). Voltage:3-12VDC <at> 15mA (RX kit) 17mm(H) X 50mm(W) X Size: 14mm X 14mm (TX434A) $6 62mm(D) with connectors). NEW LED MR16 TYPE LAMP Construction is simple and the preThese lamps are a direct replacement for MR16 halogen built modules mean minimal work is down lights. they will operate from 12V AC or DC at required and there is no tuning to be 150mA making them ideal for use in solar installations. done. The antenna can be as simple During March you can buy a ceiling gimble mount with as a 31mm length of un-shielded stiff wire or another socket for just $2 with very antenna can be connected remotely via co-ax cable. An lamp purchased (subject to antenna such as our K198 2.4GHz TX / RX ANTENNA availability). (LED21W) KIT can be added. This antenna kit will increase the $13ea range of the K229. The K198 is a 2.4Ghz antenna printed on a circuit board, it has been tested with our previous A/V TX/RX kit and gave good a good image at over 100M. These kits are designed to operate from a 9VDC supply. **NEW**NEW**NEW** We have new replacement UHF434 TX and RX modules. These give equal or better range than our previous modules. (K229T) $17 JUST $13ea. ADD $2 FOR A GIMBLE CEILING FITTING DURING MARCH THEY ARE BACK IN STOCK ELECTRIC MOTORS, BATTERIES AND SPEED CONTROLLERS 100W, 200W, 300W AND NOW A MASSIVE 500W NEW OZONE AND NEGATIVE ION GENERATORS ION & OZONE GENERATOR MODULES ION MODULE ION MODULE WITH CARBON HEAD DUAL GENERATOR(-ION & OZONE) MODULE WITH HEADS 12-24V Dual Battery Adapter for a vehicle. This kit simply switches an Auxiliary battery across the main battery only when the main battery is fully charged. It will only then charge the second battery. When the battery voltage drops the k227 will isolate the batteries to stop overdischarging of the primary battery. The kit includes all o n b o a r d components, PCB and an 80A single coil Latching relay. (K227) $19 $19 NEW KITS COMING SOON NEW BIRD SCARER - 24 SECOND VOICE / SOUND RECORDER MODULE This small pre-built module will record up to 24 seconds of sound at the push of a button, then play it back at the push of a second button. Requires 6VDC to operate. Measures 34mm X 22mm Comes with a 29mm speaker VRM1$10 (K229R) $33 Protect your vegie garden or fruit trees from those pesky pigeons, starlings and Indian minor birds. This new Kit generates a random output reducing the chances of birds becoming accustom to the output. UNIPOLAR (6 WIRE) STEPPER MOTOR DRIVER All operate from 12V-30mA DC..Produce up to 10KV OUTPUT. Info on Web Site.. These could suit other applications like Electrostatic Speakers etc. Warning: Ozone destroys mould and germs and is used in water purification systems. Its concentration has to be limited for humans. Research before using! This kit will drive 6 wire motors from a computer and is designed to work with our K142 computer to stepper motor interface (CNC) series of kits. To be notified the moment that these kits and other items kits become available subscribe to our mailing list at oatleyelectronics.com For more info and pricing go to our Website. www.oatleyelectronics.com Suppliers of kits and surplus electronics to hobbyists, experimenters, industry & professionals. Orders: Ph ( 02 ) 9584 3563, Fax 9584 3561, sales<at>oatleyelectronics.com, PO Box 89 Oatley NSW 2223 OR www.oatleye.com siliconchip.com.au March 2006  97 major credit cards accepted, Post & Pack typically $7 Prices subject to change without notice ACN 068 740 081 ABN18068 740 081 SC_MAR_06 Vintage Radio By RODNEY CHAMPNESS, VK3UG The Healing “Scales” 403E receiver In the late 1940s, the main household receiver was usually located in the lounge or dining room – and usually controlled by the “man of the house” in line with the rather chauvinistic attitudes of the time. However, small 4-valve mantel receivers designed for use in the kitchen were also becoming quite common. O NE LIMITATION ON the use of multiple sets in a household was the radio receiver licensing regulations. Initially, they required a licence for each individual “wireless” and in fact, back in the sealed receiver era in the 1920s, a separate licence or fee was payable for each station that a person wished to listen to. Fortunately, this idiotic idea was overturned within a rather short time. However, with one set per licence, there was no incentive to buy more than one set and receivers were expensive anyway. Retailers had to submit a return to the PMG on what sets they sold and to whom, so it was not too hard for the authorities to find out who had unlicensed sets. The mandatory outside aerial was also a dead give­ away. Of course, many home-built sets were never licensed. Eventually, the licensing regulations were eased and the household licence came into being, allowing several sets to be used. Ultimately, domestic radio and television licensing was abolished on 1st September, 1974. To read more about this subject, go to: http://wireless.iserv.com.au/default. asp?m=main&id=age3 The Healing “Scales” The Healing 403E – it looked rather like a set of kitchen scales and was often affectionately called the Healing “Scales”. 98  Silicon Chip To meet the need for more than one set in the household, many manufacturers produced small lowperformance 4-valve sets. Healing was one of those manufacturers and produced many sets. One that has taken the fancy of many collectors is the Healing 403E or as it is affectionately called by some, the Healing “Scales”, supposedly because it looks like a set of kitchen scales. The set came onto the market around 1950. It would appear that it is designed to be placed on the kitchen bench as the dial scale is on the slopsiliconchip.com.au Fig.1: the circuit for the Healing “Scales” 403E receiver. It uses a 6AN7 frequency converter, a 6AR7-GT IF amplifier & detector, a 6M5 audio output stage and a 6X5-GT rectifier. ing top of the set. It is then really a bench top or table set and not a mantel receiver. It was quite an innovative concept although in the kitchen environment it may have been splashed with water or food. However, despite the potential abuse, the sets survived quite well. The receiver is separated quite easily from its cabinet, requiring the removal of three screws in the Bakelite base, four screws attaching the chassis and the cabinet top together and the two control knobs. Warning: once the set is removed from the cabinet, do not tip it upside down onto the dial scale, as it will break. To make sure the dial scale is not damaged, remove it and put it aside until alignment or reassembly is to take place. This receiver had not been restored at the time of writing. Access under the chassis is quite good and any component there can be adjusted or replaced readily. However, caution is needed when operating this receiver out of its case as the mains terminations are exposed on the bottom of the power transformer. If the set were mine, I would put a protective insulated cover over these terminals. It would be all too easy to touch these exposed terminals while concentrating on other aspects of the restoration process. siliconchip.com.au A rear view of the chassis out of its cabinet – note the very tight layout. The receiver uses just four valves. Of course, the twin flex should be replaced with a 3-core mains lead, so that the chassis can be earthed. Suitable replacement power leads are available as extension cables of various lengths at most supermarkets. Just cut off the socket and you will have a lead ready to wire into the chassis. Better still, you can often salvage perfectly good 3-core power cords during council cleanups, as people often discard computers and other appliances. Above the chassis, the components are tightly packed in and some dismantling would be required to work March 2006  99 This view shows the chassis from the front. The parts on top of the chassis were rather tightly packed. Another view of the chassis from the front, this time with repaired (left) and replacement dial scales. on a few items. Fortunately, work here is not required as often as underneath the chassis. Circuit highlights The Healing 403E is really a 3-valve plus rectifier receiver, similar to many 100  Silicon Chip sets produced by other manufacturers of the era. A 6AN7 is used as a frequency changer with an output of 455 kilohertz (kHz) to an IF amplifier using the pentode 6AR7-GT as the amplifier. The two diodes in the 6AR7-GT enve- lope act as the detector and automatic volume (gain) control (AGC). The AGC is simple and only a third of the AGC voltage is applied to the 6AN7 and the 6AR7-GT via the voltage divider of R2 (1MW) and R5 (2MW). The audio (and AGC) voltage is applied across R6 which is then applied to the grid of the 6M5 audio output valve. The converter and IF amplifier are run with no bias on their grids but because their screen voltage is only around 50V, the current drain is not excessive. There will be a small amount of bias provided from the AGC line, even off-station, as any circuit noise and external interference will generate an AGC voltage, small though it may be. Tuned to a station, the bias is significantly higher. By only applying a third of the developed AGC voltage to the two controlled valves, more signal is able to be applied to the 6M5 to achieve a reasonable audio output level. As a purist, I find only applying a third of the available AGC voltage is a poor design feature. However, when it is considered where the set was intended to be used – suburban areas not far from radio stations – it works quite satisfactorily. The 6M5 has the common cathode bias method, which provides around 6V of bias with a current drain of around 25mA in this receiver. The total current drain of the receiver is around 37mA from the 6X5GT rectifier. Those with a sharp eye will have picked up drafting errors in the published circuit. The secondary winding of L4 (second IF transformer) appears to go to the grid of the 6AR7GT but should connect to a diode or both of the diodes within the 6AR7-GT. The oscillator grid is also not shown connected to the third grid. Labelling the valve pin numbers would also help servicemen and restorers. It is amazing the number of drafting errors that did creep in. Overhauling the set Simple receivers like the 403E do not require many paper capacitors to be replaced when compared to more complex 5-valve designs. Most of the paper capacitors in this receiver can be quite leaky and still not cause any noticeable or dangerous problems. The only critical one is C3, the AGC bypass capacitor, and this should be replaced as a matter of course. The siliconchip.com.au VALVES AUDIO HI-FI AMATEUR RADIO GUITAR AMPS INDUSTRIAL VINTAGE RADIO We can supply your valve needs, including high voltage capacitors, Hammond transformers, chassis, sockets and valve books. WE BUY, SELL and TRADE SSAE DL size for CATALOGUE The is the under-chassis view. Note that the power cord terminations are quite exposed and that only 2-core flex has been used – it should be replaced with a 3-core lead, so that the chassis can be earthed. The mains transformer has also been overheating, as revealed by the congealed wax on the bottom of the windings. audio coupler (C11) has only a small voltage across it (a maximum of around 20V). If this is leaky, all it will do is place a negative voltage on the grid of the 6M5 and progressively cut it off as the volume control is increased or a stronger station is tuned in. C13, if shorted, would just cause the audio to disappear but no damage would be done to the set. Electrolytic capacitors C8 and C14 should be reformed if necessary, after being tested with an ohmmeter to ensure there are no short circuits between the high tension (HT) line and the chassis. My rough and ready technique is to place a voltmeter across C14, turn the set on and wait until the voltage across it starts to rise. Once it has risen to 50V or so, I switch off and then, about 30 seconds later, I repeat the procedure, this time letting the voltage rise to around 100V before switching off. Do this over a period of several minutes and the electrolytic capacitors should be reformed. However, watch the voltmeter and the rectifier when doing this, making sure the rectifier doesn’t look as though it is overheating (the plates will go red, if this happens) and that the voltage siliconchip.com.au does increase rapidly once the rectifier starts to conduct. After the preceding tests, check with the power off to see if the electrolytic capacitors are warm to the touch. If they are, they should be replaced, as they are defective. The set should also be run for a while to make sure the power transformer only gets moderately warm. In this set, it is obvious that the power transformer has dripped some wax, so it has been hotter than it should be. Before doing too much on this set, it would be advisable to do checks on the transformer for shorts and insulation integrity, as well as checking the rectifier and electrolytic capacitors for potential shorts or low resistance to earth (chassis). Initially, the set should be run with the transformer lightly loaded, by taking out all the valves and leaving just the dial lamps in. If it gets other than slightly warm, the transformer may have a fault. If all is well, the general tests indicated in the previous paragraphs should be undertaken. The problem may have been fixed sometime in the past but it does pay to be very sure that there is no latent fault in the power supply area. Manufacturers often skimped on ELECTRONIC VALVE & TUBE COMPANY PO Box 487 Drysdale, Vic 3222 76 Bluff Rd, St Leonards, 3223 Tel: (03) 5257 2297; Fax: (03) 5257 1773 Email: evatco<at>pacific.net.au www.evatco.com.au Silicon Chip Binders REAL VALUE AT $12.95 PLUS P & P H SILICON CHIP logo printed in gold-coloured lettering on spine & cover H Buy five and get them postage free! Price: $A12.95 plus $A7.00 p&p per oder. Available only in Australia. Just fill in the handy order form in this issue; or fax (02) 9979 6503; or ring (02) 9979 5644 & quote your credit card number. March 2006  101 Photo Gallery: AWA 519M (1947) Manufactured by AWA in 1947, the 519M is another example of a popular 5-valve mantel receiver of that era. It was fitted into a bakelite cabinet, the brown-white mottled unit shown here being one of the less common cabinet colours. The valve line-up was as follows: 6A8-G frequency changer; 6SK7-GT IF amplifier; 6SQ7-GT audio amplifier/detector/AVC rectifier; 6V6GT audio output; and 6X5-GT rectifier. Photo: Historical Radio Society of Australia, Inc. fitting some components. In this case, a 100nF (0.1mF) or similar value capacitor has not been put across C8 to effectively bypass any RF energy on the HT line. When first installed, capacitors like C8 are reasonably effective RF bypasses but as time goes by, their effectiveness deteriorates and the receiver will often develop an instability problem. Although this set has not been restored as yet, I would expect that very little would have to be done for it to function quite satisfactorily. I rarely find that any valves need replacement, providing the critical capacitors are replaced before the set is turned on. Aligning the set This is a comparatively easy set to align, with a total of eight adjustments. Basically, the four tuning slugs in IF amplifier transformers L3 and L4 are peaked for best performance on a relatively weak signal at 455kHz. It is not imperative that the frequency be exactly 455kHz as long as it is within about 10kHz of 455kHz. The front-end alignment is a little more exacting, as several frequencies The Latest From SILICON CHIP are involved. The dial scale needs to be attached to the receiver so that the alignment can be done with accuracy. Take note of the warning earlier in the article about how easy it is to damage the dial scale. The data I have on the receiver is not specific about the spot frequencies used in the front-end alignment. As a general rule, 600kHz and 1500kHz are usually used. If you don’t have a signal generator, tuning to stations near to these frequencies is quite adequate, like 621kHz for 3AR (3RN) and 1521kHz (2QN) in my area. First, tune to around 600kHz and adjust C6 (under the chassis) until the particular station selected appears at the correct spot on the dial. Then adjust the core of L1 for best volume on this station or a weak one nearby. Now tune to a station near 1500kHz and adjust C4 (on top of the gang) so that the station tuned to appears at the correct spot on the dial, and then peak C1 (on top of the gang) for best performance. Go over the adjustments for 600kHz and 1500kHz several times, as they do interact with one another. For more information on these procedures, refer to my articles in the December 2002, January 2003 and February 2003 issues of SILICON CHIP. Summary This set is a quirky little receiver that doesn’t appeal to all, although highly sought after by many collectors. I believe that it would be easily restored. The performance is on a par with sets of a similar design. The design of the AGC system means that it really hasn’t enough gain to produce good performance in country areas but it would be quite adequate in suburban locations. I wouldn’t say no to having SC one in my collection. 160 PAGES 23 CHAPTE RS Completely NEW projects – the result of two years research & development • Learn how engine management systems work • Build projects to control nitrous, fuel injection and turbo boost systems • Switch devices on and off on the basis of signal frequency, temperature and voltage • Build test instruments to check fuel injector duty cycle, fuel mixtures and brake & temperature Mail order prices: Aust. $A22.50 (incl. GST & P&P); Overseas $A26.00 via airmail. Order by phoning (02) 9979 5644 & quoting your credit card number; or fax the details to (02) 9979 6503; or mail your order with cheque or credit card details to Silicon Chip Publications, PO Box 139, Collaroy, NSW 2097. 102  Silicon Chip From the publishers of Intelligent turbo timer I SBN 095852294 - 4 9 780958 522946 $19.80 (inc GST) NZ $22.00 (inc GST) TURBO BOOST & nitrous fuel controllers How engine management works siliconchip.com.au SILICON CHIP Order Form/Tax Invoice Silicon Chip Publications Pty Ltd ABN 49 003 205 490 www.siliconchip.com.au PRICE GUIDE: SUBSCRIPTIONS YOUR DETAILS (Note: all subscription prices include P&P). (Aust. prices include GST) Your Name________________________________________________________ (PLEASE PRINT) Organisation (if applicable)___________________________________________ Please state month to start. 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Card expiry date: Signature_____________________________ SUBSCRIBERS QUALIFY FOR 10% DISCOUNT ON ALL SILICON CHIP PRODUCTS* * except subscriptions/renewals Qty Item Price Item Description Subscribe to SILICON CHIP on-line at: www.siliconchip.com.au Both printed and on-line versions available Total TO PLACE YOUR ORDER siliconchip.com.au P&P if extra Total Price BUY MOR 10 OR ISSU E BACK ES A 1 0 & G ET DISC % OUN T $A Phone (02) 9939 3295 9am-5pm Mon-Fri Please have your credit card details ready OR Fax this form to (02) 9939 2648 with your credit card details 24 hours 7 days a week OR Mail this form, with your cheque/money order, to: Silicon Chip Publications Pty Ltd, PO Box 139, Collaroy, NSW, March2097 2006  103 Australia 03/06 ASK SILICON CHIP Got a technical problem? Can’t understand a piece of jargon or some technical principle? Drop us a line and we’ll answer your question. Write to: Ask Silicon Chip, PO Box 139, Collaroy Beach, NSW 2097; or send an email to silchip<at>siliconchip.com.au Are laser beams visible? A friend of mine is building a fullscale model Dalek from the good ol’ Dr Who series and wants to make a laser beam shoot out of its gun. I have looked around and found a couple of lasers such as the LM3 on the Oatley Electronics webpage (http://www. oatleyelectronics.com/lasers.html). The blurb for this unit states: “This module emits an orange/red beam which is more visible and brighter than the 650-670nm modules. Consists of a visible laser diode, diode housing, APC (automatic power control circuit) driver and collimation lens, all factory assembled in one small module”. Does this mean that you can actually see a beam of light coming out of the laser module? If so, how far would this beam travel? (C. G., via email). • In clear conditions, a laser beam or any light beam for that matter, cannot be seen travelling through air although you can obviously see where it lands on a surface. However, if the beam passes through dust, mist, smoke, etc, it will be visible. Perhaps you could use a fog machine to create the special effects that you desire. Depending on factors such as the lens, laser power and wavelength, the beam may travel many kilometres. IR train detector needs pulsed signal I have made several attempts to construct an IR train detector for my model train. I have found circuits in my model rail books dating back 10 years. I have also bought kits, some too expensive to duplicate and others where the parts are not clearly marked or the provider will not tell me the component values. The circuit I have sent to you is the easiest one I have found but the LED is on all the time when I apply 12V filtered DC. I have tried reducing the value of R1 and have also tried D1 and Q1 from different sources to no avail. Could you help me out here? I am Troubleshooting The Ignition System I successfully built the breakerless ignition project (SILICON CHIP, June 1988) and used it in two different cars until eight years ago when I bought a car with electronic ignition. I have now installed it in an older car running with points and after running for two weeks, it won’t go any more. I am aware of the latest High Energy Ignition system but I’d like to fix the old one, especially because I have some spare MC3334P ICs in stock. Basically, I need some advice how to troubleshoot it. I have replaced the IC without success. I am doing the troubleshooting on the bench (I use a spare coil, single spark plug, power supply, etc). When I rotate the distributor by hand, the spark plug will not 104  Silicon Chip fire. It will fire once when I connect the power, then nothing when turning by hand. The Darlington checks OK with a multimeter but I don’t know how to troubleshoot the IC. Can you please help? (G. D., Morwell, Vic). • First, with power applied, short the base of Q1 to GND. This turns off Q1 and should produce a spark each time you do it. If this is OK, the Darlington and output zeners are good. If this test is not OK, check the voltage at Q1’s base – it should be about 1.3V. If it’s 0V, IC1 is internally shorted. Now try pulling the junction of the 470kW & 22kW resistors to GND. This should cause a spark each time you do it. If OK, then Q2 may be suspect. a novice electronics user, although I have had previous success with other circuits. (G. J., via email). • We are unable to assist with troubleshooting circuits not published by us. We have not published an IR train detector but would suggest that you could base one on the IR Light Beam relay in the December 1991 issue or the Infrared Sentry in the April 1999 issue. Both circuits use a pulsed IR signal – any other approach is futile. Fixing Japanese radio frequency coverage I want to purchase a Japanese car audio system that has FM from 76.090.0MHz and AM from 522-1629kHz. However, I want to change both the AM and FM coverage to our Australian frequency range. The receiver has a digital screen interface but is not digital radio – just analog. There is a the link to the Japanese receiver at: (1) http://www.honda.co.jp/navigation/insight/audio.html (2) http://www.honda.co.jp/ACCESS/ gathers/audio/wx252m/index.html Is this possible to change? If so, what is the procedure for this? Would a firmware update be possible if I can find one? (Z. I., via email). • A firmware update would probably be the complete solution but we have no idea where you would get it. If you can find the OEM manufacturer, you might have a better chance. By the way, it should not be necessary to change the AM coverage unless it doesn’t step in 9kHz. The FM de-emphasis will probably be 75ms instead of the Australian standard 50ms and would probably require a capacitor change. Cheap LCD screen for reversing camera I wish to completely remove the LCD screen from some of those cheap 5-inch portable DVD players and turn them into usable screens for use with siliconchip.com.au reversing cameras for cars. Has any reader done this or can you advise on how to do this? Maybe you could do an article on a conversion. (S. V., via email). • It may not be possible to do this. There may be no point inside the unit to which you could connect an analog video signal since all processing, from the DVD to the LCD screen, is probably in the digital domain. Diode substitution in power supply I am building a 400V valve power supply following the article in the July 2004 issue. When I went to order some BYV26G diodes from RS Components I found that they have been discontinued. What would be a suitable alternative? Seeing that I am only building a 400V version, could I use the BYV26E diode (1000 PIV versus 1400 PIV for BYV26G)? Alternatively, could I use two of them in series to achieve the required voltage handling? (S. G., via email). • We expect that the BYV26E would be fine for the 400V version of the supply. Alternatively, the BY448 (Farnell stock No. 995-150) may be suitable, although we haven’t tried it. Air-bag aid for epileptic patient I do some work for TAD (Technical Aid for the Disabled). One of our clients has epilepsy and keeps falling over and has received some nasty injuries. We have been thinking about an airbag approach; ie, like in a car. Every­ one thinks there is not enough time. My estimate is that we would need to detect the fall and take action within about 150ms. Airbags take about 50ms to inflate. I was thinking about an MEMs sensor. Have any of your people any ideas or experience in this area? (J. J., via email) • Airbags certainly go off very quickly, as detailed in our article on the subject in the February 1994 issue. Typically they take just 30ms to inflate but they also deflate very quickly, at around 100ms. However, there would be real problems in adapting automotive air-bag technology because they activate so siliconchip.com.au Problem With Studio 350 Amplifiers I purchased two Studio 350 amplifier kits from Jaycar. I have years of experience in building kits and I thought I’d give this one a go. Unfortunately, after constructing one of the amplifier kits, I found that it didn’t work. Upon powering up, I observed that the output was not even close to 0V. It was almost full negative rail voltage. Before assembling the kit, I made sure that I had adjusted VR1 and VR2 to their midpoints so they wouldn’t cause any trouble later on. I turned the power off and checked that I had not connected anything the wrong way. After a long observation, I found no faults. I re-powered the circuit and the same thing happened. Even adjusting VR1 and VR2 made no difference. The 6.8kW resistor got so hot it burnt. I used a signal generator to try to locate any shorts and couldn’t find any. I wasn’t sure if I had made a mistake so I thought I would build the other kit to see if it would do the same thing. I assembled the second amplifier, checking every resistor value just in case. I left out D4 and D5 because they’re not really needed and I only put in Q10 and Q11 just to make it easier to test. I predicted that the second amplifier would do the same as the first because I am pretty confident in my construction ability. Not to my surprise, this second amplifier went full negative rail on the output as well. I had two other people help me fault-find, who are a bit more experienced at fault-finding than me. At first look at the circuit, I got the comment that the resistor values around Q4, Q5 and Q6 were rather low values but I was told it probably doesn’t really matter. We disconnected the 22kW feedback resistor and grounded it and then we grounded the two 100W resistors on the base of Q8 and Q9. We powered the circuit up to only 20V on the rails because I was worried that if we put the power up too full, it would burn the 6.8kW resistor again. Q2, Q3 and Q1 all seemed to work OK. We then checked Q4 and Q5 and they seemed to be saturated. Q6 was also drawing a lot of current. We rewired the circuit back to normal and re-powered the circuit to 20V again. We experimented with increasing the value of the 100W resistor connected between the 70V rail and D3. This started to have an effect on the output. VR2 did not seem to have any effect. We ended up changing the 100W resistor between VR2 and Q7’s base to 470W. This then had some sort of desired effect. I then had an output offset of about 2V which could not be improved using VR1. Then I fed a sinewave from a signal generator to the input and observed the output. VR2 had an effect in removing crossover distortion. The output signal was about 40V peak-peak. This was with the 470W 10W resistors in place of the fuses, so I expected the output voltage to be a bit low because of voltage drop across the resistors. The sinewave on the output was slightly distorted. Since then, I have not bothered with any further experimenting. Could you please give me some feedback on how you might think I could resolve this problem? (M. T., via email). • What possessed you to start making wholesale changes to the circuit? You should not be making any changes. Hundreds of this amplifier have been built without any problems and we have used this general circuit configuration for over 20 years. In other words, if your amplifier does not work, assume that you have a fault, not a design problem! The fact that Q4 & Q5 are saturating indicates that the problem is in the early stages, possibly involving Q2 & Q3. Have you measured the voltages there? We suspect you might have the wrong transistors installed for Q1, Q2 & Q3 or possibly they are wrongly connected. Q6 should not be drawing high current although it might be getting hot. Again, have you measured the voltages around it? March 2006  105 Upgrading The 15W Class-A Amplifier I have just finished your 15W Class-A Amplifier (SILICON CHIP, (July & August 1998), as sold by Altronics. It sounds great but I would like to upgrade the output capacitors. Would this be possible? Also I would like to increase the bass a little. Any ideas on how I could do this? (R. M., via email). • There are no output capacitors as such, since like most semiconductor power amplifiers, this is a direct-coupled design. The only capacitor in the output stage is the 150nF unit in the output filter and this is a metallised polyester type so there is no point in changing it explosively and can cause injury to anyone in too close proximity. Then again, how would you predict how the patient was going to fall and how would you decide how the airbag(s) should be positioned and activated to cushion the fall? Detecting the fall would also be very difficult since it could be in any direction and may happen very quickly or in “slow motion”. Again, if the fall is slow, the airbag might be activated before it could be of use. Maybe some sort of padded suit would be a better proposition. In fact, maybe airbag technology could be used to pressurise the suit when a fall was detected. It is an interesting idea but we do not have any experience in this area. Digital slave flash trigger I am currently assembling the Digital Slave Flash Trigger (SILICON CHIP, July 2003). One small problem was the hot running of Q2. As it turned out, it is essential to turn one of the switches to the “on” position to prevent full voltage being present on the output of IC2b. The circuit works well (it is still on the bench without its casing) with a single flash but is erratic when I put the camera on “anti-red eye”. In that setting, it puts out many flashes, six I guess, and then two main flashes and the reaction of the unit becomes very 106  Silicon Chip for something supposedly better. This is still the best-performing amplifier we have ever described and no design published anywhere else can touch it. You cannot really improve the bass response since it is already virtually flat to below 10Hz. Nor can you afford to apply much bass boost since that can rapidly run the amplifier into overload at quite modest power outputs. If your system really is bass deficient, you can try placing the speakers closer to the walls or corners (tends to muddy the sound quality) or upgrade the speakers themselves. unpredictable and sometimes I get the impression it is still counting on from the previous set of flashes. Either that or the inconsistency is caused by the photodiode not being sensitive enough and just picking up a signal here and there. (C. B., via email). • From your description of the way your Slave Flash Trigger is “misbehaving”, we suspect this may be due to it being uncased. This will reduce the effective output pulse level from the photodiode, because of the somewhat higher ambient light level. We suggest that you fit the board assembly in the box and also place the lid on temporarily. Then try its operation again and it’s likely that it will behave more predictably. Note that it is necessary to have at least one of the DIP switches (D1-D5) set, because otherwise the counter (IC1) cannot count pulses and trigger the slave flash. If your camera provides, say, six brief pre-flashes and two main flashes in “anti red-eye” mode, you’d need to set the switches to count eight pulses, so the slave slash is triggered only on the second main flash from the camera. Remote sensor for the bilge sniffer I wish to build the Bilge Sniffer (SILICON CHIP, September 2005) but would prefer to have the hydrocarbon gas sensor mounted remotely in the underfloor area of a ski boat. The PC board would be up on the instrument panel for waterproofing and monitoring/control purposes. Is there is any reason why the sensor cannot be mounted remotely from the PC board? (D. B., via email). • The sensor can be mounted remotely. You can use a twin shielded cable to do this, with one side for the 5V supply and other for the signal. Command control is now obsolete Back in January 1998 you did a Command Control project for model trains. Are the parts still available and if so, where can I obtain them? Also, did you revisit that project with a revamp? (R. M., McLaren Vale, SA). • The ZN409CE used in the decoder modules would now be very difficult to obtain. In any case, you would probably be better off considering a changeover to a DCC system as the modules are now relatively cheap. Electrical storm damage to a computer I’m writing with an enquiry about my computer and the possibility that faulty electrical wiring behind the power point into which is was plugged into, contributed to it being damaged in an electrical storm. There was no surge protector on my computer – that is my fault and I was fully prepared to get a new computer, because I did not have a protector on it. But then I found that the other computer in the house was also plugged in during the storm and was not damaged. I am now wondering if my computer was damaged because it was plugged into a faulty socket. If this is the case, I feel it might be the landlord’s responsibility to get me a new computer. When you move a cable that’s plugged into the power point, the power flickers on and off. When I plugged a powerboard into it, I did notice that the light indicating the power supply was flickering. I hope you can give me some advice. (K. W., via email). • Even if your power point is faulty, it is not likely to have caused damage to your computer. It is possible to have perfectly sound wiring and have just one appliance damaged during a storm. Computers are particularly siliconchip.com.au vulnerable because they are usually hooked up to the power and also to the phone system via a modem which means they get a double-whammy. Surge protectors can help but the only sure way to ensure no damage occurs during a thunderstorm is to completely disconnect your computer; ie, don’t just switch it off at the wall – unplug it as well. The same caution applies to other mains-powered appliances. Lightning can kill any appliance, regardless of how much surge protection may be in place. If you have contents insurance, you may be able to claim for the damage. Head-up display for a car Would you have any plans for a Heads-Up Display for vehicles? It would seem to be only a small modification to your digital speedo project a while ago, just reversed. It would be an excellent safety modification kit that would appeal to many people. (D. W., via email). • We do not have any plans – it would be a huge job, including the installation of a display projection unit. SCART interface cable wanted I am hoping that you can advise me on a way to feed a signal from my new set-top box to my VCR. My new Samsung Digital Set-top Box/DVD player has a SCART jack and a SCART/RGB cable to enable connection to a VCR. My reasonably new Panasonic VCR (NV-SJ 230) does not have RGB jacks. It has only a coax Notes & Errata Mixture Display, Electronic Projects for Cars, Vol.2: the text on page 46 does not agree with the circuit and PC board component diagram which shows two red LEDs for rich mixtures and two yellow LEDs for lean mixtures. Since lean mixtures can damage a motor, the red and yellow LEDs should be swapped so that red LEDs indicate a lean mixture while yellow LEDs indicate a rich mixture. jack and two (white and yellow from memory) jacks. Is there such a thing as a SCART/ COAX converter cable? If so, who makes it? If not, can you think of a way to feed a signal from the set-top box into the VCR? (P. H., via email). • Pin 19 of the SCART socket on your STB is composite video out. You can purchase SCART to RCA socket adaptors to let you connect your VCR. For example, Dick Smith Electronics have a SCART multi-adaptor at $23.96; Cat. L-0023. If your VCR has S-video inputs, you can also get a SCART to S-video cable. Powering five 20W amplifier kits I have five 20W amplifier modules and would like to know what is the best and cheapest way to power all five if they are all going to be in the one box. The kit instructions refer to the SC480’s power supply and it mentions that it is only powerful enough iPOD Charger, February 2006: with some iPOD models (eg, the iPOD Video), charging will not initiate when connected to the iPOD Charger. The remedy is to solder a 1kW 0.25W resistor between pins 2 and 3 of the USB socket on the iPOD Charger. In this way, the iPOD will recognise that the iPOD Charger has been connected. The resistor can be directly soldered to the pins of the USB socket beneath the PC board. to power two amplifier kits. There is a 100W amplifier (the SC480) that is powered by the same supply. Would I be able to use it to power my five 20W amplifiers? (D. B., via email). • We assume your amplifiers are based on the 20W Schoolies Amplifier, as described in December 2004. You’ll need a 150VA transformer or better, to power all five modules. The SC480 power supply is not up to the job, as a higher total current is required at the lower supply rails required by these amplifiers. However, a suitable power supply can be constructed from readily available parts. A pair of 10,000mF 50V capacitors (Altronics R-5601) and a 10A metal bridge rectifier (Altronics Z-0088) would do the job. The capacitors can be conveniently installed on the K-3010 mounting board, while the bridge rectifier should be bolted to a metal panel for cooling. Use heavyduty hook-up wire to connect it all together and keep the wires to the SC rectifier as short as possible. WARNING! SILICON CHIP magazine regularly describes projects which employ a mains power supply or produce high voltage. All such projects should be considered dangerous or even lethal if not used safely. Readers are warned that high voltage wiring should be carried out according to the instructions in the articles. When working on these projects use extreme care to ensure that you do not accidentally come into contact with mains AC voltages or high voltage DC. If you are not confident about working with projects employing mains voltages or other high voltages, you are advised not to attempt work on them. Silicon Chip Publications Pty Ltd disclaims any liability for damages should anyone be killed or injured while working on a project or circuit described in any issue of SILICON CHIP magazine. Devices or circuits described in SILICON CHIP may be covered by patents. SILICON CHIP disclaims any liability for the infringement of such patents by the manufacturing or selling of any such equipment. SILICON CHIP also disclaims any liability for projects which are used in such a way as to infringe relevant government regulations and by-laws. Advertisers are warned that they are responsible for the content of all advertisements and that they must conform to the Trade Practices Act 1974 or as subsequently amended and to any governmental regulations which are applicable. siliconchip.com.au March 2006  107 ALL S ILICON C HIP SUBSCRIBERS – PRINT, OR BOTH – AUTOMATICALLY QUALIFY FOR A REFERENCE $ave 10%ONLINE DISCOUNT ON ALL BOOK OR PARTSHOP PURCHASES. CHIP BOOKSHOP 10% (Does not apply to subscriptions) SILICON For the latest titles and information, please refer to our website books page: www.siliconchip.com.au/Shop/Books PIC MICROCONTROLLERS: know it all SELF ON AUDIO Multiple authors $85.00 The best of subjects Newnes authors have written over the past few years, combined in a one-stop maxi reference. Covers introduction to PICs and their programming in Assembly, PICBASIC, MBASIC & C. 900+ pages. PROGRAMMING and CUSTOMIZING THE PICAXE By David Lincoln (2nd Ed, 2011) $65.00* A great aid when wrestling with applications for the PICAXE See series of microcontrollers, at beginner, intermediate and Review April advanced levels. Every electronics class, school and library should have a copy, along with anyone who works with PICAXEs. 300 pages in paperback. 2011 PIC IN PRACTICE by D W Smith. 2nd Edition - published 2006 $60.00* Based on popular short courses on the PIC, for professionals, students and teachers. Can be used at a variety of levels. An ideal introduction to the world of microcontrollers. 255 pages in paperback. PIC MICROCONTROLLER – your personal introductory course By John Morton 3rd edition 2005. $60.00* A unique and practical guide to getting up and running with the PIC. It assumes no knowledge of microcontrollers – ideal introduction for students, teachers, technicians and electronics enthusiasts. Revised 3rd edition focuses entirely on re-programmable flash PICs such as 16F54, 16F84 12F508 and 12F675. 226 pages in paperback. by Douglas Self 2nd Edition 2006 $69.00* A collection of 35 classic magazine articles offering a dependable methodology for designing audio power amplifiers to improve performance at every point without significantly increasing cost. Includes compressors/limiters, hybrid bipolar/FET amps, electronic switching and more. 467 pages in paperback. SMALL SIGNAL AUDIO DESIGN By Douglas Self – First Edition 2010 $95.00* The latest from the Guru of audio. Explains audio concepts in easy-to-understand language with plenty of examples and reasoning. Inspiration for audio designers, superb background for audio enthusiasts and especially where it comes to component peculiarities and limitations. Expensive? Yes. Value for money? YES! Highly recommended. 558 pages in paperback. AUDIO POWER AMPLIFIER DESIGN HANDBOOK by Douglas Self – 5th Edition 2009 $85.00* "The Bible" on audio power amplifiers. Many revisions and updates to the previous edition and now has an extra three chapters covering Class XD, Power Amp Input Systems and Input Processing and Auxiliarly Subsystems. Not cheap and not a book for the beginner but if you want the best reference on Audio Power Amps, you want this one! 463 pages in paperback. DVD PLAYERS AND DRIVES by K.F. Ibrahim. Published 2003. $71.00* OP AMPS FOR EVERYONE By Bruce Carter – 4th Edition 2013 $83.00* This is the bible for anyone designing op amp circuits and you don't have to be an engineer to get the most out of it. It is written in simple language but gives lots of in-depth info, bridging the gap between the theoretical and the practical. 281 pages, A guide to DVD technology and applications, with particular focus on design issues and pitfalls, maintenance and repair. Ideal for engineers, technicians, students of consumer electronics and sales and installation staff. 319 pages in paperback. by Sanjaya Maniktala, Published April 2012. $83.00 Thoroughly revised! The most comprehensive study available of theoretical and practical aspects of controlling and measuring EMI in switching power supplies. Subtitled Exploring the PIC32, a Microchip insider tells all on this powerful PIC! Focuses on examples and exercises that show how to solve common, real-world design problems quickly. Includes handy checklists. FREE CD-ROM includes source code in C, the Microchip C30 compiler, and MPLAB SIM. 400 pages paperback. By Garry Cratt – Latest (7th) Edition 2008 $49.00 Written in Australia, for Australian conditions by one of Australia's foremost satellite TV experts. If there is anything you wanted to know about setting up a satellite TV system, (including what you can't do!) it's sure to be covered in this 176-page paperback book. See Review Feb 2004 SWITCHING POWER SUPPLIES A-Z PROGRAMMING 32-bit MICROCONTROLLERS IN C By Luci di Jasio (2008) $79.00* PRACTICAL GUIDE TO SATELLITE TV See Review March 2010 ELECTRIC MOTORS AND DRIVES By Austin Hughes & Bill Drury - 4th edition 2013 $59.00* This is a very easy to read book with very little mathematics or formulas. It covers the basics of all the main motor types, DC permanent magnet and wound field, AC induction and steppers and gives a very good description of how speed control circuits work with these motors. Soft covers, 444 pages. NEWNES GUIDE TO TV & VIDEO TECHNOLOGY By KF Ibrahim 4th Edition (Published 2007) $49.00 It's back! Provides a full and comprehensive coverage of video and television technology including HDTV and DVD. Starts with fundamentals so is ideal for students but covers in-depth technologies such as Blu-ray, DLP, Digital TV, etc so is also perfect for engineers. 600+ pages in paperback. RF CIRCUIT DESIGN by Chris Bowick, Second Edition, 2008. $63.00* The classic RF circuit design book. RF circuit design is now more important that ever in the wireless world. In most of the wireless devices that we use there is an RF component – this book tells how to design and integrate in a very practical fashion. 244 pages in paperback. PRACTICAL RF HANDBOOK AC MACHINES By Jim Lowe Published 2006 $66.00* Applicable to Australian trades-level courses including NE10 AC Machines, NE12 Synchronous Machines and the AC part of NE30 Electric Motor Control and Protection. Covering polyphase induction motors, singlephase motors, synchronous machines and polyphase motor starting. 160 pages in paperback. PRACTICAL VARIABLE SPEED DRIVES & POWER ELECTRONICS Se e by Malcolm Barnes. 1st Ed, Feb 2003. $73.00* Review An essential reference for engineers and anyone who wishes to design or use variable speed drives for induction motors. 286 pages in soft cover. Feb 2003 BUILD YOUR OWN ELECTRIC MOTORCYCLE by Carl Vogel. Published 2009. $40.00* by Ian Hickman. 4th edition 2007 $61.00* Alternative fuel expert Carl Vogel gives you a hands-on guide with A guide to RF design for engineers, technicians, students and enthusiasts. the latest technical information and easy-to-follow instructions Covers key topics in RF: analog design principles, transmission lines, for building a two-wheeled electric vehicle – from a streamlined couplers, transformers, amplifiers, oscillators, modulation, transmitters and scooter to a full-sized motorcycle. 384 pages in soft cover. receivers, propagation and antennas. 279 pages in paperback. *NOTE: ALL PRICES ARE PLUS P&P – AUSTRALIA ONLY: $10.00 per order; NZ – $AU12.00 PER BOOK; REST OF WORLD $AU18.00 PER BOOK To Place Your Order: INTERNET (24/7) PAYPAL (24/7) eMAIL (24/7) www.siliconchip. com.au/Shop/Books Use your PayPal account silicon<at>siliconchip.com.au silicon<at>siliconchip.com.au with order & credit card details FAX (24/7) MAIL (24/7) Your order and card details to Your order to PO Box 139 Collaroy NSW 2097 (02) 9939 2648 with all details PHONE – (9-5, Mon-Fri) Call (02) 9939 3295 with with order & credit card details You can also order and pay for books by cheque/money order (Mail Only). Make cheques payable to Silicon Chip Publications. ALL TITLES SUBJECT TO AVAILABILITY. PRICES VALID FOR MONTH OF MAGAZINE ISSUE ONLY. ALL PRICES INCLUDE GST ALL S ILICON C HIP SUBSCRIBERS – PRINT, OR BOTH – AUTOMATICALLY QUALIFY FOR A REFERENCE $ave 10%ONLINE DISCOUNT ON ALL BOOK OR PARTSHOP PURCHASES. CHIP BOOKSHOP 10% (Does not apply to subscriptions) SILICON For the latest titles and information, please refer to our website books page: www.siliconchip.com.au/Shop/Books PIC MICROCONTROLLERS: know it all SELF ON AUDIO Multiple authors $85.00 The best of subjects Newnes authors have written over the past few years, combined in a one-stop maxi reference. Covers introduction to PICs and their programming in Assembly, PICBASIC, MBASIC & C. 900+ pages. PROGRAMMING and CUSTOMIZING THE PICAXE By David Lincoln (2nd Ed, 2011) $65.00* A great aid when wrestling with applications for the PICAXE See series of microcontrollers, at beginner, intermediate and Review April advanced levels. Every electronics class, school and library should have a copy, along with anyone who works with PICAXEs. 300 pages in paperback. 2011 PIC IN PRACTICE by D W Smith. 2nd Edition - published 2006 $60.00* Based on popular short courses on the PIC, for professionals, students and teachers. Can be used at a variety of levels. An ideal introduction to the world of microcontrollers. 255 pages in paperback. PIC MICROCONTROLLER – your personal introductory course By John Morton 3rd edition 2005. $60.00* A unique and practical guide to getting up and running with the PIC. It assumes no knowledge of microcontrollers – ideal introduction for students, teachers, technicians and electronics enthusiasts. Revised 3rd edition focuses entirely on re-programmable flash PICs such as 16F54, 16F84 12F508 and 12F675. 226 pages in paperback. by Douglas Self 2nd Edition 2006 $69.00* A collection of 35 classic magazine articles offering a dependable methodology for designing audio power amplifiers to improve performance at every point without significantly increasing cost. Includes compressors/limiters, hybrid bipolar/FET amps, electronic switching and more. 467 pages in paperback. SMALL SIGNAL AUDIO DESIGN By Douglas Self – First Edition 2010 $95.00* The latest from the Guru of audio. Explains audio concepts in easy-to-understand language with plenty of examples and reasoning. Inspiration for audio designers, superb background for audio enthusiasts and especially where it comes to component peculiarities and limitations. Expensive? Yes. Value for money? YES! Highly recommended. 558 pages in paperback. AUDIO POWER AMPLIFIER DESIGN HANDBOOK by Douglas Self – 5th Edition 2009 $85.00* "The Bible" on audio power amplifiers. Many revisions and updates to the previous edition and now has an extra three chapters covering Class XD, Power Amp Input Systems and Input Processing and Auxiliarly Subsystems. Not cheap and not a book for the beginner but if you want the best reference on Audio Power Amps, you want this one! 463 pages in paperback. DVD PLAYERS AND DRIVES by K.F. Ibrahim. Published 2003. $71.00* OP AMPS FOR EVERYONE By Bruce Carter – 4th Edition 2013 $83.00* This is the bible for anyone designing op amp circuits and you don't have to be an engineer to get the most out of it. It is written in simple language but gives lots of in-depth info, bridging the gap between the theoretical and the practical. 281 pages, A guide to DVD technology and applications, with particular focus on design issues and pitfalls, maintenance and repair. Ideal for engineers, technicians, students of consumer electronics and sales and installation staff. 319 pages in paperback. by Sanjaya Maniktala, Published April 2012. $83.00 Thoroughly revised! The most comprehensive study available of theoretical and practical aspects of controlling and measuring EMI in switching power supplies. Subtitled Exploring the PIC32, a Microchip insider tells all on this powerful PIC! Focuses on examples and exercises that show how to solve common, real-world design problems quickly. Includes handy checklists. FREE CD-ROM includes source code in C, the Microchip C30 compiler, and MPLAB SIM. 400 pages paperback. By Garry Cratt – Latest (7th) Edition 2008 $49.00 Written in Australia, for Australian conditions by one of Australia's foremost satellite TV experts. If there is anything you wanted to know about setting up a satellite TV system, (including what you can't do!) it's sure to be covered in this 176-page paperback book. See Review Feb 2004 SWITCHING POWER SUPPLIES A-Z PROGRAMMING 32-bit MICROCONTROLLERS IN C By Luci di Jasio (2008) $79.00* PRACTICAL GUIDE TO SATELLITE TV See Review March 2010 ELECTRIC MOTORS AND DRIVES By Austin Hughes & Bill Drury - 4th edition 2013 $59.00* This is a very easy to read book with very little mathematics or formulas. It covers the basics of all the main motor types, DC permanent magnet and wound field, AC induction and steppers and gives a very good description of how speed control circuits work with these motors. Soft covers, 444 pages. NEWNES GUIDE TO TV & VIDEO TECHNOLOGY By KF Ibrahim 4th Edition (Published 2007) $49.00 It's back! Provides a full and comprehensive coverage of video and television technology including HDTV and DVD. Starts with fundamentals so is ideal for students but covers in-depth technologies such as Blu-ray, DLP, Digital TV, etc so is also perfect for engineers. 600+ pages in paperback. RF CIRCUIT DESIGN by Chris Bowick, Second Edition, 2008. $63.00* The classic RF circuit design book. RF circuit design is now more important that ever in the wireless world. In most of the wireless devices that we use there is an RF component – this book tells how to design and integrate in a very practical fashion. 244 pages in paperback. PRACTICAL RF HANDBOOK AC MACHINES By Jim Lowe Published 2006 $66.00* Applicable to Australian trades-level courses including NE10 AC Machines, NE12 Synchronous Machines and the AC part of NE30 Electric Motor Control and Protection. Covering polyphase induction motors, singlephase motors, synchronous machines and polyphase motor starting. 160 pages in paperback. PRACTICAL VARIABLE SPEED DRIVES & POWER ELECTRONICS Se e by Malcolm Barnes. 1st Ed, Feb 2003. $73.00* Review An essential reference for engineers and anyone who wishes to design or use variable speed drives for induction motors. 286 pages in soft cover. Feb 2003 BUILD YOUR OWN ELECTRIC MOTORCYCLE by Carl Vogel. Published 2009. $40.00* by Ian Hickman. 4th edition 2007 $61.00* Alternative fuel expert Carl Vogel gives you a hands-on guide with A guide to RF design for engineers, technicians, students and enthusiasts. the latest technical information and easy-to-follow instructions Covers key topics in RF: analog design principles, transmission lines, for building a two-wheeled electric vehicle – from a streamlined couplers, transformers, amplifiers, oscillators, modulation, transmitters and scooter to a full-sized motorcycle. 384 pages in soft cover. receivers, propagation and antennas. 279 pages in paperback. *NOTE: ALL PRICES ARE PLUS P&P – AUSTRALIA ONLY: $10.00 per order; NZ – $AU12.00 PER BOOK; REST OF WORLD $AU18.00 PER BOOK To Place Your Order: INTERNET (24/7) PAYPAL (24/7) eMAIL (24/7) www.siliconchip. com.au/Shop/Books Use your PayPal account silicon<at>siliconchip.com.au silicon<at>siliconchip.com.au with order & credit card details FAX (24/7) MAIL (24/7) Your order and card details to Your order to PO Box 139 Collaroy NSW 2097 (02) 9939 2648 with all details PHONE – (9-5, Mon-Fri) Call (02) 9939 3295 with with order & credit card details You can also order and pay for books by cheque/money order (Mail Only). Make cheques payable to Silicon Chip Publications. ALL TITLES SUBJECT TO AVAILABILITY. PRICES VALID FOR MONTH OF MAGAZINE ISSUE ONLY. ALL PRICES INCLUDE GST MARKET CENTRE Cash in your surplus gear. Advertise it here in Silicon Chip. CLASSIFIED ADVERTISING RATES Advertising rates for this page: Classified ads: $22.00 (incl. GST) for up to 20 words plus 66 cents for each additional word. Display ads: $36.00 (incl. GST) per column centimetre (max. 10cm). Closing date: five weeks prior to month of sale. To run your classified ad, print it clearly on a separate sheet of paper, fill out the form & send it with your cheque or credit card details to: Silicon Chip Classifieds, PO Box 139, Collaroy, NSW 2097. Alternatively, fax the details to (02) 9979 6503 or send an email to silchip<at>siliconchip.com.au  Taxation Invoice ABN 49 003 205 490 Enclosed is my cheque/money order for $­__________ or please debit my o Bankcard   o Visa Card   o Master Card       CLEVERSCOPE USB OSCILLOSCOPES Card No. Signature­­­­­­­­­­­­__________________________ Card expiry date______/______ Name _____________________________________________________ Street _____________________________________________________ Suburb/town ___________________________ Postcode______________ Phone:_____________ Fax:_____________ Email:__________________ FOR SALE LEDs – SUPERBRIGHTS from just 25 cents each. 12 volt LED lightbars and kits, great for solar/camping. New IN14 nixie clock kit available now! Lots of other interesting stuff, if I don’t have it, just ask! www.ledsales.com.au PCBs MADE, ONE OR MANY. Any format, hobbyists welcome. Sesame Electronics Phone (02) 9593 1025. sesame<at>sesame.com.au www.sesame.com.au More control solutions for you! NEW iUSBDaq Data Acquisition Module: features 8 12-bit analog inputs, 16 digital I/O, 2 PWM outputs, 1 high speed counter. High sampling rates. Free software, Labview driver and dll component. N1500LC Load Cell Panel Meter: New 110  Silicon Chip Low Cost, Great Accuracy, Fully programmable Indicator with 4-20mA and 2 relay outputs. USB to RS422/RS485 converter: with 1500V Isolation, RTS or Auto Data Flow control. Heaps of other features. Electronic Thermostats: with digital temperature displays, 2 control relays, can be used in heating and cooling. NTC thermistor or J TC or Pt100 sensors. Temperature and Humidity Sensors: Great accuracy, 4-20mA output. Wall and Duct mounting available. Signal Conditioners non isolated and isolated: convert thermocouples, RTDs to 4-20mA or 0-10V Fully programmable. Stepper Motors: we have a selection of Stepper motors for hobby and high torque CNC applications. DC Motors for both hobby and high torque applications. DC, Stepper and Servo Motor controller kits. 100MSa/s 10bits each channel 4M samples per input 100MHz bandwidth 8 digital inputs Sig-gen option Spectrum analyser Windows 98/Me/NT/2k/XP GRANTRONICS PTY LTD PO Box 275, Wentworthville. 2145. Ph: 02 9896 7150 www.grantronics.com.au Counter and Timers: 7-digit and 10year battery operated. Multi Function Timer and Cyclic Timer/ Pulse Generator Serial and Parallel Port relay controller cards. Pump and Trip Alarm controller card. Duty-Standby operation. PIC MicroProgrammers: serial and USB port operated. 2, 4 & 8 Relay Cards: suitable for TTL and Open Collector Outputs. Switch Mode, Battery Chargers and DC-DC converters. Full details and credit card ordering available at www.oceancontrols.com. au Helping to put you in control. ImageCraft C Compilers: 32-bit Wind­ows IDE and compiler. For AVR, 68HC­ 08, 68HC11, 68HC12, 68HC16. from $330.00 Atmel Flash CPU Programmer: Handles the 89Cx051, 89C5x, 89Sxx in siliconchip.com.au 6 program DVB receiver COMPACT LINE Laceys.tv ™ 42 Brunel Rd Seaford VIC 3198 Tel (03) 9776 9222 web:www.laceys.tv also Sydney, CoffsHarbour, Ulverstone TAIG MACHINERY Micro Mini Lathes and Mills From $489.00 Stepper motors: 200 oz in $89.00, 330 oz in $110.00 Digital verniers: 150mm $55.00, 200mm $65.00 59 Gilmore Crescent (02) 6281 5660 Garran ACT 2605 0412269707 Expert speaker repairs Hi-Fi Professional Car Foam and rubber surrounds, voice coils, spiders, cones and more. Original parts for Dynaudio, Tannoy, EV, JBL and others. Australian agents for Ortofon products. Trade welcome. Email us for your user ID. Phone (03) 9647 7000 www.speakerbits.com Select your microcontroller kit and get started... Fax a copy of both DIP and PLCC44 and some AVR’s, most 8-pin EEPROMS. Includes socket for serial ISP cable. $220, $11 p&p. SOIC adaptors: 20 pin $132.00, 14 pin $126.50, 8 pin $121.00. Full details on web-site. Credit cards accepted. GRANTRONICS PTY LTD, PO Box 275, Wentworthville 2145. (02) 9896 7150 or http://www.grantronics. com.au WE LOVE OUR ELECTRONICS. We have many interesting things to do. And we have a part-time position available. Hand soldering, prototyping, design and more. Penrith, NSW. email michael<at> furzy.com LTM10C036 10.4” Colour TFT LCD Kit qty 5 (Sk2009R kit). NL10276AC24-02 12.1” Colour TFT LCD Kit qty 1 (Sk2005R kit) 12-volt, siliconchip.com.au From $295* RCM3400 this ad and receive a 5% discount on your order! Feature rich, compiler, editor & debugger with royalty free TCP/IP stack • Prices exclude GST and delivery charges. Tel: + 61 2 9906 6988 Fax: + 61 2 9906 7145 www.dominion.net.au DB15HD interface, $150 each (typically US$380). LQ9D03B 8.4” Colour TFT LCD only qty 3 $100. Bought from earthlcd.com. peter.baxter <at>tantau.com.au S-Video . . . Video . . . Audio . . . VGA distribution amps, splitters, standards 4007 converters, tbc’s, switchers, cables, etc, & price list: www.questronix.com.au RCS RADIO/DESIGN is at 41 Arlewis St, Chester Hill 2162, NSW Australia and has all the published PC boards from SC, EA, ETI, HE, AEM & others. Ph (02) 9738 0330. sales<at>rcsradio. com.au, www.rcsradio.com.au March 2006  111 Do You Eat, Breathe and Sleep TECHNOLOGY? Opportunities for full-time and part-time positions all over Australia & New Zealand Jaycar Electronics is a rapidly growing, Australian owned, international retailer with more than 39 stores in Australia and New Zealand. Our aggressive expansion programme has resulted in the need for dedicated individuals to join our team to assist us in achieving our goals. We pride ourselves on the technical knowledge of our staff. Do you think that the following statements describe you? Please put a tick in the boxes that do: Knowledge of electronics, particularly at component level. Assemble projects or kits yourself for car, computer, audio, etc. Have empathy with others who have the same interest as you. May have worked in some retail already (not obligatory). Have energy, enthusiasm and a personality that enjoys helping people. Appreciates an opportunity for future advancement. Have an eye for detail. Why not do something you love and get paid for it? Please write or email us with your details, along with your C.V. and any qualifications you may have. We pay a competitive salary, sales commissions and have great benefits like a liberal staff purchase policy. Send to: Retail Operations Manager - Jaycar Electronics Pty Ltd P.O. Box 6424 Silverwater NSW 1811 Email: jobs<at>jaycar.com.au Jaycar Electronics is an equal opportunity employer and actively promotes staff from within the organisation. Satellite TV Reception Best high end DIY audio kits on the planet! www.aksaonline.com Importer Direct Sale International satellite TV reception in your home is now affordable. Send for your free info pack containing equipment catalog, satellite lists, etc or call for appointment to view. We can display all satellites from 76.5° to 180°. AV-COMM P/L, 24/9 Powells Rd, Brookvale, NSW 2100. Tel: 02 9939 4377 or 9939 4378. Fax: 9939 4376; www.avcomm.com.au DISTRIBUTORS pty. ltd. ACN 008 801 161 ABN 84 177 396 871 New American technology, polycrystalline solar panels, super long service life, high-efficiency output, compact and light, just 34 x 36cm and 1.58kg. Full weather-proof aluminium frame and tempered glass. Rated 10W, 12V, 0.82A; can charge 12V battery in virtually any climate. Brand new, limited stock. $159. Free post delivery. Ausino Pty Ltd, 129 Mcewan Rd, Heidelberg West, Vic 3081. Tel: (03) 9459 6011; Email: ausino99<at>optusnet.com.au INTERNAL SALES REPRESENTATIVE The successful applicant will be bright, self motivated and well presented with a sound knowledge of electronic components. Industry experience is preferred but not essential. Excellent communication, organisation and customer service skills are essential. Apply in writing to: Personnel Manager PO Box 8350 Perth Business Centre, W.A. 6849. or via email to: dean.stephens<at>altronics.com.au You have the Circuit - We can Package it? Printed Circuit Boards - Call Mike for PCB Layout Prototyping, Small Runs and Production Runs Product & Panel Labelling - Call Martin for Full Colour on Clear, White, Brushed Aluminium, or Gold Label. Resources Mi M ar FACTORY 3 / 26 STAFFORD STREET HUNTINGDALE 3166 Tel: (03) 9 562 7030 Fax: (03) 9 562 7040 e-mail: pcbs<at>alphalink.com.au WEATHER STATIONS: windspeed & direction, inside temperature, outside temperature and windchill. Records highs and lows with time and date as they occur. Optional rainfall and PC interface. Used by government departments, farmers, pilots and weather enthusiasts. Other models with barometric pressure, humidity, dew point, solar radiation, UV, leaf wetness, etc. Just phone, fax or write for our FREE catalog and price list. Eco Watch: phone (03) 9761 7040; fax (03) 112  Silicon Chip 9761 7050; Unit 5, 17 Southfork Drive, Kilsyth, Victoria 3137. ABN 63 006 399 480. WANTED WANTED: EARLY HIFIs, AMPLIFIERS, Speakers, Turntables, Valves, Books, Quad, Leak, Pye, Lowther, Ortofon, SME, Western Electric, Altec, Marantz, McIntosh, Goodmans, Wharfedale, Tannoy, radio and wireless. Collector/ Hobbyist will pay cash. (07) 5471 1062. johnmurt<at>highprofile.com.au Advertising Index 555 Electronics.............................15 Alternative Technology Assoc....101 Altronics.....................................112 Amateur Scientist CDs...............IBC Aspen Amplifiers........................112 Ausino Pty Ltd............................112 Av-Comm...................................112 BitScope Designs.........................37 Dick Smith Electronics........... 24-29 Digital Graphics..........................111 Dominion Electronics............79,111 Eco Watch..................................112 Elexol...........................................51 Evatco........................................101 FreeNet Antennas......................111 Furzy Electronics........................110 Futurlec........................................51 Grantronics.................................110 Harbuch Electronics.....................63 Instant PCBs..............................112 Jaycar ..................IFC,53-60,62,112 JED Microprocessors................5,62 Laceys TV..................................111 Microbric......................................69 Microgram Computers....................3 MicroZed Computers....................49 MiMar Resources.......................112 Oatley Electronics........................97 Ocean Controls..........................110 Quest Electronics..................62,111 Radio Parts..............................OBC RCS Radio.................................111 RF Modules..................................62 SC Perform. Elect. For Cars.........19 Silicon Chip Bookshop....... 108-109 Silicon Chip Subscriptions....23,103 Silvertone Electronics................111 Siomar Batteries..........................83 Speakerbits................................111 Taig Machinery...........................111 Telelink....................................62,83 Trio...............................................21 KIT ASSEMBLY NEVILLE WALKER KIT ASSEMBLY & REPAIR: • Australia wide service • Small production runs • Specialist “one-off” applications Phone Neville Walker (07) 3857 2752 Email: flashdog<at>optusnet.com.au siliconchip.com.au