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PRODUCT SHOWCASE Kenwood’s TS-950SDX HF transceiver Kenwood’s TS-950SDX is the company’s flagship wideband HF communications transceiver, designed for all modes of transmission and recep­tion including SSB, CW, AM, FSK and FM on the 10 12, 15, 17, 20, 30, 40, 80 and 160 metre bands. The TS-950SDX incorporates DSP (digital signal processing) circuitry that assists in the modulation and filtering stages. Traditional RC circuits and analog ICs are replaced with digital circuitry that assists the suppression of unwanted sidebands. Up to 15 low pass filters are selectable Power line monitor from Westinghouse The PQM-1000 power monitor is programmed to log the 15 most common types of mains line disturbances. This is done using volt­age and frequency thresholds that are applicable for malfunctions and data corruption in sensitive elec­tronic, industrial controls and com­puter systems. A 2-line liquid crystal display provides a readout of line voltage and frequency, high frequency noise (L-E & N-E) and disturbance event counts. The battery backed memory holds data during pro­ longed power failures. LED indicators are provided to show 90  Silicon Chip in SSB and CW modes with cut off frequencies ranging from 600Hz to 6kHz. In FSK mode, three bandpass filters are selectable with the centre frequency of 2200Hz. Band selection is made by use of 10 direct band/keys that select any one of the amateur bands. When this fea­ture is used in conjunction with the ENT key and Kenwood’s Quick Memory feature, up to five of the most used channels are stacked for quick reference. In addition, another 100 memories are reserved for most used channels. Kenwood claims that the TS950SDX has unprecedented frequency stability and resolution due to its temperature compensated crystal oscillator and microprocessor controlled PLL and DDS circuits. The TS-950SDX also offers a dual-frequency receive facility which allows two frequencies to be received simultaneously. An RX-SUB key allows instant swapping between the two frequencies. A TF-W key is particularly useful for monitoring the transmit frequency. With external speakers or headphones, main and sub receivers can be monitored simultaneously. The TS-950SDX wideband trans­ ceiver has a recommended retail price of $6990 and is available at selected Kenwood dealers. For further information on the TS-950SDX and other Kenwood products, contact Kenwood on (02) 746 1888. New factory for Harbuch Electronics Harbuch Electronics Pty Ltd, makers of power, toroidal and audio transformers, now have a new manufacturing facility at 9/40 Leighton Place, Hornsby. Harbuch has been involved in the design and manufacture of conventional audio and power transformers the occurrence of past or present disturbances. The 15 power disturbance event counters log power failures, voltage drop (sags), low line voltage (brownouts), voltage surges, high line voltages (over voltage), voltage spikes (impulses), high frequency noise and high/low line frequency. Two keys enable the user to scroll up or down through the different displays and event counts. Both keys are pressed at the same time to clear the event counters. For further information, contact John Thompson, Westinghouse Industrial Products, 59 Stephenson St, Spotswood, Vic 3015. Phone (03) 391 1300. for over fifteen years. Increased demand for toroidal transformers has led to the requirement for larger and more efficient premises. A comprehensive stock of most standard items means that overnight delivery is available within Australia. The ability to quickly produce custom designs is a special service, with quotations and full specifications available within 24 hours of request. Steven Whitaker, sales manager for Harbuch, is confi­ dent that the company is now better equipped to re­spond to individual customer requirements. The com­pany is currently undertaking an in depth review of quality assurance procedures in order to achieve Australian Standards Accreditations in the near future. For more information about the products and services offered by Harbuch Electronics phone (02) 476 5854. High density DC/DC converters Computer Products Inc has announced a new series of medium power, high density converters. Designated BASiX, the new converters use a patented Resonant Transition Zero Voltage Switching technique that cuts losses to yield higher efficiency, to offer a high perform­ ance unit with a power density of 36 watt/in3. BASiX provides internal input and output filtering, protection features, true current sharing, redundancy and a 40-amp output capability, all contained in the industry standard 4.6 x 2.4 x 0.5-inch package. There is a choice of input voltage of 40-60V or 36-75V DC. Output voltages are either 3, 5, 12, 15, 24 or 48V DC, and power outputs range from 130W to 200W. The new converters have a constant 700kHz switch­ing frequency for easier system filtering, advanced aver­age current-mode secondary side control, and an inter­nal EMI filter. For further information, contact Amtex Electronics, 13 Avon Road, North Ryde, NSW 2113. Phone (02) 805 2113. New Tektronix scope has colour display Tektronix has announced its newest and lowest priced colour digital oscilloscope, the TDS 524A. It includes the same graphical user interface (GUI), acquisition proc­ess, triggering section and analysis as the recently intro­duced colour TDS 544A. The TDS 524A includes the Tektronix proprietary October 1993  91 Surround sound speakers from Dali Dali has announced the availability of two surround-sound speakers for home theatre systems. The Dali CS-1 is a slim, compact centre channel speaker using high quality drivers. The speakers are magnetically shielded, allowing close placement to a television set without affecting picture quality. The twin 10cm bass/midrange drivers feature polypropylene cones while the 25mm tweeter from Vifa features ferro-fluid oil cooling and mu-metal magnetic shielding. The NuColor full-colour monitor, 500MHz analog bandwidth, 500 megasamples/ second maximum sample rate, up to 50,000 points-per-channel record length (15,000 points standard) and two channel plus two auxiliary channel input. The scope includes a 1.44MB floppy disc drive, an optional video trigger with HDTV triggering, FFT with averaging, and expanded template compact dimensions of 125 x 430 x 180mm (H x W x D) enable the speaker to fit easily above or below the television set. Retail price for the CS-1 is $299 per pair. The Dali-SAT is a compact satellite with two drivers. It has “ball and socket” mounting, allowing the speaker to be tilted and turned to suit individual rooms and systems. Available in both black and white finishes, Dali-SAT retails for $299 per pair. For further information, contact Scan Audio Pty Ltd, 52 Crown St, Richmond, Vic 3121. Phone (03) 429 2199. testing to include maths waveforms. For fur­ther information on the Tektronix col­our and new monochrome TDS oscil­loscopes, phone Tektronix on (02) 888 7066. 20-bit process control engine board Boston Technology Pty Ltd has announced the release of the LLAD 57 VIDEO & TV SERVICE PERSONNEL TV & VIDEO FAULT LIBRARIES AVAILABLE AS PRINTED MANUALS $90 EACH + $10 DELIVERY BOTH MANUALS VIDEO & TV $155 + $15 DELIVERY OR AS A PROGRAM FOR IBM COMPATIBLES $155 + $10 DELIVERY FOR MORE INFORMATION CONTACT TECHNICAL APPLICATIONS FAX / PHONE (07) 378 1064 PO BOX 137 KENMORE 4069 92  Silicon Chip 20-bit process control board for PCs and compatibles. The LLAD 57 is a multi-function board for process applications built around a high-precision temperature-stabilised bridge. It is optimised for weighing applications but is adapt able to a wide range of uses. The board’s circuitry has been specially designed to withstand corrosive industrial environments, and optical iso­lation prevents various functions from interacting even under fault condi­tions. Among the LLAD 57’s features are four isolated 24-240VAC/DC inputs, four 24-230VAC relay outputs, 16 TTL-level digital inputs, 16 digital outputs, one isolated 4-20mA current-loop analog input with programma­ b le speed, and linearity of 0.1% full scale. Comprehensive software is pro­vided for use with the board. For further information, contact Boston Technology Pty Ltd, PO Box 1750, North Sydney, NSW 2059. Digital Power Meter from Yokogawa Yokogawa has announced the release of their new 3-phase 2533E Digital Power Meter for R&D, industrial and production applications. The 2533E uses a 16-bit pulse width modulation technique to measure DC and AC voltage, current and power to an accuracy of up to 0.1% in single phase, 3-phase 3-wire and 3-phase 4-wire power circuits. Offering a frequency response of 30Hz to 30kHz as well as DC capability, the 2533E is also capable of accurately measuring the power of distorted and inverter waveforms. Three large bright displays simultaneously show any three values of measured or computed data. These can include, for example, voltage, cur­rent, power per phase, total power, apparent power and power factor. As well, the 2533E provides 12 analog output signals for connection to auxiliary instruments such as recorders and FFT analysers. Several other computation functions are provided, such as mean value of phase or line voltage and mean value of phase current. An integration option is available, allowing meas­urement of amp-hours or watt-hours to an accuracy of ±0.2% + 1 digit up to a period of 999 hours. A further op­tion allows frequency measurement over the range of 20Hz to 200kHz with an accuracy of ±0.1 % + 1 digit. GPIB and RS232C options are provided, allowing the 2533E to be re­motely controlled and output data to be transferred to a PC. For further information, contact Tony Richardson, Yokogawa Australia Pty Ltd, Centrecourt D3, 25-27 Paul St North, North Ryde, NSW 2113. Phone (02) 805 0699. Economy soldering irons from Scope Two new low cost 25W and 40W utility irons for electronic work have been released by Scope Laboratories. These mains voltage irons feature long-life iron-plated tips that operate at around 380°C, a stainless steel barrel, a non-rolling impact-resistant handle and four tip shapes. For further information, contact Scope Laboratories by phone on (03) 338 1566. LS621 Loudspeakers – continued from page 28 are unable to verify this claim although the response is quite smooth overall. At the bass end there is usable response down to below 45Hz although if pushed hard, the woofer does tend to frequency double. At the high end, the tweet­er is a little prominent in the region of 7- 8kHz and then tapers off a little above that although it is smooth right to the limits of audibility. Efficiency is quoted as 87.5dB at one watt and one metre and the unit is claimed to be suitable for amplifiers rated from 15 watts to 150 watts. Our impressions were that you would need an amplifier of at least 40 to 50 watts and that anything much over 100 watts on program would be too much. That is backed up by the stated maximum SPL (sound pressure level) of 106dB. On music, the Magnet LS-621s give a good account of them­selves although the tweeter seems a little muted for our tastes. We found that they sound rather better with the grille cloth frames off and we think most people would listen to them in this way. On voice, they sound very natural without any tendency to chestiness or emphasis of sibilants. Our overall impression was that they were very satisfying on classical music, especially chamber works, and they give a good account of themselves on jazz material. If you are a heavy rock fan, you will want bigger guns and it would not be fair to expect them to do the job. Recommended retail price of the Magnet LS-621s is $1150 a pair and they are available from A-One Electronics, 432-434 Kent St, Sydney, NSW 2000. They have recently fitted out a sound lounge and to introduce the Magnets they have them on sale at $950 a pair, so get in quickly. Phone A-One Electronics on (02) 267 4819. (L.D.S.) SC FM Wireless Microphone – continued from page 67 it and set the operating frequency. For this you need an FM radio. Connect the 9V battery and turn on your FM radio. Now tune across the band until the speaker squeals. The frequency on your dial is now the operating frequency of the circuit. Now if you want to adjust the frequency of operation, you reverse the process. Tune your radio to a vacant part of the band. Let’s say this frequency is 99MHz. All you should be get­ting is hiss from the loudspeaker of the radio. Now adjust the slug of coil L1 until you get a continuous squeal from the radio. That’s it, the job is complete. In more detail, the tuning range of the wireless microphone can be adjusted upwards by removing the 1pF capacitor. With this capacitor in circuit, the tuning range of L1 will be in the lower region of the FM band: from This close-up view shows how the on/ off switch is fitted to the end-plate at one end of the tube. below 88MHz to about 102MHz. With the 1pF capacitor in circuit, the tuning range will be from about 95MHz. You have to decide which portion of the band you want your cir­cuit to operate in and then pull the capacitor out or leave it in. You then adjust the slug of L1 as described above. After you have adjusted coil L1 to your satisfaction, move the microphone well away from the radio so that the acoustic feedback squeal and distortion is no longer apparent. You should now be able to speak into the microphone and your voice should come from the radio with clean reproduction. You can now complete the construction of your microphone by wiring up the on-off switch and then installing the board and battery inside the anodised aluminium tube. They are held in place by pieces of foam plastic. The PC board is positioned so that the electret protrudes slightly from the end of the tube, after which the foam plastic windshield is fitted. The slide switch is attached to an endplate with epoxy adhesive and then the end plate itself is glued into the tube with the same epoxy. SC October 1993  93