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SERVICEMAN’S LOG The camera eye Dave Thompson I’ve always loved cameras; the idea of capturing a precise moment in time has always been alluring. Back in the 1970s, as a wee tacker, I had one of those ‘kids’ camera that they sold by the millions. I got it for my birthday one year. I don’t recall which, but I know I was very young and had visions of becoming a photographer. It may well have been one of those “Daisy” branded cameras but I can’t remember exactly now. I know I used to have to buy flash cubes for it, and often I didn’t have them nor the money to buy them, so I made do with bright light when I could. It soon became obvious that I would not be the next darling of the photography circuit with this camera! Of course, one had to take the film (with only 12 exposures from memory – not even a full roll) to a local pharmacy or photo place and pay to get it developed. The problem was that most of the shots were blurred, or out of focus, or just rubbish because I was not a good photographer (the latter was the most likely reason). Still, in my defence, the gear was not the best (I know, an engineer blaming his tools rather than lack of talent!). The lenses in those mass-produced cameras were cheap and nasty, and that didn’t help at all! A few years later, I got a ‘proper’ camera: a single-lens-­ reflex (SLR) type that took 35mm film, which made a huge difference to my photos. For a start, I could actually see what I wanted to look at, and what came out on the film was almost what I was seeing through the viewfinder! No 90 Silicon Chip more parallax errors, foggy views or wasted film; unless you considered my resulting photographs wasted film! I’m sure the clever among you have realised my career goal of being a photographer didn’t develop (yes, I know, a bad pun). But I still have a love of cameras, and as early as the 1980s, I was asking myself why they didn’t take images on some kind of EPROM and digitally store them. Obviously, that was a lame and naïve attempt at thinking about the technology side of it; there was no way a technologically challenged individual like me could figure out how that would work out in the real world. But as we all now know, it is very similar to what they ended up doing. I knew I should have registered a patent! Anyway, despite not ending up as a professional photographer, I have still had a keen interest in cameras all my life. That old Yashica served me well for many years. I bought different lenses for it on my many trips overseas so I could try to take better photos. Digital man Then, all of a sudden, digital cameras were all the rage. And my old SLR with all those lenses was pretty much delegated to the scrap heap. I gave it all to a friend’s daughter who was going to take a photography course that involved Australia's electronics magazine Items Covered This Month • The camera eye • Zoom G2.1u guitar effects unit repair • Fixing the fan controller in a Honda Jazz Dave Thompson runs PC Anytime in Christchurch, NZ. Website: www.pcanytime.co.nz Email: dave<at>pcanytime.co.nz Cartoonist – Louis Decrevel Website: loueee.com developing and dark rooms and all that jazz. She seemed to appreciate it, so I guess it went to a good home. I went overseas in 1997, so at that time I bought a new-­ fangled (for the time) digital camera from a local big-box store before I went. This thing wasn’t cheap. From memory, it was about a grand, and it was a Casio-branded camera with a resolution of 800 × 600 pixels. It took very average photos, especially with me behind the lens. I still have the photos I took with it, and being able to just snap away and delete any dud ones as I went was a revelation for me. No more taking rolls of film to the local pharmacy and being disappointed with the out of focus or terribly composed shots – of course, I was charged for developing all of them. Now I only got to keep the photos I liked, no matter if they were low-res and not very well taken. It made that European trip that much easier. The problem is that it ate batteries like a kid eating cake at a party. And back then, batteries were not cheap. It took four AA cells and chewed through them like thermite through a paper plate. I was lucky to get 30 photos before the dreaded low battery warning. There was no built-in flash and there had to be so much light to get a decent photo it just about required one of those NightSun spotlights; the ones police choppers use to illuminate the scene. Still, it was a revelation, and I could see the writing on the wall that this was the future of photography. From that time on I was a digital camera fan, upgrading that old Casio (which I still have somewhere) to various new models, each more advanced than the last. Each one did me well and are still sitting in a drawer somewhere. Usually, it was an overseas trip that triggered my new camera searches and, while the (high) prices remained pretty much the same, the lenses and photo quality (due to better sensors with progressively higher resolutions) improved greatly. These were still point-and-shoot digital cameras, which suited my portability and lack of ability requirements. While digital SLRs were starting to appear on the shelves, they and their accessories were far out of my price range. Those cameras served me well and I still have most of the photos I took with them, stored on external hard drives or CDs and DVDs. Of course, none of those media will likely give up their data after all this time, with siliconchip.com.au burned CDs and DVDs and hard drives notoriously breaking down and failing. For a long time, I just copied them to new discs every year or so, keeping them refreshed, but my backup routine has fallen behind lately. I must get an external SSD and copy everything I can to it from those media. Moving pictures Then another revelation came along: digital camcorders. They were typically far smaller than their VHS, Super8 or even MiniDV cassette-based cameras. These were easily portable, had reasonable image quality and were not ridiculously expensive. One downside was that screen grabs from the videos were of course low-resolution, until I bought a camera that could take high-res snapshots, even while filming video. I just had to be adept enough to push the photo capture button while operating everything else! I wrote once about repairing one of my camcorders, which started faulting well out of warranty (April 2022 issue; siliconchip.au/Article/15283). The side screen would often not work properly; it was covered in lines and missing bits. Google suggested it was the interconnecting strap, one of those really thin, printed Mylar strap (flexible) PCBs with a push-in connector at either end. The replacement was available surprisingly cheaply from China, so I thought I’d give it a go. It was successful, but those things are really complicated and built so tightly, making them a challenge to work on with my fat fingers. So I hope I don’t have to do such a repair again. I’ve also repaired several SLRs over the years, though mainly mechanical faults from being dropped. Again, they are so compactly constructed, with parts just jammed into them everywhere. All these cameras really are a wonder of engineering and design. My fascination with cameras hasn’t stopped there. A while back, we lost a cat, and a friend offered us a supposedly working trail camera, one of those night-vision, motion triggered ones in full camouflage livery. These things too require many batteries for the days or weeks they might spend tied to a tree. I opened it up to put batteries in it but found that it was rotten inside. Someone had left cells in it and, of course, they leaked and corroded everything in the acid’s (or alkaline’s) Australia's electronics magazine April 2025  91 path. Some tracks on the PCB were almost eaten right through in places, and many of the surface-mount components were just fuzzy globs of corrosion. This thing obviously would not fly at all, and its days of snapping wildlife were over. I recovered the IR LED array from it and biffed the rest. There was nothing else for it but to buy another one. Chinese websites are awash with these cameras, but I bought an American-branded one from Amazon. Of course, it was made in China anyway, but it was of good quality and took very good, high-resolution photos, even in the monochrome night-vision mode. We set it up in areas we had credible reports of our cat being, but all it captured were birds and hedgehogs. We never found that cat. Available light So, the jungle camera sat on the shelf until we suspected someone was coming up our long drive – a brave act considering it is shingle and at night, every step must sound like someone opening one of those plastic cake containers you get from the supermarket. Whoever, or whatever, it was triggered our security lights, so there was definitely something, or someone, there. There had also been a spate of vehicle break-ins in the neighbourhood, so while I felt a bit paranoid about it, I set up the trail camera on one of our fence posts. It was relatively hidden from view, unless someone was scouring for one. At night, it would be almost invisible. For the following few days, I checked the camera, which was relatively easy as it has a small built-in colour screen. With a 64GB microSD card, it can fit a fair few images and videos before needing emptying. It is set with motion detection enabled by default, so no real setup was required, except for setting the resolution of the photos and videos, which would obviously impact the capacity of the card. Scrolling through the images, I could see the usual array of cats passing through, and the odd shuffling hedgehog, but neither of these types of critters usually trigger the security lights. So, there was nothing untoward the first night, albeit some good wildlife shots but not much else. The next night, however, the camera picked up some miscreant carefully coming up our drive to the gate. The Servicing Stories Wanted Do you have any good servicing stories that you would like to share in The Serviceman column in SILICON CHIP? If so, why not send those stories in to us? It doesn’t matter what the story is about as long as it’s in some way related to the electronics or electrical industries, to computers or even to cars and similar. We pay for all contributions published but please note that your material must be original. Send your contribution by email to: editor<at>siliconchip.com.au Please be sure to include your full name and address details. gate is just a rusty old wrought-iron thing I’ve been meaning to change for six years. I even have the replacement, a proper heavy duty motorised unit. But, after buying it, I found I’d need to lay a concrete track for it and because it crosses waste pipes, council consent. I filed it in the too-hard basket and simply put an alarm on the gate itself. This is a simple siren with a magnetically controlled trigger (the magnet goes on the other half of the split gate). If it isn’t present and the alarm is set, it sounds quite a piercing piezo siren. It also has a small keyfob style remote control, so I can arm and disarm it from the house, 30 meters away. So if anyone tried to open the gate, I would know. Jumping over it would require some athleticism and would likely set off the alarm, anyway. There was also an automatic security light, so they’d hopefully be scared off and not come back. The photos, taken a few seconds apart, showed him looking at the gate and alarm, so he obviously wanted to get in. Such is urban life. I called the police and told them, but they really couldn’t care less. If the crims broke in and hurt someone, the cops might be interested, but in burglary itself, not so much it seems. The images were good, especially with the light on him, but the intruder was not identifiable from these pictures. He was wearing dark clothes, gloves and a hoodie, the usual burglars’ fashion du jour. I guess a patrolling rottweiler would be the order of the day. Still, it was a warning that we were not immune and couldn’t let our guard down. I left the camera up for another month, but it didn’t pick up anyone else. Hopefully, the guy thought it was too hard. I only took it down because it failed to switch on one day, and a fresh set of batteries made no difference. I did open it up to have a look, but without any information on the circuit or the components, most of which had the numbers obfuscated, it was just more junk for the bin. It had lasted a reasonable time, but this throwaway consumerism is really not on. One little victory So, I did what any gadget guy would do and bought a better camera. This is on another level again. It is a fraction of the size of the trail cam, takes higher resolution photos, and is solar powered from an array that charges the 92 Silicon Chip Australia's electronics magazine siliconchip.com.au onboard batteries. And it only cost $40! There was a twopack for $65, but this would do me fine. Plus, it is controlled by an app over Bluetooth or WiFi and, using the app, I can swivel the bottom half of the camera, which contains one of the two lenses. One is fixed; one is controllable. It is also motion sensitive, with zones that can be included or excluded from the image, and provides a live feed of what is happening, with an alert to our phones. On top of that, it has night vision, and a microSD card stores the images as well! You can imagine my chagrin when I installed it and it didn’t work! I mean, 40 bucks is 40 bucks, right? I tore it open, as one does, and looked as to what could be the cause. When I say tore it open, I’m not kidding; this thing is sealed shut with clips. There are no screws. It is an outdoor camera, so one would expect seals and weatherproofing, and to be fair, it is very well made and has excellent rubberised hatches and sockets. Our camera will be installed under eaves, so it isn’t that critical; it won’t be out in all weathers, but preventing any condensation or moisture ingress is important. The batteries, two 18650 types, were hard-wired in. I measured them as best I could and typically, for cheaper gear, one appeared to be dead. I cut the links between them and the board and took them both out. One was indeed measuring just 0.3V; the other, 3.5V, a little flat but it should be OK. I hit the low one with my power supply to see if I could kick it into life, but even multiple tries resulted in only 0.7V. I was just wasting time here. I sent out for two spares; I’d replace them both, and they cost the same as the camera! At least they had solder terminals, and it was easy enough to solder them back in. This time, pressing the button resulted in some chimes and a voice saying power on. I measured the output of the little solar panel that came with it and confirmed a nice voltage was being generated, even inside my workshop. I stuck it all back together with sealant and it works brilliantly and is patrolling as we speak. Cameras are such fun! Zoom G2.1u Guitar Effects unit repair On a rainy afternoon, I was ‘bogged down’ trying to write some Arduino code. There were several household jobs I could have been asked to do if my wife discovered I was idle, so instead, I decided to browse Facebook Marketplace. I occasionally have a look to see if there are any bargains on offer. Normally, any genuine bargains don’t last very long. After scrolling down a couple of pages, I found a Zoom G2.1u guitar effects unit listed as non-working for sale for $5. I was interested in this because I have attempted to teach myself the electric guitar over many years. I usually only stick at it for a few months before some project demands all my spare time. As the seller was only ten minutes away from me, I thought it might be worth risking five dollars. I messaged the seller, and he said it was still for sale as a previous potential purchaser had not turned up. So it was mine if I came straight away. He was a stereotypical young muso and could not find the effects unit buried amongst all his musical equipment (junk). He even offered to pay me five dollars for my wasted trip. I said I was willing to wait a little longer while he dug a little deeper. He eventually found it, almost in plain sight, in a desk drawer. siliconchip.com.au Australia's electronics magazine April 2025  93 From top-to-bottom: • The Zoom G2.1u guitar effects unit. • A close-up of the XC9502BO92A DC/DC controller IC. I wasn’t initially sure whether the fault was due to this controller IC or the transistor in the photo below. • I used a TO-126 package BD140 transistor to replace the faulty SMD 2SB1706. 94 Silicon Chip The Zoom G2.1u was released in 2009 and has many inbuilt sound effects, called patches, some of which replicate the sounds produced by various guitar amplifiers. It could be powered by either four AA cells, a 9V plug pack or via the USB port. When I got home, I opened up the battery compartment and noticed that a couple of the battery terminals were very rusty. I immediately got my hopes up, thinking maybe the only fault was the rusty terminals that needed cleaning. No such luck. After cleaning, the unit was still dead. I removed the separate battery compartment and found the positive wire had corroded away from the rusty battery terminal. I still had my hopes up for an easy fix. I cut a piece of brass shim to cover the rusty battery terminal, soldered the positive wire to it and refitted the batteries to the case. This time, the effects unit showed some sign of life; that is, a single LED lit. Not having much of an idea of how the unit worked, I pressed various buttons and twisted knobs with no change in the display. It was time to download the 21-page user manual to learn how to operate the unit. Using information from the manual, I performed a factory reset, which briefly brought alive more of the LED digital display before it reverted back to the single LED. It was time to do a Google search for some repair ideas. There was a vague mention that a single LED lit indicated a flat battery, although the manual indicated that “bt” would be displayed. I tried powering the unit from both the plugpack and the USB port with the same result. After a break, I ran another Google search and eventually found a service manual. Still sticking to the power supply investigation, I found that the various input power sources are regulated down to 3.3V by a simple surface-mount three-terminal regulator. This checked out to be working satisfactorily. Further studying of the almost unreadable service manual circuit diagrams showed there was another more complex dual power supply. This indicated that there should be 1.26V somewhere on the main board loaded with surface mount components. The 1.26V looked to be produced by a surface-mount XC9502BO92A two-channel step up/down DC/DC controller IC driving a 2SB1706 PNP surface-mount transistor. There was no 1.26V output. At last I had something to work with! Either the controller IC or the PNP transistor could be at fault. I checked for sources of these components. The controller IC is listed as obsolete but could be obtained secondhand from the USA for $4.30 plus $44 postage. There was no way I was going to pay that on the chance it was the regulator that was faulty. The transistor was available as a bundle of five from interstate. I did subsequently find some more affordable quotes for the controller IC from China. However, the controller IC seemed to be providing a drive voltage to the transistor. Before outlaying any money, I decided that the best option would be to locate and try a substitute transistor for the 2SB1706. It was not too demanding in its specifications, being listed as a low-frequency amplifier with a collector current of 2A. I had a TO-126 package BD140 PNP transistor in my spare parts. Although not an SMD, I thought it would be a close enough electrical replacement for testing purposes. Australia's electronics magazine siliconchip.com.au Silicon Chip PDFs on USB EACH BLOCK OF ISSUES COSTS $100 NOVEMBER 1987 – DECEMBER 1994 JANUARY 1995 – DECEMBER 1999 JANUARY 2000 – DECEMBER 2004 JANUARY 2005 – DECEMBER 2009 JANUARY 2010 – DECEMBER 2014 JANUARY 2015 – DECEMBER 2019 OUR NEWEST BLOCK COSTS $150 JANUARY 2020 – DECEMBER 2024 OR PAY $650 FOR THEM ALL (+ POST) WWW.SILICONCHIP.COM. AU/SHOP/DIGITAL_PDFS I unplugged all the jumper leads, removed the main circuit board from the case and located where the controller IC and transistor were positioned. I carefully gripped the 2SB1706 surface-mount transistor with my finest needle point pliers and de-soldered it. I knew the transistor was de-soldered when the pliers clicked together and the transistor disappeared into a corner of the room. Oh well, I was committed to changing the transistor, faulty or not. I used fine tinned wire to join the surface-­ mount pads to the relatively fat legs of the BD140 and used double-sided tape to hold the BD140 down. I just powered this board up by itself and was pleased to see 1.26V appear at the correct location. I reassembled and switched on the effects unit and saw the led display go through it self-check routine on startup. Now to test it properly. I dug out my guitar and plugged it in to the input, and the headphones into the dual headphone/amplifier output socket. On playing a note, I was greeted by the most horrible (to my ears) distorted sound coming from the headphones. I thought I would now have an audio problem to fix. This unit comes with a host of inbuilt sound effects that you can create yourself. A couple of pushbuttons select the various patches. I tried selecting a couple of patches and found different levels of distortion. I finally stumbled on some clean guitar sound patches. I had apparently started testing with patches that were deliberately distorted guitar effects. I grew up in my teenage years during the 1960s listening siliconchip.com.au to instrumental bands such as The Shadows. My guitar listening tastes have not matured much since those days. The later effects pedals that duplicate sounds from those days are reverb and delay, which mainly embellish the original guitar sound and don’t distort it so much. Anyway, I have a lot of learning to do to realise the potential of this effects unit bought at a bargain price and repaired at zero cost. If I decide later to sell the unit, I will replace the BD140 transistor with the correct surface-mount transistor to maintain its originality. B. B., Arana Hills, Qld. 2009 Honda Jazz fan controller repair My daughter rang and asked if I could have a look at her Honda Jazz, as the heater/air conditioner blower was only working at maximum speed. I have seen this sort of fault before. The fan speed is usually reduced by series resistors, mounted so the air from the fan flows over them to keep them cool. Newer cars use more efficient pulse-width modulation (PWM) to control the fan speed. I googled the problem before she arrived and found that there is a module that’s held into the fan shroud by two screws. It was deep inside the passenger foot well and difficult to get to. The first step was to empty the glove box and release the two arms that support the lid in the open position. That allowed the glove box lid folded down all the way, so a long-shaft Phillips screwdriver could be used to remove the top screw that holds the resistor module in place. The next step was to remove the under-dash shroud and lie on the floor to access the bottom screw using a very short Phillips head screwdriver. This was achieved after some uncomfortable contortions. The module came out easily and I unplugged the wiring connector. It has a perforated metal cage covering the resistors. I was able to bend back some tabs to remove the cover. The resistors are a series of wire coils of differing size and gauge. I could see the fault straight away. There is a springy metal arm that is soldered to a metal tab; if the module gets too hot, the solder melts and the springy metal arm loses contact, isolating the circuit. The solder had aged and cracked, letting the metal arm move away from the tab and open the circuit. The fix was to solder the arm back to the tab. I refitted the metal cover and installed the module back in the car. The fan now worked on all four speeds, so my daughter can now use the air conditioner without getting her hair blown all over the place. SC J. W., Hillarys, WA. Australia's electronics magazine This module (shown with the shroud removed) from a Honda Jazz is used to control the fan speed. The arrow shows the location of the failed solder joint. April 2025  95