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SERVICEMAN’S LOG Remotely Interesting Dave Thompson The internet is a blessing and a curse. It lets us do lots of things from just about anywhere, but it can also give access to people we don’t want accessing our files and bank accounts! This has made some people nervous about remote access, and that makes my job more difficult. This modern age is something else; I’ve said and thought it, as have many others. However, engineers and philosophers have been saying so since the dawn of time. At one point, a sundial was the pinnacle of technology. They still exist, albeit mostly as garden ornaments, but I have seen some very old, used and working examples in Rome and other historic places. Modernisation is always a double-edged sword. What makes better microwave ovens also makes more effective weapons. Since we first had the technology, remotely controlling something has been a prized goal. Early radio-controlled model aeroplanes were basic and usually only had just one channel controlling a rudder via an escapement-type arrangement. The transmitters were large, valve-based, battery-­ powered, and usually just a switch to change between left, right and oh-it’s-crashing modes. The range was not great back then. These days, the transmitters and receivers are much more advanced and reliable, with multiple channels, continuous controls and such. Some even provide remote point-of-view (POV) video from the aircraft! When I was a kid, back in the chalkboard days, my parents had a remote control for their TV. It was my siblings and me. Fortunately, we only had two channels, so a trained chimp could have done it. It wasn’t long before Dad modified our TV to use a wired remote: a metal box with a 84 Silicon Chip pushbutton that had a wire running around the skirting board into the back of the TV. I, for one, was very relieved by this innovation. Pretty soon, those old clunky ultrasonic controllers came along. I still see them occasionally on old American TV shows, making an exaggerated click sound and hand movement when operated. Even when the newfangled infrared (IR) LED types replaced them, the remotes on those shows still made the click sound! In the 1980s, suddenly everything was remote controlled. Stereos, radios, heaters, ovens; anything that would help sell appliances. It got so bad that people had special pockets in their chairs for all the remotes. Then the universal remote came along, and that changed everything (pun intended!). Of course, most of us still have multiple remotes these days for all our devices, but the whole remote philosophy really expanded and came into its own during the recent pandemic. Many companies found that their employees could work from home and the job would still be done (something some of us have been doing for so long that we’ve forgotten what the others look like!). In fact, many found that the better work/life balance actually improved productivity and boosted output, even though fewer actual hours were being worked. Spending time working that would otherwise be wasted commuting helps a lot, too! This caused a lot of wringing of hands and gnashing of teeth amongst bosses and ‘human resources’ departments, who considered that despite the increased productivity, they were somehow being cheated out of chargeable labour by allowing people to work from home. Some companies have embraced the new ethos, and why not? Some have a policy that workers can choose to come to the office or work from home, or use a ‘hybrid’ model that involves doing both on different days. Some ask that workers come in at least a few times per week/month to stay in touch with their teams. The reality is that with technology the way it is now, people can use the likes of Zoom, Teams or even a basic remote desktop app to do their jobs effectively. In some cases, the company can even close or downsize expensive and capital-draining offices in Australia's electronics magazine siliconchip.com.au Items Covered This Month • The perils of remote access • Repairing a car’s ignition unit • A dim clock backlight • Sony ICF7600D receiver repair 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 favour of working from home, with appropriate expenses and compensation. Of course, we computer nerds have been able to operate computer systems remotely since the 1990s. One could argue that hackers have also been able to, because if you open the door to someone, a sneak thief may take the opportunity. A huge industry was then built around network and server security. As is becoming all too clear, this is far from foolproof; we are always hearing about breaches in defences, especially now we have state-sponsored players in the mix. Software like Norton’s PC Anywhere and eventually Microsoft’s Remote Desktop (which is built into all versions of the operating system for client use, but only Pro versions for controlling use) became the gold standard of remote access software. Now, anyone with an internet connection and the correct access permissions could ‘remote in’ and control the host computer as if they were sitting in front of it. As soon as these apps were released, the bad guys started looking for ways through them. Local firewalls became extremely important, and everyone had to learn a new set of new words if they were going to use these utilities. Windows started shipping with a built-in firewall; routers and modems had their own hardware firewalls, and techs suddenly had migraines from all the hoops they had to jump through to allow authorised remote connections to happen. Nowadays, it is relatively straightforward with utilities like TeamViewer and virtual private networks (VPNs), which offer a certain amount of built-in security, depending on how they are set up. The problem is that most ‘hackers’ and scammers now realise that trying to get through is very difficult compared to the old days, so they play to the obvious weak links in all these systems: the user. And they are very good at it. The way to gain access to siliconchip.com.au someone’s system is to get the user to install a remote viewing app and give the scammers access. Of course, the ways they do that are as varied as the scammers. I have known several people who have lost considerable sums of money to these con artists. In one, a 70-year-old widow was played for over a year to the tune of $85,000 in a so-called ‘lonely hearts’ con by some very glib, professional shyster. I warned her it was a scam (she called and asked me about it and I told her to bail). Her bank put a hold on payments going overseas, but she overrode them or went to a money transfer place and sent it that way. While technology is robust enough nowadays that I haven’t seen an actual virus infecting a computer in over 10 years, users are unfortunately falling for these scams more and more. During the pandemic, I was still getting a few support calls, and I would ask them to download and install the run-and-stand-alone version of TeamViewer to be able to see what was going on with their machines. TeamViewer is a popular remote control program for Windows machines. I used that because it doesn’t require any fiddling with network settings, nor even installation. You just run the downloaded file and choose ‘run once’. When it fires up, they then send me the randomised computer ID number and password displayed in the app, and I can then connect Australia's electronics magazine November 2025  85 and log in right away from my machine. Once there, I can do whatever I need as if I’m sitting in front of it. I repair any problems; transfer any files I might need to run locally there; and do whatever. But many users are so paranoid now (and rightly so!) that as soon as I suggest I can do that, they get nervous and hem and haw. Many would ask if I could come out to their place and do it, but under the lockdowns, that just wasn’t possible. Not to mention that I didn’t want to put myself at risk anyway – I haven’t contracted COVID-19 yet, and I have no plans to change that at this stage! For those that did agree, I did the job and often fixed their problems, but then when it came to payment, they would stall and say, well, you never really did anything, so I’m not paying. That was extremely disappointing coming from long-term clients, and of course once I log out, I can’t log back in and return it to how I found it. Without the machine physically in the workshop, I have no leverage regarding payment, and instead rely on the goodwill of people to actually pay for the job I’d done. Of course, I altered my prices where required, but overall, it left a sour taste. That was pandemic times. Lately I’ve had a few overseas clients from Australia, the USA and England, and the same model still stands. I can use remote control to gain access to the computer and help the customer. But of course, this 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. 86 Silicon Chip is only for software-related problems where Windows is still running. If it isn’t, then we have a problem. So how to resolve problems like Windows won’t start, the network adaptor is not found, or it is faulting and I can’t access the computer remotely? I had to change strategies and see if I could inspire the owners to do the job for me. Now, obviously, some are not going to be up to that, but for those who might be able to help, I’d give them the option and use a well-known phone video call app to see what we could do together. This method is far more difficult. While most people have a smartphone these days, not everyone has this app installed. So that’s the first hurdle. Once they download and install it, we then do a test call. It works pretty well, even on slower connections. The video quality is good enough; with communications sorted, we can get down to basics. It could be as simple as rebooting the machine – many people don’t know that holding the power button down resets it. If that doesn’t work, we can look at the BIOS, Windows startup menus and trapping stop codes/blue screens that often flash so quickly on modern machines nobody is even aware they are there. That can tell me a lot. How this process goes tells me a lot about the person at the other end, and whether I have to suggest getting someone else in physically. Recently, I was chatting with a client who had relocated to northern Spain and was having trouble with their laptop. It was too hot to touch and had slowed right down, so of course my immediate question was: are they using it on their lap or a duvet or similar that could be blocking the air intakes on the bottom? I was told that it was sitting on a timber table and running from the mains power supply. There are only two reasons it could be that hot: the CPU fan isn’t running, or the airways are blocked inside. Either way, it was going to have to come apart. This was not going to be a problem, as I knew this person was handy with a screwdriver and could pull it apart. The problem was that they hadn’t attempted a challenge like this on a new, aluminium-­bodied, slimline device. Half of my task here was going to be giving them the confidence to do the job. I found a strip-down video on YouTube for this model and sent them step-by-step instructions on where the screws were, including a couple hidden under bumper feet. The biggest challenge was for them to crack the clips holding it together. As is typical of me, I have a dozen different spudgers to do this with. He used his fingernails at my suggestion and eventually cracked the back off. He’ll need a manicure, but otherwise, all was well. As I thought, the fan was choked, as I could see as he played the phone camera over the innards. He had no compressor, so it was a vacuum cleaner to the rescue. It sucks (har!), but needs must. I advised him to keep holding onto the nozzle at the end to ground it as much as possible, and avoid getting near the motherboard itself, a challenge given the tight confines of a laptop. Still, he managed to get rid of most of the dust and lint that always builds up in those ducts and heatsink vents. Once done, he just reassembled it and fired it up, and all was well. No fan thrashing, no heat buildup. So, a good fix. But how does one charge? I didn’t. They did all the work. I just stood by, advising via the internet. It is not easily Australia's electronics magazine siliconchip.com.au chargeable anyway, even without the logistics of the international payment systems. Another interesting fix happened recently with a friend of my wife. This friend lives in the USA and is currently enduring a bathroom renovation and all that entails. If you’ve ever done any renovation work, you know it takes three times as long and costs twice as much as we budget for, not to mention the mess. I heard they had allowed one week for the reno; I thought that was a very optimistic timeframe. From personal experience, just clearing the old stuff off the wall, the tub, loo and shower out was going to take longer than that, even if all you used was a sledgehammer! Anyway, while the subbies were moving around, they somehow damaged an electric ‘Roman’ style blind. Usually, these come with a cord of some kind with which to raise and lower it. Like an old blind that people of a certain age will remember, you pull it down by the bottom and is held in place until you give it a little more, then it rolls up again. These blinds have no springs to wear out; the cord winds them up and down. Anyway, this was a custom-made blind that spanned a set of doors, so it was quite large, and it was controlled by a motor at one end. This was powered by batteries and a controller that replaced the cord. Somehow, someone had cut through it, leaving the controller/ battery holder on the floor. Tradies! So, another WhatsApp call then. I could see the problem; it was obvious, really. But this should be a simple fix. The difficulty was that this woman didn’t even know how to hold a screwdriver. The male of the house was no help either, so it was down to me to guide her in fixing the problem. I told her she would need an inline connector and found and sent a link to one that should do the job. I also included a link to a small pack of heatshrink tubing. It could all be delivered within 24 hours (which is still amazing to us here), so we prepped the rest in the meantime. Luckily, the wires were coded as to positive and negative, as many cables are, with a black stripe down one side. I got her to strip the wires; without a stripper, or even a Stanley knife, we had to improvise. A sharp paring knife was used, and she was very careful (almost too careful) not to hit the wiring inside the insulation. But she got the plastic clear and twisted the ends. The other bits arrived the next day, and she cut the heatshrink tubing to size and slipped a big piece over the whole lot, then she used the twin inline connector to reconnect that battery pack. She’d found a small jeweller’s-type screwdriver and managed to connect everything up. She tested the control, and the blind operated as expected. I got her to put the heatshrink over the whole connector, and she used a BBQ lighter to carefully shrink it down. She was chuffed, and it was a good fix. Job remotely done! Transistor-assisted ignition unit repair In the last years of high school, an adult friend bought me a copy of Electronics Australia. This got me interested in electronics, and I continued to buy EA magazines while at school and after leaving. I built several of the projects, sometimes buying kits and sometimes sourcing the parts myself. A few years after finishing school in 1970, I got my first siliconchip.com.au Australia's electronics magazine November 2025  87 car, a 1962 EK Holden station wagon. I had to rebuild it as it was missing many parts, including the engine and the entire front end. Through the late 1970s, 1980s and early 1990s, I had several 1960s Holdens. In the December 1979 issue of EA, there was a transistor-­ assisted ignition unit featured. After reading the article, I decided to build one for my car, which had the standard Kettering ignition system with points, condenser and coil. The article promised better performance and better fuel economy. I don’t remember if I sourced the parts or bought a kit from one of the multitude of kit suppliers back in the day; possibly the latter. After installing the unit, I notice an improvement in performance, with the engine running smoothly and increased torque at lower engine RPM. The car went well for quite some time, but then suddenly stopped for no apparent reason. I did some troubleshooting and determined that the transistor-assisted ignition unit had failed, which was a big disappointment, as it had been going well up until then. A quick rewire back to the standard Kettering ignition and I was on my way again. I had installed the transistor assisted unit in such a way that in case of a failure, I could easily swap back to the original ignition system. Later, at home, I took the unit out of the car and inspected it. I could see straight away that the three 2.7W 1W resistors had overheated and burnt part of the circuit board, destroying the tracks and causing an open circuit. I decided that the three parallel 2.7W 1W resistors were under-rated for the application, so I replaced them with two 1.8W 5W resistors that I had on hand, spacing the resistors off the board. Because the PCB tracks no longer existed, I used the leads from the resistors to make new “tracks”. I reinstalled the unit and I had no more problems with it after that. I still have it, but our current cars have either fuel injection or electronic ignition with a carburettor, which has made this unit, which was excellent for its time, redundant. Bruce Pierson, Dundathu, Qld. Sony ICF7600D receiver repair I had a Sony ICF7600D radio receiver for many years, which I purchased on Norfolk Island when travelling with the RAAF in the 1970s. It was a beautiful radio, made in Japan, with synthesised tuning, an LCD readout and a separately powered clock. The bands it covered were LW, MW, SW to 30MHz, plus the extended VHF FM band, and it had SSB demodulation support. It had two dedicated AA cells for the clock and four for the radio, which could also be powered from a mains power supply. I relied on this radio as a secondary alarm clock during my time as a regional airline pilot, as I could never be late; therefore, I relied on the separate cells. After leaving the industry, I used the radio less, and it languished in a drawer. I forgot to remove the cells, and they inevitably leaked, so I cleaned the compartments and contacts and all was well. Many years later, I decided to get rid of things that I had 88 Silicon Chip Australia's electronics magazine siliconchip.com.au ← The circuit for a transistor ignition unit from the December 1979 issue of Electronics Australia, which Bruce built to put into a 1962 Holden station wagon. A simple self-oscillating white LED driver to replace a fluorescent lamp. When Q1 switches on, it shorts out the bottom end of L2. When it switches off, the voltage at that point flies up above the 1.5V supply to power the two white LEDs. not used in a while, including the radio. I plugged it in to test it, but nothing happened; it was completely dead. Trying fresh cells instead of the AC adaptor did nothing. On opening the case, evidence of the previous leaking cells was visible near the compartment and the connecting wires appeared corroded, so I cleaned everything and replaced the wires. The radio still refused to work. I was able to download a schematic diagram, but my board looked slightly different. I started tracing the 6V from the cells and it was apparent on one side of a wire with a ferrite bead, but not on the other. Assuming a dry joint, I resoldered the wire. As I did, I noticed that the wire moved within the bead. Using tweezers, I pulled half of the wire out and, on close inspection, it was corroded inside the bead, likely due to the aforementioned cell leakage. A new piece of copper wire simply brought the radio to life. Rowan Wigmore, Hadspen, Tas. I soldered the toroid winding and a 2N5551 NPN transistor with a 1kW base resistor onto a small piece of matrix board, and connected two white LEDs in series between the collector and emitter of the transistor. The clock has two small perimeter slots on its face at the 11 o’clock and five o’clock positions that are relatively transparent. I hot glued LEDs at these positions with the lens pointing inwards. When the backlight switch was operated, the LEDs lit up, and the hands could be easily seen. While the backlight is no longer spread evenly over the whole of the clock face, the LEDs provide sufficient illumination to easily check the time during darkness. SC Phillip Webb, Hope Valley, SA. Seiko Bedside Clock backlight repair In the early 1990s, I received a Seiko bedside alarm clock in recognition of 20 years’ service with my then employer. This clock has performed perfectly in timekeeping, but its fluorescent backlight gradually dimmed over time, then stopped functioning altogether. I finally got around to opening the case, and discovered that at some point in time, the 1.5V dry cell battery had leaked all over the small circuit board that drives the fluorescent backlight. I cleaned up the board as best I could, but could not coax the backlight into life. I immediately thought of replacing the backlight with white LEDs, but realised they needed about 3V to get them to light. Years ago, I had played around with the “Joule Thief” circuit that was easily able to light LEDs from a 1.5V cell. Looking through my boxes of parts, I found a compact fluorescent lamp (CFL) driver board with a small toroid that would be perfect for making a Joule Thief transformer. I stripped the old winding out and wound 12 turns bifilar. siliconchip.com.au Australia's electronics magazine November 2025  89