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<\/a>Electrolytic capacitors<\/p><\/div>However, with a little\u00a0knowledge of practical electronics, DIY\u00a0repair\u00a0is possible and\u00a0can be incredibly cheap — especially if it involves a power supply and faulty capacitors.<\/p>\n
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Most modern electronic devices use switch mode power supplies, which are cheap, compact and very efficient. They work by rapidly switching the power off and on to convert high voltage to the required lower voltage(s). Capacitors are just one of many critical components for\u00a0switch mode power supply operation;\u00a0they\u00a0store small amounts of\u00a0electric charge and smooth out voltage changes. Some capacitor types are prone to failure, causing low voltage output and\u00a0a device that doesn’t work as expected.<\/p>\n
Over the past year or so, I’ve repaired\u00a0three different\u00a0devices that were otherwise destined for the\u00a0recycling depot.\u00a0In each case, faulty\u00a0capacitors were the cause of the problem.<\/p>\n
Cold, dead laminator<\/h2>\n
An A3 laminating machine was in the\u00a0recycle pile at work. What’s the point of having it repaired\u00a0when a replacement unit is only\u00a0$25? I gave it a quick look-over\u00a0and it didn’t seem to be a mechanical problem (for example,\u00a0a broken gear), so I took\u00a0it home and took\u00a0the cover off.<\/p>\n
Visual inspection revealed\u00a0that one of the capacitors on the power supply was bulging. A domed or bulging top is a dead give away for a failed capacitor. Once I desoldered the suspect cap,\u00a0I could see that it had definitely failed. I installed\u00a0a replacement of the same value, which I already had on hand. I also replaced the capacitor next to it\u00a0since I was in there anyway. Et voila! The laminator was alive once more!<\/p>\n
<\/a> <\/div> <\/div> <\/a> <\/div> <\/a> <\/div> <\/div> <\/div> <\/a> <\/div> <\/div> <\/div> <\/div>\nGrounded\u00a0AirPort<\/h2>\n
A few months back,\u00a0I purchased\u00a0a defective Apple AirPort Express on\u00a0eBay. It was listed as not working, but if I got it cheap\u00a0it wouldn’t matter if I couldn’t get it going. I paid just $18, delivered.\u00a0I think they were around $90 when new, and the current model\u00a0would set you back around $150.<\/p>\n
For this one, I went to Google for some info on the symptoms\u00a0and solutions. As always, there’s an endless supply of others sharing their experiences and thanks to ‘thedivvie<\/a>‘ on YouTube, I knew exactly what I needed to look for. The power supply has\u00a0two capacitors that are prone to failure, causing symptoms the same as\u00a0my dead AirPort.<\/p>\n Apple obviously made AirPorts to be totally disposable; they’re not at all repair-friendly. The only way to get inside one\u00a0is to cut it apart with a hacksaw. Carefully. I located the suspect caps, as shown in thedivvie’s video, and replaced them with a couple I had on hand. After reassembling with cloth\u00a0tape (the easiest\u00a0way to hold it together after sawing it open), I had a fully functioning AirPort Express again. Now I can wirelessly stream music to\u00a0my garage from anywhere on my home network. \ud83d\ude42<\/p>\n Just last month,\u00a0a friend replaced his\u00a0defective\u00a0Digital Video Recorder (DVR). Its symptoms weren’t immediately obvious as a power supply issue, but I asked if he\u00a0would pass the unit on to me instead of tossing it out. He did. Thanks, Fez.<\/p>\n The\u00a0prime suspect was clear\u00a0as soon as I opened the unit — a capacitor with a rounded top. I tested the power supply’s output and\u00a0confirmed that even without a load, the 3.3 and 7 volt lines were\u00a0low. Definitely worth making a\u00a0quick trip to Jaycar<\/a> to get the right value replacement capacitor. With that installed, the unit powered up properly and is now fully operational.<\/p>\n A replacement DVR would set you back around $300-$500. A\u00a0professional might\u00a0charge $100-150 for this repair, but\u00a0you’d probably still opt to replace the dead unit, since you’d get\u00a0a newer generation of technology complete with warranty. Now, this old DVR will live on for another few years.<\/p>\n In summary, it took a few hours of my time and roughly 95 cents for each capacitor to keep these three items in service. Admittedly, I was\u00a0lucky, as\u00a0the repairs were so simple. I don’t have the skills or enough knowledge to truly troubleshoot power supplies, but\u00a0sometimes you can get away with\u00a0knowing just enough. \ud83d\ude42<\/p>\n Obligatory disclaimer: This is a summary\u00a0post about my experience repairing a few devices. It should not be used as instructional material, nor as advice to undertake this type of repair yourself. Dangerous voltages are present and exposed when these devices are disassembled.\u00a0Do not attempt any disassembly of mains-powered devices unless you have the necessary knowledge to do so safely and without electrocuting yourself!<\/p>\n Just last\u00a0week, my neighbour mentioned her\u00a0TV remote wasn’t working. I coaxed open the case and using\u00a0my multimeter I found\u00a0a cracked solder joint on a battery terminal. Not a capacitor problem, but still an easy repair. An minute with the soldering iron and this too lives another day!<\/p>\n <\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" It costs a lot to get faulty electronic devices repaired, right? High labour costs\u00a0and\u00a0cheap retail prices mean\u00a0a low threshold when deciding whether to repair or replace. However, with a little\u00a0knowledge of practical electronics, DIY\u00a0repair\u00a0is possible and\u00a0can be incredibly cheap — … Continue reading <mini_rant>\u00a0<\/code>Is this really<\/em>\u00a0necessary,\u00a0Apple? How about designing repairability into your products, you know, as a small gesture to our planet and to your customers? A little less waste helps and I really don’t think your bottom line would suffer noticeably.<\/mini_rant><\/code><\/p>\n <\/a> <\/div> <\/div> <\/a> <\/div> <\/a> <\/div> <\/div> <\/div> <\/a> <\/div> <\/div> <\/a> <\/div> <\/div> <\/a> <\/div> <\/div> <\/div> <\/div>\nDefective DVR<\/h2>\n
<\/a> <\/div> <\/div> <\/a> <\/div> <\/a> <\/div> <\/div> <\/div> <\/a> <\/div> <\/div> <\/div> <\/div>\nAnd so…<\/h2>\n
PS<\/h2>\n
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