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WHAT'S UP
<20:23 EEST>
Another week, another succesful power supply fix :D This time it was the
fancy passive-cooled setup of Hoo that gave
up last December. Confused in my
eat-sleep-work/obey-conform-consume treadmill, I had done a particularly
poor job of analyzing the problem, and bought a replacement for the complete
set of the 12-volt adapter and the internal PSU.
As with last week's Power Mac supply, this was an easy and obvious problem to fix, after the somewhat tedious disassembly. Following today's throwaway culture, the power brick had no screws, and I had to pry the plastic outer casing open — using a can opener in a Swiss army knife, aptly enough. I needed something intermediate between a knife and a flat screwdriver, and it was a perfect fit :)
Inside, one electrolytic capacitor had bulged up in the usual way that many hardware geeks know. I had previously replaced more than a few capacitors in a motherboard from that era. The guts of the adapter were naturally a bit crowded, but this was a rather spacious area near the 12-volt output.
In line with these unexpected fortunes, I happened to have a suitable replacement. In this case it means that the replacement was mechanically fitting. Most of the computer capacitors are small for their capacitance, since there is very little headroom in the voltage rating. However, these voltages are hard to find in common electronics stores, and you usually end up with a bulkier cap with more headroom. Here the culprit was 680 µF at 10 V; my replacement was 1000 µF at the same voltage, which I happened to have in two different form factors. The one I used was the same height but thicker, and the aforementioned spaciousness came in handy. Since it was used as a filtering capacitor in parallel with the output, a bigger capacity would be somewhat better. This is something I have done with motherboards before, and it is in fact advisable to have headroom in the capacitance as well, since it degrades over time.
A quick test with a voltmeter and a 10-ohm resistor load, and later several hours of actual use with Hoo, confirms that this was just the fix. Doing this in December would have saved me about 100 euros, but unfortunately DIY and treadmill lifestyles do not mix. On the other hand, I now have an extra passive-cooled PSU for further hacks. For example Nunu could use some silencing, with some more hacking to adapt the ATX power pins to the iMac.
Regarding a DIY life, last night I watched Zeitgeist: Addendum. The idea of a technological utopia with no money or scarcity is naturally intriguing to me, but I am somewhat pessimistic of the transition period. The problems are similar to what I have previously thought about employment and efficiency. It is an unfair situation if one part of the world works according to the utopia, and another part does not. Everyone should change at the same time, which is pretty much impossible.
The solution might involve changing some parts of everyone's lives. Open source software, the Internet, and living off the grid are great examples of this utopia in action, even when they only cover a part of our lives. In fact, you can see the basic problem in the divide between old media/software giants and the pirate/opensource crowd. But since these movements show no signs of going away soon, I actually have a little hope for the future. It will also be interesting to see the world run out of oil, because at least some of the old giants will have to step aside then.
Anyway, it must be said (and I'm probably repeating myself) that DIY hacks like the PSU fix give me an incredible sense of accomplishment. I actually have some power over the mysterious world of electronics ;) More importantly, any DIY work is probably good for the environment, in addition to your self-worth. You are saving something from going to the landfill, as well as reducing the production of such waste. Money-wise, there is probaly not much benefit either way, but imagine choosing between these options: