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Palm m105 Capicitor Problem

PalmPilot image

I've owned a Palm m105 for about 18months or so now, and recently its started requiring hardware resets every time the batteries need changing. This means loss of data and full reinstall and synch of all s/w on the PDA. It turns out this is because of a Capacitor fault.

PalmPilot imageThere are regular usenet posts to comp.sys.palmtops.pilot and websites like this one where the problem is discussed and the upshot of it all is that the soldering of the capacitor that is supposed to hold a charge during battery replacement has caused accelerated aging of the capacitor and it basically won't hold the charge at a high enough voltage.

I took my 105  to our electronics wizz dude Rob today and he removed the case checked the voltage across the cap and sure enough it was only holding about 0.6v. The batteries are a pair of 1.5v AAAs (arranged in series) so obviously it requires more than 0.6v to keep operating. Rob removed the old cap (location shown by a read circle on the PCB image on this page) and now I'm looking for a replacement.

The only thing that looked anything near suitable at RS-Components (our NZ equivalent of RadioShack) was a cap that was 10mm in diameter. This will be too large for sure.

While I had the top off I thought I'd have a look at some of the components. The processor is a 16MHz Motorolla DragonBall-EZ mounted upper-centre on the PCB