On Thu, 12 May 2022, Peter Coghlan via cctalk wrote: > Anyway, the good news is that I think I have found the source of the > problem. One of the capacitors used to filter the (DC?, pulsed DC?, > rippled DC?, biased AC?) supply to the 9V regulator is marked 330uF/25V. > It reads 6uF on the capacitance range on my multimeter. This can't be > helping the cause. It's not showing any signs of leakage but it's got > a brown sleeve and the same logo as the nasty, leaky SXF capacitors but > it is marked KME. (I said there was only one capacitor in the filter > in a previous posting. Originally I managed to spot a little 10uF/100V > capacitor but somehow failed to notice the chubbier 330uF/25V capacitor > completing a PI filter with a small choke...)
Likely just a general purpose capacitor. I only have 2 330uF/25V 85°C Nichicon SE parts listed for the H7821 (and I have a note about one PSU of this kind having a 220uF/35V part in place of one of those too). Also no 100V parts at all, but 4 10uF/35V 105°C parts, either Teapo SE or Daewoo RS. Teapo SE and Chemi-con KME series are standard general purpose parts and given the low temperature rating Nichicon SE are likely such as well. I guess especially for standard capacitors factories ordered whatever was readily available whereas with the high-ripple low-impedance/ESR parts the choice was much more limited. Maciej