alfista wrote: > Anecdotally, I've seen some weird issues in some consumer electronics > when I replaced electrolytic caps of questionable pedigree with the best > stuff I could get my hands on, seems like the design was tuned for the > low budget components.
Absolutely. Some voltage regulator circuits require that you use low ESR or ultra-low ESR capacitors, while some require that you DON'T. Often you need a mixture of types. Many linear regulators will oscillate if you stick an ultra-low ESR capacitor across their outputs. Who knows what Logitech used originally and if they only used one type across the board. Does anybody know the manufacturer and type of the capacitors? And did Logitech change this when they took over. My (Logitech) SB3 is still hanging on and in daily use. For half of its life it's been plugged into a remote controlled mains socket, so that it's only powered up when I'm actively using it. This should help preserve both the electrolytics and the VFD. As a side note I did have to replace the caps in the audio section a few years ago when I realised that the analogue outputs didn't work anymore. That's was a bit OCD of me really as I don't even use them, I connect it to an external DAC! The caps between the internal DAC chip and the op-amp were back-to-front but they did agree with the silk screen. The op-amp input is biased to a higher voltage than the DAC output so the positive side of the caps should face the op-amp, which they didn't in my unit. Interestingly one of the caps between the op-amp and the RCA sockets was also open circuit yet those are not the wrong way around. I replaced all 4 signal path capacitors and normal sound was restored. It doesn't fill me with confidence about the state of all the other caps on the board, but any temptation to replace those whilst it is still working is receding fast after hearing these horror stories! ------------------------------------------------------------------------ Glenn2's Profile: http://forums.slimdevices.com/member.php?userid=19286 View this thread: http://forums.slimdevices.com/showthread.php?t=117140 _______________________________________________ discuss mailing list discuss@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/discuss
