Hi all,
thanks for the awesome videos and a great forum for a start! Still new here but already a fan
So Google turned up the post about the yamaha amp fix, and I seem to have a problem with my trusty rx v661 also. Unfortunately not C405 I don't think - it turns on fine, but goes into protection mode due to low voltage on one of the monitoring circuits. I traced it down to a +12V line, which shows +4V. Great I thought, replace that and I'm sweet - but no cigar. Turns out the old regulator still regulates out of cicuit, and after the replacement I'm still at 4V.
Then tried to isolate on which board this is happening, and turns out when I disconnect the dsp board - taddaaa - back to +12.
So I'm a reasonably good hobbyist, certainly no professional... hence my question, what can cause a voltage drop like that? Looks like an almost-short somewhere I would have thought, right? I assume burnt caps can do this, they all look pretty good though. Nothing obviously went up in a puff of smoke. Any other suggestions on what to look for?
My other question, I have measured all the voltages through from the supply onwards, according to the service manual, and for a number of them (mostly AC but a few DC ones as well!) they are a fair bit higher than in the manual. Can't remember any exact numbers at this point, but what sort of tolerance would you expect? Is higher ok? They're not hideously over the top, but maybe 10% at times.
Would really appreciate pointers in the right direction, thanks heaps!
Andy
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