Any thoughts on what next to look at for this problem?

Did you test the amp separately on a bench setup? Was the amp working OK before the recap?

Posting some high resolution pictures of your board might be helpful.

You were on the right track comparing the properly operating channel to the channel with the issue.

Glitch

Hi,  Yes the amp was in operation prior to the recap.

I did no adjustments until after the recap so the perhaps the problem may have existed prior to the recap, or it is after, I am unsure. But it was in use.

Now when I am adjusting the trimmers it shuts the unit down but works when the trim is left out of spec.

I am Attaching the pictures

the back

I think I found the problem...  standby.

Thank-you  for all the help!!!   It was an installation of 100 and 100k trimmers that caused both problems,  the LED for the FM strength AND the no load current setting issue.

I did verify the correct trimmers were installed on the amp board TWICE,  but the R234 was hidden behind another large green component c201,  I could make out the first 3 letters but not the 4th when I initially checked, and I moved on.

Once you asked more questions about the recap work, I looked again and finally saw the k in 100k, which was wrong for R234.  It was to be 100 .  The 100k should have been on the LED feed on board 6, which was my other problem.   Once swapped everything worked perfectly!

Thanks for all the help, your questions lead me to recheck a third time!

Best regards

Chilibt

 

I'm glad to hear that you figured out the issue. I wouldn't have guessed that particular thing was your problem.

The markings on those Piher pots is difficult to read. One tip that I have is to place the components in a block of foam that is marked for the value.

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I like to test all of the new components before I install them. After they are tested, I stick them in the foam. This makes the re-cap/re-pot procedure go faster. I've also found new parts that are technically "in spec", but are so marginal that I wouldn't want to use them.

I also mark and stick the old components in the foam when I remove them. This makes it easy to test the old components to get an idea of how well they have aged.

BTW, the adjustment for the signal strength is one that you could get away with adjusting without instruments. Tune between strong and weak stations and adjust until the display gives a behavior that you like.

Glitch