2325 Bad Power Amp P700 Follow-Up

Velox

Just a bug hunt, Ripley..
I had posted a prior thread http://audiokarma.org/forums/index.php?threads/2325-pegged-signal-strength-meter.788198/ about working on a dead 2325, woke up on DBT after removing both power amp assemblies, had a pegged signal strength meter on FM only, with great help here got that fixed after replacing bad transistor on the MPX board. Still working on trying to bring this receiver back and have one good power amp board, one bad. Recapped them both and wanted to provide a follow-up here. Checking components on the bad amp board found multiple bad transistors, burnt resistors, shorted outputs etc. Replaced them all and finally got protection relay to click on. Unable to zero the DC offset or obtain proper idle-current adjustment. Replaced H701-702 differential pair on advice found in prior threads this forum and now able to zero the DC offset! Never could get idle-current above 2mV R240 fully clockwise, little response to adjusting R240 although could get near zero turning full counterclockwise. Finally decided to pull R240 see photo below. OUCH. Awaiting parts to try again! Thanks again to Forum for all the info and help.
Bad Pot.jpg
 
Great work. I hope the new pot fixes your problem. A 2325 is my daily driver. It has exactly the sound I like for my classic rock and it has the power to drive just about any speakers. Bringing one of these back to life is a worthwhile endeavor.
 
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