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HarmAn Kardon 930 Bias Adjustment Help

The adjustment pots do look to be of decent quality, however, they do appear to be "open" vs sealed. If you have doxitt, you could try and spray some on the wiper of it and turn it back and forth a bit, then back to where you have it set. This MAY help you determine if it's just the trimmer or some other issue exists. Best solution is to replace both with modern sealed Bourne's or similar trimmers.
 
Running into a similar issue with the hk930. Pre driver has been recapped, new bourns trimmers. All transistors (except the 4 outputs) replaced. L channel biases fine to 15 mv. R channel goes only to 3mv max, further adjustment of trimmer reduces the bias again.. Im yet to check and make sure the transistors are all inserted correctly, the no marking boards are a PITA when working...

Edit - Solved
Wire to one of the outputs emitter was broken. Resoldered and all is well!!
 
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