modified 6 years ago

How to repair noisy crackling trimpot

00:20:39

?? Yesterday the left channel on a receiver started popping and distorting. Then it dropped out completely. I noticed the bias on the power transistors was gone. I wiggled the trimpot (open type) and the bias and the sound came back, but then it started popping again. I tried WD-40, alcohol, graphite from a pencil... While it  improved, it still refuses to make good contact and crackling is still there. Any ideas?

published 6 years ago

Robert_Kidd

6 years ago

You’ve tried all the obvious quick fixes. Is a replacement not practical?

giomix

6 years ago

Maybe a not good contact between graphite and metal pin ?

westelaudio

6 years ago

@giomix when I put a screwdriver on the wiper contact touching the graphite and hold very still it seems fine. So it seems that the wiper is the issue.

westelaudio

6 years ago

@Robert I think I'll order a new 10k trimmer tomorrow, might be a bit of a bo

westelaudio

6 years ago

bodge to get it in tho, since I'm pretty sure the pin spacing will be different.

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