Hi all
I was asked by a friend to look at this.
Was sold tested working on ebay. Returned faulty
Bypass OK no effects
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I found bc309 gone replaced it
Now I have signal passing through. But no effects.
I have replaced lm339 4013 for new.
I have 13v supply.
Putting a signal gen on it I can see signal at pin 2 of ic2. And I can see signal at pin 12 of ic2
Checked over the board for burnt stuff etc
Checked resistors OK. I'm beginning to suspect sad1024.
This has come to the limit to my skills. Any help please

Schematic to follow

Thanks