7S12 problem update


Chris van Lint
 

Thanks to those who responded pointing out the fragility of R151B.  Mine was indeed faulty, so much so that I could not just glue it back together.  When I pushed it the whole thing disintegrated.  To prove a point, I just soldered another 10K pot in place of the faulty one.  Regrettably that did not fix my problem.  Since the coarse DC offset pot is OK  which I have confirmed that by testing the voltage at the centre of the coarse pot R151A going to the base of Q163 and observing that it ranges from -12V to +12V., I am hoping that somebody can come up with another suggestion(s).  I would really appreciate some input, as this is well outside my level of expertise and it would appear that other than the DC offset the unit appears to be functioning OK.

Cheers and thanks in advance,

Chris

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