Re: Wem Copicat Mk4 repair
Assume you have checked the power rails are reasonable, the 1st stage gets regulated supply via 18V Zener so that should be circa 18V and the rectified secondary should be 20 something volts or so.
Worth comparing performance between the two inputs, if no appreciable difference then the problem would seem to be around Q3 Q4 stages.
Also check the bias oscillator (2x BFY51) is reasonable amplitude and frequency
Best Regards
Chris
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