Skipp,
Tom's analysis brought up an excellent point. If the amp
is an original PA-77, there should be 5 megohms resistance
between B- and ground. Easy test.
Selected bits:
>If the metering system is messed up and he is trusting it to tune
>the PA, that explains why the output is low. More than likely the
>grid meter is partially reading plate current through a fault in the
>from the B- return to the chassis. When that condition exists, the
>user will "overcouple" the PA because he "thinks" the grid current
>is higher than it really is.
Regards,
Jim, N7CXI
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