[Jack[_11_]]

Dave Platt wrote:
In article , Jack wrote:

Given the behavior described above I can only guess that a rise in
voltage in the main amp produced by turning up the volume with the
speakers turned off somehow corrects the condition causing this problem,
but at the moment I don't know what this condition might be.

One thing to suspect in cases like this, is a bad electrolytic
coupling capacitor between one stage and the next.

Bad output-protection relays can also cause this sort of "turn it up
far enough and it starts working" problem.

Usual next step is to use a signal tracer / oscilloscope, and see how
far through the output circuitry you can detect audio when it's in the
"not working" condition.

Hi, Dave, thanks for the suggestions... I just opened up the unit and
have it sitting here in front of me and I was just about ready to do as
you suggest, see how far through the circuit the signal goes, except
that I don't have a signal generator. I plan to just turn the unit
ontune in to an FM station and probe for voltages. On the schematics I
see where the output from the power transistors goes through the relay
before going to the speakers. I plan to probe both sides of the relay to
see what I get. I will post the results.