John Keiser wrote in message
...
Digging a little deeper, I can see a relay on the power amp board. I
assume
this is part of the output protection circuit. If this were the issue,
would I have any sound at all? Sound is present, just extremely low. I
haven't yet checked voltages. [Not a switching mode PS - large, very
heavy
transformer circuit.]




"John Keiser" wrote in message
...
Not shorted.
I thought of that and attached different speakers and same result.
Sound comes out of both speakers, balance controls function, mute button
drops volumne as it should.
Output meter and audible output simply dropped to marginal. [Vol on max
should be overpoweringly loud, it is now a whisper.]
Both channels equally effected.
There are perhaps 6 fuses. I removed and reset just in case they were
oxidized. No joy.
Other suggestions welcomed.


"Smitty Two" wrote in message
news
In article ,
"John Keiser" wrote:

I've owned this receiver/amp for 30 years. Used infrequently but
functioned
fine. Today, while playing a CD, suddenly stopped after 5 minutes on
low
setting. Toggled to mute, loudness, no joy. Using FM input, controls
seem
to work and I can hear music when I reach very high settings.
Sometimes
crackles to very loud but only momentary. I think pre-amp is OK.
I'm thinking some sort of protective output circuit has activated but
I
have
no schematic. Before I tear in blindly, does anyone have access to a
schematic for this [I found a source on rapidshare but file no longer
there].
Thank you.

Speaker wires shorted?





The sense range monitoring the +/- rails ,or the rails themselves, have
drifted out of kilter. Load the high one a bit, then the other, to see if
it kicks life into the amp. Monitor some zener voltages, and balance up a
bit, if that fails to ellicit anything