[Major Debacle]

Dave wrote:
"Readily Visible" wrote in message
...
I understand. But doesn't the fact that the left channel continues to be
the one that drops out when I switch the right channel preamp output to
the left channel main amp input and same for the other two ins and outs
at the back of the unit... doesn't this isolate the problem to the main
amp section? The left channel is out at the moment and operating the
tape monitor switches does nothing to bring it back. But turning up the
volume to just past halfway *always* brings it back.


You are absolutely correct, I did not read your post clearly enough. If the
problem stays with the amp when the channels are switched, it's definitely
in the amp. Usually when transistors start to fail you get static, not the
fading in/out you describe. I'll keep my fingers crossed for you that
cleaning the relay works... it can be a real pain to track down this type of
fault. I have spent literally days working on a piece of equipment and it
ends up being something I never even thought of.

It's been 6 hours now and the left channel appears to be fine. I think
that was it! Your story of finding the solution in a place you never
thought of looking reminds me of when my truck wouldn't start last week.
The first thing I checked was the spark on my after market MSD Blaster
ignition unit and I had spark all the way to the end of the plug wires
so I figured it *had* to be the fuel. I spent two days tearing apart the
carburetor four different times. In desperation I tried changing the MSD
ignition back to the stock unit which was still in the truck and BAM! it
started right up. I changed back to the MSD ignition and it had spark
but no start. Changed back to the stock ignition and BAM! it started
right up again. I chucked the MSD ignition.

After all that aggravation with futilely tearing apart the carb in
frustration, I guess I was due for an easy layup with the Pioneer. I
guess I was tricked by the fading out and fading in into thinking it
couldn't be the speaker relay. I have never been so happy to be wrong!