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Volume Decreases and Increases on it's own-the 39-6C
#1

I completely restored this radio inside and out--and it's a beautiful little set that plays quite well. I had to replace it's output transformer and rewire the main transformer. It was quite dirty when received. The problem is when it's playing, the volume decreases down to about half the db.-then back up on it's own- all within several seconds. When it warms up, it (usually) doesn't do that any more. Any suggestions? Thanks!!!!!
https://picasaweb.google.com/lh/photo/nL...directlink
#2

My first thought is a tube filament (heater) that is intermittently opening up. Turn the radio around so you can see the back and watch the tubes. Wait until the set has cooled off for awhile, then turn the set on and watch the tubes (in dim light so you can see the glow of the heaters). When the volume drops, see if one of the heaters has gone out or appears to slowly go out, then come back as the volume begins to increase again.

If all five remain lit steadily, then your problem is elsewhere and signal tracing should reveal the faulty stage.

--
Ron Ramirez
Ferdinand IN




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