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Bass circuit problems on model 38-690
flradiodoc
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#1

01-01-2011, 09:18 PM
I am restoring a 38-690 and am having a problem with the bass amplification system. The chassis has been completely gone through and plays great. Only problem is the bass control does not do anything at all when adjusted. I have chased electrons until I am blue in the face and have gone over everything numerous times to see if I can find the problem, but to no avail.
If anyone out there can help me on this one, thanks a bunch.

Mark...
Radioroslyn
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#2

01-01-2011, 10:03 PM
Hi Mark
I took a quick look at the diagram and my hair instantaneously burst into flames!!!! A poor of a rendering of the diagram on NA very hard to follow! Generally I would check the pot for shorts to the chassis break out the Signal tracer and start at the pot and nose around a bit to hear if there is any bass boost. Key suspects would an open resistor or cap. I know it's not much to go on.
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
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