philco tropic model 42-760
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Joined: Dec 2009
City: Roslyn Pa
Your grid bias is low @6v. With 250v on the plate (pin 2) the - dc voltage needs to be -17 to -21vdc on pin 4 (grid 1). With that low of a bias voltage 2 things are going to occur. Distorted audio and excessive plate current flow on the two 42 tubes. Not good for the 42 tubes.
http://www.mif.pg.gda.pl/homepages/frank...1/4/42.pdf
Wouldn't worry too much about the vc yet I'd get the set to pass a RF or IF signal. Do you have a signal generator?
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 it!
Terry
(This post was last modified: 11-10-2016, 04:07 PM by Radioroslyn.)
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RE: philco tropic model 42-760 - by Radioroslyn - 11-10-2016, 04:06 PM
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