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Philco model 70 rebuild - by Tim P.
#79

Ok, I just moved my signal tracer tracer to the plate of the IF tube and connected through a small cap - now it tracks the radio! I can also hear the static through the signal tracer (it is more sensitive than the radio), so I'd say I have it narrowed to the IF stage, maybe more specifically, the IF transformer. I will do some careful checks in this area, but the only thing I see on the plate circuit is the primary of the transformer (#20). Sounds like it's time to pull the IF transformer. To double ck, I went back to the IF grid with the tracer - same, does NOT track the radio and I dont hear the static. I double checked the plate and cathode voltage (no changes), but this may be such a small change that it affects the signal, without affecting a measurable voltage. Just to post, plate sits at 305v, cathode is at 10.6v, G2 is 119. I still have the volume control bypassed with a series of fixed resistors. Thoughts?

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Philco model 70 rebuild - by Tim P. - by TV MAN - 01-29-2014, 11:46 AM
RE: Philco model 70 rebuild - by Tim P. - by TV MAN - 04-26-2014, 10:19 AM



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