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Philco 37-89 Ist IF
Radioroslyn
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#4

05-01-2024, 09:25 AM
Mostly the difference between the '37 an '38 model chassis is the conversion to octal from standard based tubes. I suspect that the loop is used to add a little bit feedback to the IF amp stage. This in turn boosts the gain. A lot of pentode IF amp tubes the suppressor grid and cathode are internally connected so this sort circuit couldn't be used. Phasing is important without it no feedback will happen
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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Messages In This Thread
Philco 37-89 Ist IF - by dconant - 04-30-2024, 05:40 PM
RE: Philco 37-89 Ist IF - by Radioroslyn - 04-30-2024, 09:07 PM
RE: Philco 37-89 Ist IF - by dconant - 05-01-2024, 08:08 AM
RE: Philco 37-89 Ist IF - by Radioroslyn - 05-01-2024, 09:25 AM



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