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Philco 40-201
TFB
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#1

02-18-2018, 11:53 PM
I am working on a Philco model 40-201 (should be electrically identical to a 40-195).  I have found an extra part (resistor) in the unit, it appears to be factory installed. There is a 4700 ohm resistor in parallel with the secondary of the short wave oscillator coil, see attached illustration. I am not smart enough to know what this does.  Comments from the experts will be appreciated.


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Radioroslyn
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#2

02-19-2018, 01:17 AM
Well I'm not sure exactly why it's there but it lowers the Q of the osc secondary. I would leave it in the circuit as it was probably added to correct a problem from a earlier run that isn't documented.
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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TFB
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#3

02-19-2018, 08:25 PM
Radioroslyn,
Thanks - I think your comments make sense.
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