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Philco 37-89 questions??
#2

Hi & Welcome to the Phoum!
Don't know about the agc line. Ron or Chuck would be in the know on that. As for for your rf choke it is NOT a RESISTOR.Rf chokes are design to limit the flow of rf energy. The amount of inductance will determine the frequency it will limit or block. Sorry lately I've had a few folks that think that chokes are measured in resistance. They are not! They are measured in MH or mh not ohms. Most schematics use a resistance measurement so that the repairman can tell if it is shorted or open. What you need to know it the inductance of the choke. Once that is known then you can find a suitable replacement. A very common value for SW radios is 2.5mH. The current rating isn't very critical as rf amp doesn't use much current. Back in the old days used to make my own. 300 turns of small magnet wire on a wooden thread bobbin.
Good luck w/it
Grumpy 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 it!

Terry


Messages In This Thread
Philco 37-89 questions?? - by Richard Moore - 06-07-2011, 11:50 AM
Re: Philco 37-89 questions?? - by 7estatdef - 06-07-2011, 03:29 PM
Re: Philco 37-89 questions?? - by Richard Moore - 06-07-2011, 05:13 PM
Re: Philco 37-89 questions?? - by Ron Ramirez - 06-07-2011, 09:00 PM
Re: Philco 37-89 questions?? - by Richard Moore - 06-12-2011, 09:00 AM



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