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Philco 42-340
#1

I have a Philco 42-340 that I have recapped and replaced 2 tubes, everything else looks good.
when powered up all I get is white noise up and down the dial so I stated checking IF coils and all looked good until I got to #32. The one side White and Red I read 32 ohms but what would be the other side Green and Blue I show open. Now this has one of those compact units PC51 (#32 B, C, D) that has a resistor and two caps. I suspect the resistor is open and nothing in the papers I can find gives me a value. I do read  400pf  each for the two caps. I have no idea what the resistor would be? I'm using the Schematics from 340 and 345 as the latter is much better quality and they seem to be the same in this. 

http://www.nostalgiaair.org/Resources/519/M0013519.htm     
http://www.nostalgiaair.org/Resources/521/M0013521.htm
#2

That resistor is typically 47k.

Update:
Hi, I just checked four Philco schematics from 1942 that have that identical circuit and all four have a 47k resistor.
#3

Rod,
Thank you, 
I think I will splice it in and leave the Caps alone and see if that works
#4

Ok turns out the resistor was ok, someone had done a bad job soldering leads on decades ago so when I started making checks at the terminals instead of through the leads I got 52K so I decided to just put new leads on and reassemble. It still did not work so I started checking resistors and not that there were a lot of them but probably 75% were 30-40% or more out. So I changed them and the radio plays fine.

Thanks for the help!

Eric
#5

Best you find those problems sooner than later.




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