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Philco 37-640 first IF trnsfr help
#4

I am still trying to figure this out.  I took both cans off the IFs and did not see a broken wire so I attemping to use an ohm meter to make sure the coils are ok. The first IF coil, according to the schematic shows one side of the coil going to pin 3 of the plate of the 6a8 tube socket and the other end going to the shadow meter. (But there are 2 shadow meter wires I do not know which one to properly check)
The other coil in the first IF goes from the grid of the 6k7 tube, but there are 3 grids I do not know which one(pin) to test and then connects to ground.   
I hope someone can help.  I am still to new at this to figure this out. Once I get this one, I can verify the 2nd IF.  Thanks,  John 
By the way, I have finally got a schematic file that did not fail so it is attached.  I had to rescan a new version and it worked.  (FYI) the IF transformers in the schematic are parts# 33 and 34.


Attached Files
.pdf 2025-01-10_170457.pdf Size: 1.71 MB  Downloads: 36


Messages In This Thread
RE: Philco 37-640 first IF trnsfr help - by morzh - 01-09-2025, 11:34 AM
RE: Philco 37-640 first IF still need help - by georgetownjohn - 01-10-2025, 07:10 PM
RE: Philco 37-640 first IF trnsfr help - by morzh - 01-10-2025, 10:42 PM
RE: Philco 37-640 first IF trnsfr help - by RodB - 01-11-2025, 10:15 AM
RE: Philco 37-640 first IF trnsfr help - by morzh - 01-11-2025, 08:54 PM



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