Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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: 65


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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Tim, I have some bakelite sockets in my work shop that I can dig up. I believe quite a few are NOS. I will take photo...RodB — 10:03 PM
Philco 610B oscillator wiring
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM
HiFi (Chifi) tube amp build - but my own design.
Tim; I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM

[-]
Who's Online
There are currently 1658 online users. [Complete List]
» 2 Member(s) | 1656 Guest(s)
AvatarAvatar

>