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Power Supply 37-89
#1

Hi guys,
I've been reading discussions but this is my first post.
I am restoring my first, a 37-89 that has been in the family since new. I have replaced resistors, all tubes with tested replacements, and capacitors (except micas). I had hoped for music but no luck.
I found I wasn't getting voltages on tube sockets. I opened the transformer and found wires had insulation falling off. I spliced each as close to the winding as I could and covered splices with heat shrink. Still nothing but hum.
What should the voltages from the transformer be? The transformer is Philco 32-7583 (with the rectifier 5Y4G on top).

Note: the rectifier tube had been replaced with a 5V4G and I bought a 5Y4G and replaced it. Are the pins the same? Should I suspect the socket has been rewired?
Any help or suggestions will be greatly appreciated, Herb
#2

Herb

1. The information on the tubes is well available on the web, so instead of waiting for answers you could've simply do that:

Punch in "5V4G tube" in google and get this:
http://www.radiomuseum.org/tubes/tube_5v4g.html

Then do the same with 5Y4G and get this:
http://www.radiomuseum.org/tubes/tube_5y4g.html

Look at the pinouts:


You will see right away they are NOT the same.

5Y4G
   

5V4G
   

--------


Now you gotta be careful going back to original because God knows, the man who replaced it might've re-wired the circuit to accommodate the other tube and now the wiring might not work with the original.
#3

Thank you very much for the info. I hope to be able to open it tomorrow and tinker.
I will let you know what I find.
Herb
#4

The socket was still wired for 5Y4G (guess the other tube was just stuck in there). I am getting correct voltages but still not picking up any signals except switches and other interference.

Thanks for the tip, Herb




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