The PHILCO Phorum
37-630 coil removal and repair. - Printable Version

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37-630 coil removal and repair. - Forrest - 11-12-2020

Hello I’ve got a 37-630 with an open primary on the rf coil # 9 first it was static then opened all the way.  Looking at it looks impossible to get out I think I have to remove the gang switch shaft then remove the plate it’s mounted on, if and when I get it out has any one rewound one of these?  Schematic says it’s 130 ohms.  # 36 wire?
See photo with screw driver pointing out coil.
Forrest.

RE: 37-630 coil removal and repair. - rfeenstra - 11-12-2020

I've rewound the osc. coil on a couple of 37-116's, but not the RF coil Hopefully your problem is on the connections to the terminals. To get at it, I did have to disassemble the unit. It's a bit of a pain as there are quite a few connections to the rest of the radio that need to be disconnected before the tuner assembly can be removed. The wires from the coil the switch are short so would be very difficult to remove just the coil. Here are some pics of the unit disassembled from a 37-116 and a 38-116.

https://philcoradio.com/phorum/showthread.php?tid=20788 post #3.

https://philcoradio.com/phorum/showthread.php?tid=19530 posts 1 and 2

https://philcoradio.com/phorum/showthread.php?tid=21139 post 11

RE: 37-630 coil removal and repair. - Radioroslyn - 11-12-2020

I'll mention a couple of things. Not sure how you checked the coil (may have been thru the band switch). Would check the coil at it's connections  to be sure it's the issue. It could be a problem with bad bandswitch contacts. neither is a picnic.
36ga might be a bit of an over kill. Current wise something closer to 38-40ga would work and it would be shorter. 40ga =160' 160 ohms. 36ga is over 300'.
There is an alternative to rewinding that would be adding a rf choke from pins 1 and 2 and a small mica cap from pin 1 to 3.

RE: 37-630 coil removal and repair. - Forrest - 11-12-2020

Hello,
Thanks to both of you for your replys. Rfeenstra fantastic pictures and helpful info.
Terry any ideas on size of Rf choke and small cap?
Forrest.

RE: 37-630 coil removal and repair. - Radioroslyn - 11-12-2020

I'm not sure what value would be best for the choke but would take a stab and say about a few mhs @10ma or more. The cap would be just several mmfds 5 or 10 would be good.