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Disassembling 37-650 RF Section Question?
#1

I'm working on a Philco model 37-650. By the way it's nice to be back. I've been restoring radios for about six years now and have come a long way since I last visited here. The Phorum appears to have changed a bit (I think) so bare with me as I get used to all the new stuff. Or maybe I was just gone too long.
I need to get into this RF section to change out components and do a thorough cleaning. Someone really chopped this set up even leaving paper caps down inside this section because they couldn't get them out. Capacitor blocks that still had readings within tolerance but new caps were installed in parallel/series with these blocks etc. Real mess. Here's a pic of the RF section. I hope I did it right.
[Image: http://speakeasyradios.com/yahoo_site_ad...02_std.jpg]
The shaft that goes through all of the bandswitch wafers is secured by a plate on the front of the RF section. I removed the two screws and it appears as if this shaft wants to slide straight out. I understand that I'll have to be careful to not disturb the clocking and the wafers are individually held in with their own hardware. The whole RF section looks like it comes apart in order to get to everything. Question is does this shaft slide straight out without messing anything up? Obviously my first 37-650. Worse Philco RF section I've worked on was a 46-480. Had burned components under it so it had to come out. What a bear. At least there's room here to navigate.
Thanks much,
John

"It's Nice To Be Nice To The Nice"
Major Frank Burns Mash 4077th
#2

Yes - once you remove the two bolts, the band switch shaft can be pulled straight out.

Be careful - once you remove the bolts, do not turn the band switch shaft as you remove it!

These sets are a real pain to work on, but yes, the RF deck must be disassembled to get to all of the paper caps.

--
Ron Ramirez
Ferdinand IN
#3

Actually it is no disaster if the wafers get rotated. On the shaft hole in the wafer is a little V notch; each wafer has this notch. The end of the shaft has a very small raised lump that keys into these wafer notches. With reasonable care in reassembly, you can't screw it up.

Pete AI2V
#4

Thanks! It's coming apart and it's not the worse one I've worked on. As I said there's plenty of room in there so you can at least see everything. I think the real care will be watching the coils that are connected to the bandswitch. I don't like repairing broken coil wires.

John

"It's Nice To Be Nice To The Nice"
Major Frank Burns Mash 4077th




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