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From what I've read in the past, band #2 oscillator coil is often found to be bad on the 37-116, I know mine was!
Ron
Bendix 0626. RCA 8BX5. RCA T64
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Didn't want to hear that!!! I had resistance checked all the coils and they seemed ok. That will necessitate disassembly of the tuner chassis again. What a pain! Oh well. Part of the process, part of the fun!
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Same on my 37-116. It's annoying but I don't honestly miss it that much in terms of listening.
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You haven't lived until you've had one of those RF units apart a dozen times or so trying to chase down an intermittent (or otherwise) defect.
I don't think I'll ever buy a multiband 1937-38 Philco again. ![Icon_thumbdown Icon_thumbdown](https://philcoradio.com/phorum/images/smilies/icon_thumbdown.gif) Some of them look really great...but the RF units are too much of a pain. For me, anyway.
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Ron Ramirez
Ferdinand IN
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Ron, you're so encouraging! Looks like I'll be in the process of getting a life as it is the oscillator coil. I thought I checked that but maybe it went bad in the process of getting things back together.
Nathan, I thought about just leaving it as there isn't much there to listen to. However, there are couple of stations that I do occasionally listen to on the upper end of the broadcast band and need that range to get them. Besides, I'm this far and want the whole thing to work. So, the unit will come out and the coil removed and rewound. I rarely back away from a challenge.
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Sorry, just being honest.
There have been several times when I have checked those band 2 oscillator coils on the bench, they checked good for continuity, only to fail to oscillate when everything was hooked up and powered on. Replacement is usually the only solution. There used to be someone who could rewind those coils. I never could successfully rewind one. I'll bet Brenda D. could; Mike (morzh) also.
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Ron Ramirez
Ferdinand IN
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As I recall they are only 33 turns - that is 11 X 3. I have yet to find one that was good.
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Well, it will come apart this afternoon. Sounds like it may be a challenge!
Russ, have you rewound one of these?
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Hopefully you can rewind the band #2 coil. I was lucky in that the band #2 oscillator coils are good on my 37-116 & 37-690---there is plenty of activity on band 2 such as WWV, CHU & amateur radio transmissions + the upper part of the AM band (at least in my neck of the woods) Ken
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I've never rewound any coil before but I gave this 37-116 a shot. Took me three attempts to get it to oscillate. I can get the low end and high end of the dial to work with alignment but the center in between goes deaf, it's not tracking well. After listening to this SW band on other radios, I saw where there wasn't anything much on it anyway so I let it be. Wasn't worth the hassle of taking that tuner apart a fourth time! Good luck with yours!
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84
(This post was last modified: 02-11-2019, 02:59 PM by 462ron.)
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Congratulations! Great job!
Now please tell us how you did it. Wire gauge? Number of turns? Winding direction?
You may encourage me yet to try again...
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Ron Ramirez
Ferdinand IN
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Thanks Ron! I used 35 AWG wire. Both windings are wound clockwise looking at and starting at the terminal end. My counting gave 13 turns between terminal 1 and 2, 14 between 2 and 3, and 11 between 3 and 4. These numbers and 35 AWG wire produced resistances as listed on the schematic. The secondary was also 11 turns and is wound over top of the section of the primary that is between terminals 3 and 4. I don't know if that is important but that is how the original was wound. You can see on the pic of the finished coil the direction of the wind - clockwise.
As I said, it is possible that the first winding should have been 14 rather than 13 since I had to add 100mmf to the compensating cap #42C to get the dial lined up. Or, the wire spacing was different as when I measured the original wire, it indicated that it was 36 AWG, which I didn't have. Prior to adding the cap, I couldn't adjust 42C tight enough to get the low end of the dial on the right freq.
I'm thrilled that it worked cuz I didn't want to take it apart again!
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Good (so I was close).
I would suggest that anyone doing a recap perform this rewind 'caus you are going to need it sooner or later.
I have a spare chassis for my 37-116 all done and ready to go. It came from the radio that had cracks on the right and left radius.
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I am so impressed that you rewound that coil! Awesome job.
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