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Old 01-10-2018, 09:41 PM
Crist Rigott Crist Rigott is offline
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Today I worked backward through V9 the Ratio Detector, V8 the sound IF, V7 the Video Amp, V6 the video detector, V5 the 3rd Video IF, and V4 the 2nd Video IF. All that's left is V3 the 1st Video IF and the Tuner.



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Old 01-10-2018, 09:53 PM
Crist Rigott Crist Rigott is offline
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BTW, I got a original Sams Photofact for this TV. It's Sams 59-2. I scanned it and sent Steve at ETF a compressed pdf copy that is much better than what's up there now. Looks like Steve did some further compression and the copy isn't all that good.

Never fear. I've uploaded the full resolution pdf in my dropbox. You can enlarged it at least 400X and it is still very readable. Here's the link. Caution large file @16Mb.

https://www.dropbox.com/s/o0f1yge36v...059-2.pdf?dl=0

Last edited by Crist Rigott; 01-10-2018 at 10:01 PM.
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Old 01-11-2018, 10:00 AM
Crist Rigott Crist Rigott is offline
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OK, I have a concern that I need cleared up. There are these ceramic capacitors used in this TV, mostly in the IF stages. I call them "Hot Dog" caps because they look like hot dogs. Seeing they are ceramic I haven't paid too much attention to them when I do a recap. On this chassis I'm down to the last tube, tube V3, and decided to check some of these caps because they were already disconnected while I'm replacing the resistors. Well, to my amazement the 5 I checked were well out of tolerance......I think.

According to the the Sams parts list, C12-C16 (the ones I checked) can use Aerovox 1468, Cornell-Dubilier 1W series which both are mica caps. I looked in the 1951 Allied catalog and the C-D mica caps have a tolerance of +/- 20% while there was no tolerance listed in the Allied catalog for the Aerovox caps.

In the picture of the schematic below I have penciled in the readings I get for each capacitor. They are:
C12 - 1623pf
C13 - 1431pf
C14 - 1931pf
C15 - 1707pf
C16 - 1230pf

Should I check all of those hot dog caps and replace them too? I've never replaced those before because I've always thought they were good. Now I'm not so sure.




Last edited by Crist Rigott; 01-11-2018 at 10:09 AM.
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