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#1
11-28-2013, 09:56 AM
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No vertical sweep question
My vault find (It's literally been in the company vault for 60 years!) experimental Delco car TV has a good looking 15KHz horizontal sawtooth and 7KV anode voltage. But, I'm not finding a 60 Hz signal in the vertical circuits. In the absence of a signal (nothing to sync to), shouldn't there still be a 60 Hz oscillation?
In other words, there should be a raster even without sync pulses, right? Update on project: I had to strapped two Heathkit IP-17 power supplies together to get 200ma @ 250V for the B+. (The original B+ supply was on a separate missing chassis. 250V is an educated guess.) I'm in the process of tediously reverse engineering a schematic. I have a CRT now, but I don't want to install it until my scope says all the circuits are working. (No point in staring at a bloomed horizontal line.) Bobby D. Newbie to TV and Tubes 
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#2
11-28-2013, 11:03 AM
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Welcome to vintage TV restoration!
Sounds like a very interesting find. Post some pictures when you can. Yes you should have 60Hz sawtooth in the vertical. Could be that the vertical oscillator isn't running or a problem in the output stage. Without a schematic, it will be a bit more challenging. You will probably find the problem is a bad paper or electrolytic capacitor. It is usually best to replace all of these troublesome caps, typically called a re-cap. Good luck and keep us posted.
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#3
11-28-2013, 12:35 PM
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Not only paper caps, but plastic-coated paper (aka bumblebees or Black Beauties) and flat molded paper caps with plastic shells (aka Micamolds). This article has photos and descriptions of the culprits:
http://antiqueradio.org/recap.htm Until you have replaced those and any electrolytics, it's a little fanciful to expect a 60-year old TV to work correctly. Phil Nelson Phil's Old Radios http://antiqueradio.org/index.html
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