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  #16  
Old 05-11-2016, 09:06 PM
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Radiotronman Radiotronman is offline
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The chassis is 11J27. I appreciate any help!
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  #17  
Old 05-11-2016, 10:40 PM
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Kevin Kuehn Kevin Kuehn is offline
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I suppose if the yoke is shorting you could be getting some high voltage spikes across it. I wonder what would happen if you pulled the vertical output, or the yoke plug, just to see if that keeps things cooler? Someone with more experience than I will know if that's a safe test to unplug the yoke.
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  #18  
Old 05-12-2016, 09:16 AM
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Jeffhs Jeffhs is offline
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If the vertical output tube (or any other) is removed, the TV won't work because, in the Briefcase 19 set and likely the Seventeener line as well, the tube filaments are wired in series. If you unplug the yoke, you might lose the 2nd anode voltage to the CRT.

BTW, I had a Briefcase 19 portable TV, a trash find in my home town, in the early '70s. Worked very well all the time I owned it. Finally retired it when I moved in 1975. IIRC, it still worked, but I had no use for it by then since I had purchased a new 12" b&w all-channel portable to replace it. The Philco set sat behind the garage for some time before I junked it.

Had I known anything at that time beyond tube swapping about restoring old TVs, I would have tried to save it since those older sets, as we know, were built like tanks, even though the Briefcase 19 had at least one PC board (I didn't care for PC boards at that time and still don't to this day after a bad experience I had with one in the early '70s, which ruined a Silvertone CTC12 clone roundie color set I had and liked at the time).

The Briefcase 19 and, IIRC, the Seventeeners were housed in metal cabinets, although the fronts of the sets, which were also the CRT mask, were plastic. I'm surprised the front of my set survived without crazing or outright cracking, although if I remember correctly, it was yellowing by the time I got it--unless it was off-white when the set was new.
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  #19  
Old 05-12-2016, 09:33 AM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
I suppose if the yoke is shorting you could be getting some high voltage spikes across it. I wonder what would happen if you pulled the vertical output, or the yoke plug, just to see if that keeps things cooler? Someone with more experience than I will know if that's a safe test to unplug the yoke.
If there's HV and the yoke is disconnected, you'll burn the CRT phosphors real quickly. If running the set without a yoke, you'll have to jumper the crt heater at the socket to complete the heater string. Leave the CRT out for now, until you find out what's really ailing it.
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  #20  
Old 05-12-2016, 10:36 AM
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Kevin Kuehn Kevin Kuehn is offline
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Would you need to unplug the CRT even with the brightness turned down?
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  #21  
Old 05-12-2016, 11:11 AM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
Would you need to unplug the CRT even with the brightness turned down?
Those CRT's are too hard to get, why take a chance!
You're probably right, never thought of it. I've been doing to this way for ages.
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