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#1
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1975 CCII stopped working
I picked up this 1975 zenith chromacolor II today for cheap, worked ok not great at the sellers place. The tube seemed kinda dim and it progressively got brighter to a point over the course of about 5-10 minutes and stopped with a slight pinkish hue. Got it home, blew out the dust and cleaned the customer controls and now it's got audio, high voltage, nice and stable,but a blank tube. It's like if the brightness was all the way down because with that at max you can catch bits of super dim picture occasionally and it has faint interference as you change channel. Also has the usual CRT power down flash/picture shrink/I'm not sure what to call it but the thing they all do. Please help because I was finally really close to having a working chromacolor II.
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#2
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Check the vert fuse near the vert module ( 9-92 or 9-147) first.
ONLY use exact value, 400ma fast blow IIRC. The module may also be bad. The 9-147 is a sub for 9-92 but better built. What happens is if the V. out has DC on it the picture is pulled off the screen & you only see some foggy looking blotches from the few electrons hitting the screen. Usually at turn off you see the brite "no vert sweep" line followed by the usual color blotches. The line usually pops up from the bottom or down from the top. The first one I had was a real head scratcher......... Also happens to Maggys of the same era ( ch#'s T991 & T809 ). 73 Zeno LFOD ! |
#3
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Ok, it decided to put on a show for the camera. The blue semblance of picture was not something it did to this degree before. https://youtu.be/IRqSsYeymxE
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#4
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OK not the vert.
Looks like its loss of video. Most likely a problem on the 9-88 board. I would clean the tuner before it drove me nuts. Also the service switch on the chassis ( not the one on the 9-86). Check the 4 lead cap thats strapped to the H out heat sink. If its orange you are OK. If its white get a new one before you work on it. Part ## is 800-860 IIRC. Often on e-bay. 73 Zeno LFOD ! |
#5
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Some suspect joints on the 9-88. Waiting for the iron to heat up now. Cleaning module contacts and service switches in the meantime. Orange you glad it's not a white cap? I know I am!
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Audiokarma |
#6
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Boo-yah! Thing works great after reflowing some of the 9-88 and replacing a couple of caps on it because I had them. What's a good way to adjust the color pots on this? It's still had a red hue and I was able to get it better by turning the red down but the picture is still dim overall and not quite "right" color wise by eye.
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#7
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Are you familiar with convergence (static convergence)?
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#8
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I'm familiar with the concept but not actually doing it. I guess that would cause that problem huh?
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#9
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At long last, something has been done with it. I traded it to Sealtest and it did nothing but ride around in his car for months in the Tennessee heat,then he traded it back to me for something else and we did a complete grayscale/static/dynamic convergence tune up (we both used it as a learning experience) and it's now a great looking picture....one minor gripe though. It's kinda "wobbly" from time to time, predominantly when you have just recently turned it on. Not like a hold issue but something else.
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#10
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And now the stupid thing just shut off and won't turn back on, like a blown fuse.
Edit: ok it was the built in breaker,my question is why did it trip after an hour or so of use? Last edited by Laserdisc; 06-09-2018 at 04:30 PM. |
Audiokarma |
#11
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Breakers can get weak from age BUT.
Its more likely the oil filled cap. If it shorts breaker pops. If it opens the pix will pulsate. Quite a few are turning up bad after near 50 yrs ! 73 Zeno LFOD ! |
#12
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That's the infamous "motor start" cap isn't it. Lovely, is there any reason why it couldn't be replaced with a motor start cap of the same specs?
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#13
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A few months ago I went to the local washer and refrigeration parts house and got a 4 mfd run cap and it got my 17" CCII running perfectly again. This is a part I expect to fail on CCII's.
__________________
"If you wish to make an apple pie from scratch, you must first invent the universe." -Carl Sagan |
#14
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Ok,new question. How on Earth do you read one of these caps?
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#15
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Pull one from a parts set if you got one. Every CCII, most
flat chassii, every 1st gen S-3 & all pre S-3 13" sets have the same one. Maybe it was TUD but someone got it from an AC shop. It had OEM numbers also the Zenith ## and everyone I noticed were made by GE. |
Audiokarma |
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