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  #1  
Old 04-14-2018, 06:48 PM
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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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Old 04-14-2018, 07:32 PM
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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 !
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Old 04-14-2018, 09:41 PM
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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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Old 04-15-2018, 10:52 AM
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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 !
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Old 04-15-2018, 03:06 PM
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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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Old 04-15-2018, 04:30 PM
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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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Old 04-15-2018, 05:15 PM
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Ok, I can eyeball it close to good but things have a green outline for some reason, I can turn the color level to zero and people on screen have a green outline.
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Old 04-15-2018, 05:42 PM
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Are you familiar with convergence (static convergence)?
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Reading between the scan lines since the mid 2000's.
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Old 04-15-2018, 05:54 PM
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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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Old 04-15-2018, 06:37 PM
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Quote:
Originally Posted by Laserdisc View Post
Ok, I can eyeball it close to good but things have a green outline for some reason, I can turn the color level to zero and people on screen have a green outline.
Well done so far.
First get the grey scale close as you can. Warm up set 1/2 hr. Turn down color all the way. No signal input. Put the service switch to service. Using the three color controls ( R-G-B ) turn up one at a time til you see that color line
Back off until the line just goes away. Repeat for other 2 colors. When done you should see no line or a very dim one.
Flip switch to normal. You should get B&W snow. If it has a tint to it
tweak the controls a little to make it as B&W as you can. If any controls
cause a sudden change you may have a bad control. No big deal it was
a common fail.
Next your problem. Sounds like convergence. If the green outline is fairly
constant at different brightness thats it. Now it gets hard to describe but
when it "clicks" its EASY !
On the CRT you have the yoke, convergence panel screwed onto the plastic yoke cover. Last on the neck is the blue lateral / purity ring assy.
Now a few IIRC's. On the convergence board are 9 controls & 3 coils.
Ignore them. Also there are 3 sections 120 degrees apart with thumb wheels. The top is blue, others are red & green. The thumb wheels move
the colors in & out toward the center of the CRT & you need them to
overlap.
Now color all the way down. Either a dot generator OR a source with very
small stationary areas such as writing in the CENTER of the screen.
Turn the R or G thumb wheels & see effect. You may only have to move
the G thumb wheel.
Try that but dont turn them too much so its easy to go back. A little
playing should give you the idea. Only concentrate on the CENTER !

good luck
73 Zeno
LFOD !
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Old 06-09-2018, 03:59 PM
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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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Old 06-09-2018, 05:16 PM
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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 05:30 PM.
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Old 06-10-2018, 09:06 AM
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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 !
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Old 06-10-2018, 10:01 AM
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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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Old 06-10-2018, 03:51 PM
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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.
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