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Where's the issue(s) causing these
3 Attachment(s)
So I got the thermistor replaced and it does a better job degaussing, but I'll have to cycle it a number times to see if it's enough.
I started running though some test patterns and noticed two things disturbing. I'm attaching some pictures. In the first pic you can see the upper left dip down. I have not idea how to fix this and it's not noted in the service manual. In the second and third pics, there is some issue with displaying the white lines of the grid. I know the convergence is a bit off, but this doesn't seem tied to that. There are color bands to the left and right of the lines and they appear as though their in motion (from bottom to top). Again, the service manual makes not mention of such and issue. I really want to get the set up and going, but every time I turn around there's another issue or two to address. Thanks for all the help. |
If you disconnect the degaussing coil, does the problem go away?
If the coil current never shuts down completely due to an improper thermistor value, wavering color patterns will show on the screen. |
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The service manual says something about an APC adjustment. IT says to adjust for minimum movement of color bars. I got this set used and it is obvious that someone messed with quite a few of the controls. They might have messed with some of the less common ones as well. |
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I've been trying to compare it to my 19JC55Z chassis CC2. I know it's a couple years newer, but the picture is just about perfect (minor convergence and slightly tilted image). If I can get this one looking like that, I'll be happy. |
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Anyway, I managed to get the drooping upper left back to pretty much level with the right side. Too much adjustment made the right side change and same with the bottom. It was a compromise, but it looks so much better. Thanks! |
Does the fringing dissipate when the color level is turned down? This looks a lot like a pattern generator that is keeping the chroma burst on during a monochrome pattern.
Modern sets have a color killer circuit that prevents this: http://en.wikipedia.org/wiki/Color_killer The explanation here describes how Israel held back on color tv and what viewers did to counter it. Never underestimate the determined viewer. |
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I adjusted the color killer as described in the SM. It said to turn to static channel, adjust control until there is color in the static and then back it off until there are no signs of color. I did this once and noticed that there were occasional bursts of color, so I backed it off a bit more until that no longer happened. Should I try to back it off a bit more? |
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"" That's not true, all color TVs since the CT-100 have had a color killer circuit. They aren't always completely accurate, or adjusted correctly, but that TV definitely has one. If it didn't, B/W broadcasts would be full of colored snow. That pattern generator probably keeps the color burst active all the time. Actually, based on the appearance, I'm guessing he's using a DVD player, or maybe a PC as the pattern generator. ""
Yup I vote for this too ! ! ! |
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luma---> 3.58 notch filter----> to composite mixer chroma---> 3.58 band pass filter---> to above composite mixer And the composite then feeds an RF modulator. |
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