A friend bought a color classic ii and recapped it. It works but display isnt steady not stable. Any ideas where to look!
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Color classic flicker in display
- Thread starter imactheknife
- Start date
Ok, sounds good.
Not sure if it did, will ask. All is recapped. Logic and analog board
I’d agree about Byrd’s reflow suggestion, but also check the caps used themselves.. I’ve found the CC to be very twitchy with non low ESR caps, so if they’re just run of the mill caps it may cause odd behaviour.
Check that all of the ground clips on the motherboard are present and clean. They are the little rounded tabs that clip onto the motherboard.
So i reflowed the analog and checked over the board again. I am not sure if i did this but the screen has a red tinge now. Screen still flickers lol.. so not really winning at this point.
Definitely check the grounding clips then. That's exactly what mine did. Also make sure your internal cage isn't bent so the clips are making good contact.
See this post:
See this post:
if you have issues with flicker, especially when you tap the analog board with the back of a screwdriver, then you can assume there is a mechanical disconnect, these can be hard to find, and unfortunately the PCB quality of the analog board is really low. I have had an issue like this where the main switch-mode transformer was not soldered in right, I would suggest to re-solder all transformer pins carefully. if the issue is not affected by tapping on the analog board and the neck board (gentle taps) then it's something else, considering the change in colour, you may want to check under the bottom shield where you will find the main controller chip and the video amplifier, the video amp should be re-soldered, and some times it helps to re-solder the trim pots, the heat can improve connections inside them. if you have further colour trouble then ill do my best to assist, i just wrestled one of those.
What causes the red to bleed off edges?
It means the RGB guns are not aligned properly, this can be caused by focus (found on PL1, the big red trimmer) or on top of the CRT there are 2 trim-pots, they also influence that shift. if that doesn't work, check your CRT neck's convergence rings, these are not easy to adjust by any means, first check if they are marked with a white line, if so, and the line is still intact, best not play with it, if you can see that the line has shifted on some of the rings, and you are up for the significant challenge of adjusting the CRT while on, having your hands near high voltages while looking in the mirror you placed in front of the CRT, then you can also adjust those. (Best reserved for those with experience)
So, in summary:
- check focus trimmer first
- check the 2 trim-pots on the yoke on top of the CRT
- check if someone messed with the convergence rings
- adjust these if you feel you can do this safely
these settings are totally separate from your screen adjustments, so there is no use to messing with any of the pots in the back of the analog board. Hope it helps, and best of luck!
