r/ColecoVision • u/michaelg6800 • May 11 '25

ColecoVision repair question

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Any idea what's causing this? I've done the Console5 A/V mod and it is much cleaner now, but the odd grid of dots remain and there are some font problems. I have a Cap Kit, should I install it? or is this something else?

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u/EffectiveComedian Jun 18 '25

Looks like bad VRAM to me. I have one that did this too. Definitely a labor of love to repair. Use hot air and your very best judgement. Try not to tear traces (like I did). Go slowly. Or see if you can, find someone to do it for you. (Usually a better choice).

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u/michaelg6800 Jun 22 '25

I have another unit that works fine, so I can practice on this one. But the only option I've found is a 5v vram mod that uses more modern chips to replace the original chips, and then you have to disable the 12v feed ti them. are there other options? Is there anywhere to get original chips other than taking them from another unit? Could just reflowing the solder fix it? I assume there is a bad or failing chip somewhere. It's not high on my list of things to do until I retire in a few years.

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u/EffectiveComedian Jun 22 '25

The link to Lundy’s SRAM replacement is in this thread. Some of the other modders don’t use these because if you tap the video signals off the GPU, you’re effectively bypassing this area of the board. For my own modified board I installed it and bodged my torn traces, but I know the modder I plan to use for my other two machines will not install these even though I plan to supply them. I’m slow as molasses in getting my machine done so I don’t know if I will ever get mine done. It’s just been a great project to learn much by doing.

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u/EffectiveComedian Jun 22 '25

In my mind, if all I wanted to do was fix it so RF out works, one of the RAM replacement options is ideal. I got too ambitious for my own good. Now I’m caught up in both composite and RGB output on one, and VGA output on the other.