Hi, I just modded my colecovision by replacing the vram chips and making the 5v only modification. This CV is also AV modded.
When I turn it on everything works perfectly, but after a few seconds the whole screen becomes garbled. See video below.
I assume that the vram chips are fine, and the kind of corruption does not look like what is usually experienced with failing ram (I refer to the screenshots in the technical manual).
I have cleaned the power switch repeatedly, so for now I would exclude that as well.
I have also tried to use a second power supply, and I get the exact same symptoms.
Thus my focus is now on the VDP failing. Given what you see in the video, would you replace it? I have two spare VDP chips, just wanted to hear second opinions before starting (another) surgical intervention.
Edited by zCRP, Wed Aug 9, 2017 3:49 PM.