26 replies to this topic

[Blackegg13]

I'm realy sorry for resurecting so old topic, but I'm getting desperate.

Last couple months I was trying to convert my 6 switch Atari 2600 to work over composite video. I had tried few mods and only one worked with bad video quality. I was considering buying ready one, but they are all from US and I'm not sure if they will work on PAL console. One from this topic was last one I have tried. I have redesigned board that mamejay have posted here to accommodate screw terminals.

My problem now is fact that picture I'm getting is black and white. If I connect chroma to output directly I got colours but with rubbish quality. If it's connected to terminal on mod board there is no colour. What I'm after is where I got it wrong. I have attached diagram I done and 2600 motherboard diagram with points (green) where i connected wires. Red crosses are the elements I removed.

I will appreciate any help. I'm not electroinc pro but I'm comfy with solder iron.

Thanks

[alex_79]

I think you must leave the two pullup resistors (R212 and R208 in the schematic you posted), because TIA has "open collector" outputs. Anyway I'm not an expert as I wrote in the first post and I don't have the modded junior anymore so I can't help you very much to track down the problem.