I just picked up an Atari 2600 Jr and a 7800 console. I got them for practically nothing so I wasn't expecting perfection. They were dirty as hell too.

Upon testing both of them, they work (signal and sound), however the video quality is fuzzy/wavy. I have tried a few different cables as well a cleaned them a little hoping for some improvement. It helped a bit, but not enough as these problems are most likely internal.

Aside from a composite mod. What would actually be required in going about restoring/improving the video quality? I know this isn't a 1 step process and I'm not asking for a guide. Just would like to know, is this a test and replace capacitor deal, or would I have to buy all new parts for these systems?

Or would it be more worth it in the end to forget about as it would be to costly?