Atari 2600 colors unstable

[Jamisonia]

I already connect without an RF switch.

I opened up the Atari, cleaned the contacts thoroughly. I connected a piece of quad shielded coax cable with an F connector to RCA straight to the female RCA jack the Atari video cable is connected to. Same issue. I notice the problem is better, though not totally alleviated which I switch the Atari to B instead of A on the channel select switch. This is weird, because it does not appear to act as a 3-4 switch as moving this switch does not allow the Atari to appear on any other channel besides 3.

I will try cleaning the switches next.

[Hobie-wan]

If you're feeling adventurous, take the shielding off the bottom shielding and see if the chip at the bottom is socketed. If it is, carefully pry it up a little, then push it back in in case one of those pins is not making good contact since that is what generates the picture.

[Limewater]

I already connect without an RF switch.

I opened up the Atari, cleaned the contacts thoroughly. I connected a piece of quad shielded coax cable with an F connector to RCA straight to the female RCA jack the Atari video cable is connected to. Same issue. I notice the problem is better, though not totally alleviated which I switch the Atari to B instead of A on the channel select switch. This is weird, because it does not appear to act as a 3-4 switch as moving this switch does not allow the Atari to appear on any other channel besides 3.

I will try cleaning the switches next.

This is getting more puzzling now. When you say that the color changes randomly, do you mean it's like a switch being thrown and the pallet just changes in an instant, or do the colors just kind of shift in a continuous manner before fading?

[Ziggy]

Did you take a look at all the caps on the board to see if any of them look bad? That's definitely worth doing.


For $25, you can get the unassembled mod kit from here: http://longhornengineer.com/atari-av-mods/

This mod takes the video signal before it goes to the RF circuit, so if it's the RF that's causing the problem, this would take care of that. $25 for the PCB and all the components needed is a great deal in my opinion, and the mod is pretty straight forward. Looks really easy. I've been meaning to get one myself.

[Majors]

For $25, you can get the unassembled mod kit from here: http://longhornengineer.com/atari-av-mods/

I'll second that. But in my adventures, I had a bad 2600 motherboard that I spent hours trying to the the mod to work on. As a test, I installed the A/V mod in another 2600 and it worked perfect the first time. On the first PCB, I did install the Chris Cracknell mod over a year ago...I think that did something bad to the board. Moral of the story, if you start w/ something bad...it'll still be bad after the mod.

There is that color pot (dail) on the board...you can play with that.

Hate to be the dick on this thread, but can you just buy another 2600?

[KDub]

Can you get any pictures? I don't think everyone is picturing the problem the same way.