800, Incognito NTSC System Lost color?

[Android8675]

Don't think this is related to the Incognito, but my 800 the other day lost all color. Using a s-video cable to a Sony Trinitron, the 800 has been mine since the 80s, and if I connect the monitor plug to a 130xe the color is fine.

 

Any idea where I should start poking around on my 800 to figure out what the problem is? Tech level 2 out of 5.

 

Alternatively, If anyone wants to part with a 800 in the meantime, I might be interested if the price is ok.

 

-A.

 

[+Stephen]

Don't think this is related to the Incognito, but my 800 the other day lost all color. Using a s-video cable to a Sony Trinitron, the 800 has been mine since the 80s, and if I connect the monitor plug to a 130xe the color is fine.

 

Any idea where I should start poking around on my 800 to figure out what the problem is? Tech level 2 out of 5.

 

Alternatively, If anyone wants to part with a 800 in the meantime, I might be interested if the price is ok.

 

-A.

 

First thing I would check is the colour pot adjustment. I think on the 800s, it's on the back of the case.

 

EDIT - check this post http://atariage.com/forums/topic/177900-atari-800-color-is-green/

[Android8675]

First thing I would check is the colour pot adjustment. I think on the 800s, it's on the back of the case.

 

EDIT - check this post http://atariage.com/forums/topic/177900-atari-800-color-is-green/

System has been running great since I bought it new, just one day the color was fine, I did a power cycle/hard restart and the color is gone, just grey and white. Still think it's the color pot?

 

I'll try fiddling with the pot tonight.

[+Stephen]

System has been running great since I bought it new, just one day the color was fine, I did a power cycle/hard restart and the color is gone, just grey and white. Still think it's the color pot?

 

I'll try fiddling with the pot tonight.

It's the easiest thing to check, and if the pot gets corroded, it definitely causes this issue. Very gently work it back and forth, maybe an 1/8th to 1/4 turn at a time. This pot will NOT turn 360, it has stops, but they are very delicate.

[Android8675]

Tried fiddling with the pot, and it was doing stuff, but the blue background of the ready prompt stayed grey. When I put the system back together it briefly had color (the blue was now magenta, but I understand why that happened), and now the color is gone again. Next possible culprit?

 

End, Fiddled with the pot again and at one end a lot of messed up colors appeared, I tried to find Atari Blue, but it would not come back no matter how careful I turned the pot. Still think this is the cuprit? Maybe I could just replace the cpu card?

 

Argh, it comes and goes, now it's grey no matter what. I think this is going to need professional diagnostics.

Edited July 29, 2016 by Android8675