Pal Atari 7800 picture quality problem

[tajume80]

I am having a problem with my pal Atari 7800. The screen flickers randomly and has a massive ghosting issue with 2600 and 7800 games.

 

I had the same problem with rf, and I thought that was the problem. Then I s-video modded the console and I am having the same problem.

 

Most of the colours are off and tweaking the pots does not help with the issue.

 

I wonder, could the motherboard be the problem, or is some chip problem?

 

I have modded my ntsc 7800 and the games look fine.

 

I have also tried different power supplies and s-video cables.

Edited April 28, 2019 by tajume80

[ongikong]

Mhh... that sounds strange to me, as the 2600 and 7800 modes use different graphic-chips.

Did you check your motherboard for bad capacitors or solder points ?

 

Did you tweak the pots of your mod or on the motherboard?

Maybe a pot is defective?

Did you also check another TV/Monitor? Some monitors might not like the offered S-Video signal...

[tajume80]

Yes, I tweaked both posts on the motherboard and also the on the the mod.

I've tried three different tv's and all of them show the same problem.

 

As you said, it sounds strange. The thing is that most of the 2600 games look awful and if you try to get the right colours the ghosting gets worse.

 

Other case is that 7800 games either look ok (but still with wrong colours) or really bad (overblown whites and wrong colours).

 

I'm suspecting that something is wrong with the motherboard. Before the modding the picture flashed between black & white and colour.

 

I'm having bad luck with my pal 7800's. I have bought two of them and both of them have problems Now it seems that I have to buy a third one and hope it will work without problems.

[mimo]

It may be a silly question, but have you tried a different TV? preferably a CRT set?

[tajume80]

Yes I have. Same problem