Horius

Thats a good idea, I will see if i can get a cheap donor system so i can swap some ic's over.

i checked continuity between all the ics and the sockets and it seemed that isnt the problem. Regarding the bench power supply, the atari draws 350/400mA at 9v (injected at the main filter cap) and shows the same symptoms using a original wallbrick. Time to dig out the service manual and do some trace checking thanks for the suggestions.

There still could be oxidation on the contacts but your mentioned problem does make me think it has somthing to do with the power delivery circuit. Did you test the voltage on the 7805 regulator? I usually measure the equivalent series resistance and the capacitance to see if they are out of spec and replace if necessary.

I own a Retroflag SUPERPi Raspberry Pi Case (https://www.amazon.com/Retroflag-Raspberry-superpi-Shutdown-Version/dp/B07WBVXPXP/ref=sr_1_8?) and I can recommend it. I was looking for a retro themed Pi case and was debating if i would 3d print one. The retroflag case had decent build quality and the safe shutdown feature using the power button works great.

The black and white color image (with bars) seems to me it has somthing to do with NTSC or PAL colour encoding settings.

I recently acquired a 4 switch Atari 2600 trying and I am having some problems which I cannot place. Unfortunately i do not have an old tv which allows RF input, and decided modify the atari with a composite out. This guide was used https://www.thefuturewas8bit.com/2600_comp_mod and the atari was sold to me as "working". When i try to play Pacman I do get an image and the controller works but i seem invincible since touching the ghosts makes them move to the center. Additionally i can not finish the level as the last pill does not dissapear. If i try using an other cartidge (Yars revenge) i get a weird visual problem (shield is missing, white bar on the left, and the "yar" is missing. I have performed the following changes trying to fix the problem. - Replaced all the electrolytic capacitors (2200uF and 2x4.7uF) - the Chicklet cap (0.1uF Film capacitor) near the power regulator - A new 7805 voltage regulator. - Reseating all socketed IC's - Cleaning cartridge slot/switches - Reflowed all solder points on the PCB - Powering the board with a DC bench power supply I was hoping someone has idea's or could point me in the right direction as i think this is a unusual problem :)