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Defender wasn't running, fixed power supply and decoders. Ran for a day, came back to it the next day and it was down. Found out a 7474 wasn't processing the clock right, got it back up. Came back to it a couple of days later and now I have vertical lines that change colors with the Defender logo/mutants in game.

No RAM errors, no ROM errors, good Decoders, good ribbon cable... Just really starting to reach the end of what I know with this game.

Shorted pin 23 on the decoder to flip the screen for player 2, lines were still there. People insisted it was the 165s, I ran the board on the bench and couldn't see anything obvious, socketed and replaced them all anyways. So, it's not the 165s. With the 165s socketed I tried it with all different combinations to see how the issue looked with certain ones removed... I noticed that the pixels were the lines are were black during the rug... and AWLAYS present, didn't matter which of the shift registers were removed, the lines were always there.

I SHOULD be getting some new headers in the mail tomorrow so I can check again with my decoder boards, but the lines were there with the original decoders and my replacements.
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