Gyruss Help. Bad Graphics.

Cmndr Brain

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I'm having trouble repairing my Gyruss PCB. First off, the game plays with no problems. Just half the graphics are messed up. Originally it had no playfield. To get it to this point, I had two bad 2149 rams @ 7B & 7C. Then all the graphics were messed up, but at least I had a playfield now. I found a bad 74LS377/78 @ 7G and two bad eproms @ 6C & 7C. Reburned new ones and verified all the rest. Now half the graphics are messed up while playing. The inner playfield is messed up, but when the objects cross a certain point in the playfield, they correct themselves. In the second pic two ships are flying out. The inner ship has the wrong graphic, but the outer is correct. Any suggestions?. I have o-scoped most of the chips in the video circuit and they "seem" correct.
 

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