(Also posted to a FB group that I frequent.)
So I dug back into my work pile and pulled out a Konami Kicker board. Was tagged with “graphics issues.” Powered it up to see that it would produce a whole lot of stuck pixels horizontally across the screen.
Also noticed problems with scrolling – parts of the screen that should not scroll horizontally, like the very top of the screen where player scores, high score and lives are shown, would scroll sometimes while parts that should scroll would not. Sometimes, this would also cause a complete absence of all sprites, and all you get is background and text. Pushing on the large custom near the center of the board seem to change the behavior so I replaced the socket.
This ended up having no difference, so I felt around the board looking for warmer chips, and I discovered that when I ran my fingers across one of the smaller Konami customs near the corner of the board, it would change the behavior.
Wiggled it, pushed on it, and hit it with freeze spray, but that actually did not make a difference. Looking at nearby chips, I discovered one of the ’32s near it (at B14) that would completely change the behavior if I touched its pins. I piggybacked a replacement ’32 on top of it and it fixed the glitches. Clipped, desoldered, socketed, and replaced the ’32 and the board is working again.
Also worth mentioning that an 74HCT32 works in place of the 74LS32 in this case, just in the event you do not have an exact replacement. This was an easy one – wish they could all be that way.