Years ago I bought a 2 1/4″ trackball on eBay for a pittance. I’d forgotten all about it, only finding it a couple days ago in a box of other stuff.
Glad I did; the original on this needs a serious rebuild as the bearings stick and the rollers are so worn you pinch your fingers constantly. This one has nearly *no* wear on it at all, plus handles like a dream. I need to swap a couple input wires as the up/down are backwards, but that’s it.
I got a Centipede JAMMA adapter off eBay. Since the cab is out back, it really helped to be able to try things out and be able to test in the house instead of having to trudge out back and haul the kids out with me every time I wanted to test. Plus, it cost me next to nothing.
I found one cap I neglected to replace the first time around. Replaced that.
Next, touched up the solder on the RAM I replaced. No change.
Then I went to town with the solder, touching up every solder joint that even remotely looked bad. And now I have the game back with no glitches.
I’m still getting a 4 FF error. I replaced the 555 since I had it in hand and the iron was already hot. Rules that out. Of course, the EAROM itself may be bad. Since the game itself works without it, I’m not so concerned. It just won’t save high scores.
Now I have to finish up the darn coin door.