Tonight’s lesson for me in vintage arcade collecting: Just because I’ve owned a game for 16 years doesn’t mean I’ve ever really gone through it.
My Robotron had developed intermittent RAM errors after many reliable years. Sure, one of the 24 (!) RAMs might have gone bad, but it seemed equally likely to me that the power supply was probably getting flaky. I got about 4.7V across a cap on the computer board, and after reseating a couple connectors (not a proper fix, I know) I got 4.9. Good enough, and the RAM error is gone.
Looking around, though, I saw this. This is part of the transformer strapping in the main power connector. Why were the wires cut? Why are the wires just twisted together? Why does only one wire have electrical tape? Why is the electrical tape applied wrong? The only answer I am sure of is why the electrical tape is falling off: because electrical tape is terrible. Maybe there were wire nuts on here at some point, but I doubt it. Some of the crimps were not great, either.
The power supply still needs some attention, though. There are some other suspicious splices and a bypassed connector. Oh, well; for now, it’s playing fine.
A decade ago, I tried to put one of Clay Cowgill’s multigame kits in this cabinet. It never worked correctly and I took it out. I wonder if the +5V was a little low even then. Perhaps I should give it another shot.
Edit: A year later, it turns out this wasn’t what was dragging the +5V low. I suspect the bridge rectifier was out. But this was still bad 🙂