So I had thought that despite the cosmetic issues with the Asteroids Deluxe cabinet it was working ok, but this turned out not to be the case. It started to fail to boot but when it did sometimes the graphics would be corrupted (asteroids all in the same place!) or randomly crash and reset. You can try ignoring these things and hoping it’ll be ok but that rarely works 😅
A clue was when it would fail to boot it would go into a beeping pattern, this turned out to be a test mode 💡
So 1 low tone and 1 high, let’s checkout L1. Hmm clearly a previous repair. A bit of probing around with the multimeter revealed an intermittent A3 address line between these two RAM chips, and that line goes on from L1 to the bank of ROMs. These PCBs are delicate and looks like some tracks were damaged with the repair and even though this is a neat fix it’s not quite 100%. What with time pressures and not wanting to open up a can of worms I patched the A3 trace on the bottom of the board. Seems fine now!
