I spent a bit of time with Missile Command swapping out all of the EPROMs, the 6502 CPU and the pokey (a custom sound chip) and stil get the same results after powering it on. There are two RAM chips that have quite a bit of corrosion. My guess is they are the culprit. Unfortunately, I’m not comfortable enough with my soldering abilities to install new RAM sockets so the board is being mailed out today for repair. The turn around is going to be two weeks. Stay tuned….