rmcelwee
Member
I'm a novice but have repaired a few of these lately. On this one the board was a complete mess when I started. Now when it plays there are no ghosts or pac. Here is a picture of the title screen. I have looked at a lot of stuff (so much that I do not remember). The last thing I replaced was the 74ls139 @ 7M and RAM @ 2D. Any guidance would be appreciated.
Oh, I found some notes that said I had pulses @ 3E pin 1, 4, and 5. No pulse on pin#2 (swapped the 74LS20 and no change). I had pulses on 3F and 3H (pin 5,7,9,11). 5N pin 4, 5, 6 are pulsing. Pin9 on 1E and 2E are pulsing.
Oh, I found some notes that said I had pulses @ 3E pin 1, 4, and 5. No pulse on pin#2 (swapped the 74LS20 and no change). I had pulses on 3F and 3H (pin 5,7,9,11). 5N pin 4, 5, 6 are pulsing. Pin9 on 1E and 2E are pulsing.
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