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Prof
24th November 2005, 08:54 PM
Doing a couple at the moment. Might as well post them.


Pengo. Original PCB. Should apply to the bootlegs.

Sound Distorted. Locks up or resets when trying to draw maze. Something starts without drawing maze.

OK, suspect something happening when it trys to play sounds as all sounds are clipped/out of tune. Have a poke around with a logic probe at anywhere where the 2 ciruits meet the data bus, and find a dead 74LS174 with no outputs. Seems it times the 2 busses. Pulled and replaced. Game good to go.

IC 48 at fault. Replaced, game now 100%