Author Topic: Picture/Sound Question (Read 2026 times)

npschre · « **on:** November 22, 2016, 07:34:52 pm »

Does this look like a monitor issue or a ROM issue? I'm already planning on a cap kit regardless as it curls up on the left side after being on for a bit. After warming up, the lines go away and then flash in and out in pieces.

I've also got a constant high pitch sound after I reseated the ROMs. When the high pitched sound isn't piercing my ear drums, I'm only getting a few of the sounds. Walk/jumping is there, but mostly everything in between is missing.

Any advice is appreciated. Thanks guys.

Sock Master · « **Reply #1 on:** November 22, 2016, 08:51:00 pm »

It's definitely not a monitor issue. It looks like the character ROMs are bad or not reading correctly, or something in the logic related to character graphics is going bad. Maybe try reseating EPROMs 3P and 3N on the bottom PCB.

The high pitch sound may be bad sound ROMs, or the sound CPU not executing it's code correctly. (The walk and jump sounds do not rely on the sound CPU, so they will work even if the sound CPU is not.) Maybe try reseating EPROMs 3F and 3H on the top PCB. It may also be possible that these two chips were accidentally swapped with one another.. If the EPROMs still have their labels, they will be marked with 3F and 3H, and the silk screening on the PCB next to the sockets will also be marked 3F and 3H.