PCB Repair Logs Nemesis
Nemesis
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| PCB Image | Reserved |
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| Pin Out | Reserved |
Repairer: Arcade King
Forum Thread: Nemesis PCB Repair
Problem: Was fixing a mates nemesis when I decided to pull mine out and test it, what you know bloody graphics problems, basically coloured dots and lines running vertically down the screen.
Put the board away it was doing my head in and came back to it from time to time, problem increased to a error on startup saying Character Ram BAD, when pcb was cold it would boot but after it warmed up if you switched it back off and on again you would get the error. PCB is 2 layers so first thing I did was used Woka's pcb to determin which side was at fault, result bottom video pcb.
Nextswapped over all the customs, all fine.
Fix: The character Ram consists of 8 4416 Drams, I ended up socketing the lot and using my Konami Jail Break (which is the only other pcb i have that uses 4416's) and testing each ram. 4 out of the 8 rams were poo.
Problem: Game loads to crosshatch then resets. This happened while working on the above.
Fix: bad 74ls04 @ 22E Video PCB
Notes:
This pcb has so much different types of ram on it its crazy.
Character ram: 8 4416's
Scroll Ram: 2 6116's D22 and 25
Vram1: TC5533 @ A15 and C15
Vram2: TC5533 @ D15
Sprite: 16x 4164
Sound: 6116 @9A
Program: 6264 @17A and C and 16 A and C
Colour Ram: 6116 @ 14K and 15K
I also reprogrammed my program roms to the set in mame which allows continue, so gay without it.
