Repairer: Arcade King
Forum Thread: Black Dragon PCB Repair
Brad's Original Black Dragon (Tiger) PCB
PCB was missing 2 roms a 27512 @ 9B and 27256 @ 2N
The rom at 2N is for all the in game foreground text and 9B is part of the background.
First things first replaced the 2 missing roms.
Problem: Foreground text is all messed up.
Fix: Pin 23 (A11) on rom 2N was stuck High. Tracked back to pin 2 of a 74ls253 @ 3N. Replacing the chip fixed the problem.
Problem: Character Graphics have faint horizontal lines through them.
Fix: Faulty 74ls253 @ 2K. Both chips were TI (Texas Instruments) branded IC's
Board now 100%
Repair Logs converted to wiki format by Brad from Aussie Arcade.