Quick search on the internet didnt come up with anything so I figured I'd post this.
I was prepping a Galaxian board to do the 8-in-1 mod just because I've never done one. Board boots, will coin up and play but only has stars on the screen. Quick probing at the graphics ROMs shows me no activity on pins 6/7/8 on either ROM. Following the trail backwards I eventually find out that the output signal at 5c pin 9 is dead. Not hi, not low, dead. Piggy back another 74LS74 on the IC and the board came to life.
Its still missing some sounds though.
I was prepping a Galaxian board to do the 8-in-1 mod just because I've never done one. Board boots, will coin up and play but only has stars on the screen. Quick probing at the graphics ROMs shows me no activity on pins 6/7/8 on either ROM. Following the trail backwards I eventually find out that the output signal at 5c pin 9 is dead. Not hi, not low, dead. Piggy back another 74LS74 on the IC and the board came to life.
Its still missing some sounds though.
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