This pcb was missing the progam roms, so checked the battery and it was dead off course.
Burnt the korean roms and removed the battery.
After that the game played, but only red colour and no sync.
Traced the sync signal back to a bad output on the LS367 @ IC9.
There were some burnt components on the pcb, two resistors and three resistor packs.
Replaced them with help from a scrap World Rally board and patched the video ground trace.
Then all colours and sync were back, but there was too much green colour.
Traced the green signal back to the HCT273 @ic 24, replaced it and we have a fully working board.
I think in some point of time, the monitor crapped out and blew the video signals.
Burnt the korean roms and removed the battery.
After that the game played, but only red colour and no sync.
Traced the sync signal back to a bad output on the LS367 @ IC9.
There were some burnt components on the pcb, two resistors and three resistor packs.
Replaced them with help from a scrap World Rally board and patched the video ground trace.
Then all colours and sync were back, but there was too much green colour.
Traced the green signal back to the HCT273 @ic 24, replaced it and we have a fully working board.
I think in some point of time, the monitor crapped out and blew the video signals.
