Capcom Tiger Road arcade pcb repair
This game had every second scanline missing in all the sprites.
A lot of arcade game games work by using two line RAM buffers for sprites – the sprite logic builds line N+1 in RAM0 whilst line N in RAM1 is displayed to the screen, then they swap and RAM0 outputs to the screen whilst the new line is built in RAM1 and so on.
So a missing scanline in sprites suggests one of the RAM chips in the double buffer has failed. By piggybacking good RAM onto the chips on the video board I found the fault right away. The lower line buffer RAM had failed. A new one was soldered in and game fixed.