joemagiera
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Got an Sega/Gremlin/Data East Astro Fighter that's having problems. The schematics can be found here: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Astro_Fighter.pdf. I never did board repair work before and since even a fully working boardset for this game isn't worth much, I figured this would be a good place to give a first try.
It's a 4 board stack in a cage with an additional interconnect PCB on the cage. Only 3 boards actually plug into the cage, the 4th board sits on top of one of the boards and is connected to it via a cable. I have a known good boardset to test with, so I can swap boards in and out one by one.
I'm having a hard time identifying matching up the actual boards to the schematics, but the two boards I'm having trouble with are the one with the crystal & dip switches and the one that plugs into the main wiring harness and has 3 adjustable pots on it. Both of these boards display the same problem. The game coins up and plays and controls and sound appear to work, but the display does not have video sync. It's like the vertical or horizontal hold is not working.
If you had any ideas where to start or what might cause a "no video sync" problem, please let me know.
It's a 4 board stack in a cage with an additional interconnect PCB on the cage. Only 3 boards actually plug into the cage, the 4th board sits on top of one of the boards and is connected to it via a cable. I have a known good boardset to test with, so I can swap boards in and out one by one.
I'm having a hard time identifying matching up the actual boards to the schematics, but the two boards I'm having trouble with are the one with the crystal & dip switches and the one that plugs into the main wiring harness and has 3 adjustable pots on it. Both of these boards display the same problem. The game coins up and plays and controls and sound appear to work, but the display does not have video sync. It's like the vertical or horizontal hold is not working.
If you had any ideas where to start or what might cause a "no video sync" problem, please let me know.