Trying to bench test this board, applying 12VDC to J3 pins as Clay's guide indicates, LED not turning on. Checked reset line with logic probe, was high and then LED turned on. Now it sometimes comes on solid and sometimes not at all.

Ideas? Anything besides 12VDC needed for bench test?

Have schematics and verified hookup is correct. Sounds like we both had the exact same experience, either locked on LED or nothing at all.

Something else that's interesting is I consistently get three flashes when the board is in the game. So I'm thinking something is up with my bench test approach, but it seems so straight forward according to Clay's guide.

I only have the Vidiot Deluxe board on the bench, no other boards connected to it, so it must be failing after the second flash when installed in the game, meaning there is an issue with the VD board not booting. Which check ROMs again (already re-burned them all once).

Reset circuit appears to be working properly.

Progress - CPU (U3) is not running, either is bad or crystal is bad, no signals on pins 38 or 39.

Issue was bad CPU chip (6809 at U3). Replaced and boots up fine on bench.