SEGA System 16b Suicide Repair:
I had the opportunity to buy a not working SEGA System 16b Motherboard with E-Swat ROM board from the Czech Republic for £90GBP and it looked in great condition from the photographs the seller provided:
Solder side also appear to be free of any re-work:
So I decided to take the gamble and it arrived this morning.
Upon testing it is of course dead as advertised:
There is a stable sync, a mostly black video output and no sound.
When I bought this I suspected the Hitachi FD1094 68000 CPU which contains a battery to hold program encryption keys may have died.
So I removed the FD1094:
Replaced it with a regular 16mhz x68000:
I swapped the ROM board over to the previously repaired E-Swat ROM board I and tested the board again:
Edit:
It appears the suicide battery is not actually dead and runs fine. The problem appears to be on the ROM board itself. To be investigated further…