Bought off ebay unknown status
Some 2114s are missing
Board has TONS of chips socketed and replaced!
Visual inspection shows the crystal is broken off
Reset switch leads are shorted together
One 74LS367 had a chip with legs bent, fixed and re-inserted
- Snipped off extra wire length on reset switch
- installed new 12Mhz crystal
- Pulled ROMS and verified, they are asteroids version 2 ROMS
- One rom had a pin break off
- Installed 2 new 2114s to replace the missing ones
- tested 3 game code ROMS with Fluke, OK
- tested memory region 0x0000 0x03FF with fluke long test, OK
- tested memory region 0x4000 0x47FF with fluke long test, OK
- game boots up now but display is messed up, parts are OK others are all over the place
- Used HP10529A logic comparator, found 74LS191s at C9 and D9 were stuck high pin 6, replaced
- Sounds work great, except "thump" sound, which is more like a click, click.
- Found .22uf capacitor @ C35 was missing, replaced, sound works fine now.
- Game works now.