pcjohn
Well-known member
- Joined
- Apr 4, 2007
- Messages
- 3,712
- Reaction score
- 582
Had a DOA Space Duel.
No signs of life. Logic probe showed system was watchdogging.
Replaced the AVG - Same thing.
Replaced the CPU - Signs of life ! Coin counter was clicking and board was
resetting every couple of seconds. Powering up in test mode brought 6 low beeps
and 2 high beeps. Control test works (tones when pushing buttons) but still no
picture.
Replaced all 2114 ram. Beep sequence changed but now game controls didn't
play tones.
Oops ! Found solder bridge across a 2114 pin 8 to ground. Removed bridge and
control test now works.
Replaced buffers at B1, C1 and F2.
Powered up and board is fully functional !
This took forever. The chips were a major pain to remove. I found it
easier to clip all the legs then desolder what was left of the pins.
Hope this info helps anyone with a similar problem. It was a decent educational
experience although I hope I don't have to repeat it any time soon.
JD
No signs of life. Logic probe showed system was watchdogging.
Replaced the AVG - Same thing.
Replaced the CPU - Signs of life ! Coin counter was clicking and board was
resetting every couple of seconds. Powering up in test mode brought 6 low beeps
and 2 high beeps. Control test works (tones when pushing buttons) but still no
picture.
Replaced all 2114 ram. Beep sequence changed but now game controls didn't
play tones.
Oops ! Found solder bridge across a 2114 pin 8 to ground. Removed bridge and
control test now works.
Replaced buffers at B1, C1 and F2.
Powered up and board is fully functional !
This took forever. The chips were a major pain to remove. I found it
easier to clip all the legs then desolder what was left of the pins.
Hope this info helps anyone with a similar problem. It was a decent educational
experience although I hope I don't have to repeat it any time soon.
JD