stern/bally mpu-100

[swamprat96]

Got a dead hot hand that has an MPU with the led stuck on. Replaced the basics in the reset section which appears to work but still no joy. Looking for either a good working replacement board or a used alltek replacement for the right price. Or if someone repairs these let me know

Also checked voltages across the board. Got a good 5v and 12v and all the main chips have power and ground where they should. I suspect a bad 6800 or 6820 or both and as they are $50 inc shipping and rare its not worth the gamble
Tony

[Strangeways]

I'd try replacing the 40 pin sockets on the PIA's and CPU. Could also be the ROMs.

have you followed Clay's repair section on the MPU board ? Sounds like you are nearly there.

Sponsors might stock some of the parts you need, or you can try Ed at Great Plains electronics. His shipping is much cheaper than anywhere else O/S.

[studley67]

i repair these boards for my own use,however i do have all spare chips.i also upgrade,jumper the boards to take the larger ,readilly available roms.pm me if i can help.regards damien

[Skybeaux]

I also repair any problems with these type of boards.
I'm on the Central Coast at Summerland Point so may not be far from you.

[swamprat96]

thanks guys. I'm close to Skybeaux so I'm taking the board to him. Also ordered some 6800 and 6821 from futurlec so I have stock next time

Cheers

Tony

[Strangeways]

Ken will sort it out for you in no time