Gottlieb System 3 - Repair!

[Magiske]

Hi,

I am trying to help a friend fix his Rescue 911. (He confused 2 cables = Death!)

So I am doing a step by step repair(Or trying, I am a WPC guy, so no experience with Gottlieb Sys 3)


First step, get the CPU board to boot. I have it powered with 5v and LED is mostly quick flashing, pause, quick flashing. And reading the guide on pinrepair,
it suggests that it's either the battery(read 2.97, so should be good) or U11(MC74HC123AN).
So is there any way of testing the U11 before ordering a new one.

Or any other good suggesting repairing System 3..

/Mads (I will be back, since I suspect the A5 is toast, but that's for another time!)

 

[AlanJ]

test it with a logic probe

 

[Magiske]

test it with a logic probe

Will try. Else I will just try to replace it. Just don't have any spider sense on System 3 as I have on WPC when stuff don't work.

/M