I am having problems with my system 80 power supply. I am not getting enough voltage (3.5) out of pins 1&2 on J2 as well as pin 7 on J3.
I also tested pins 1 and pin 3 on J3, and while the voltage is a little high (+3%), it seems to increase every minute or so by .1V. I do not know if this behavior is normal as I only have the input to the power supply connected.
The reason I am working on the power supply is because all displays do not work (rest of machine works - machine boots, sound works, pop bumpers, scoring,etc., only displays do not work)
The work described above is with the existing power supply that was with my machine when purchased.
As a second step, I tried a new power supply. Everything tested well. With scores disconnected, machine powered up. I was able to start a game. I have a Pink panther, so the display (credit and ball count) on the play filed was working.
When I later connected displays (power off machine first), I blew the rectifier (I believe this is the part name) on the power supply board. It almost caught on fire!
I sent out the new board for repair, so I am experimenting with old board (i had it tested and replaced defective parts) as I want to use it as a back up.
Any advice would be greatly appreciated!
This is all new to me, so it is definitely a learning experience!