One thing I have found with testing system 1 power supply is that everything must be plugged in to everything else to test output voltages. Unplugged gives wrong or no values.

That's wrong. Because it's AC, you want one lead on pin 6 and the other on pin 7. Meter on AC voltage. You're seeing half the voltage now, so it should be about right when you test correctly.

When testing the output of the PS board, leave J2 and J3 connectors off, as Clay recommends. Readings may be a little high, but Clay's guide accounts for this. On the J3 connector, some voltages can be read using the cabinet ground while others need the ground on the connector. If your readings are off, check your ground.

I'm a huge fan of reusing old boards whenever possible. I rebuilt my location Genie PS board twice before I finally gave in and bought a newer (way better designed) board. Don't bother rebuilding yours. Get one of the upgrade boards. My factory CPU and driver boards are rock solid after doing the recommended ground mods. The PS board is by far the weakest link on system ones.

Plug in J1 and test your outputs. Leave J2 and J3 disconnected. Watch your ground, as I mentioned above.

I'm assuming this game isn't a reimport. If it is, stop and get a schematic to check the wiring first.

If your output voltages are good, don't worry about the input voltages. The CPU and driver boards don't care about the input voltages for the PS board, just the output voltages. Now connect up the CPU board and continue as Clay suggests.

The voltages you measured are fine.

The High voltage (69V) uses a full wave bridge rectifier type circuit (4 diodes) with no ground reference going back to the transformer -- so you must measure AC voltage directly across pins 6 and 7 to get 69V (or 72V in your case).

The 12VAC to supply your low voltage (12VDC to feed 5V regulator) uses a full wave center tap rectifier circuit (2 diodes). This supplies a ground connection back to the transformer which is connected at the half way mark within that transformer winding. For that type of circuit, you measure both pins 1 and pins 2 separately with the black lead on ground. You *could* also measure AC voltage directly across pins 1 and 2 but will end up with a 2x reading --> 24VAC.

The 14VAC to supply power for your -12V supply -- same thing. It also uses a full wave center tap rectifier circuit (2 diodes) with a ground connection back to the transformer. Again, the proper method to measure this one is with respect to ground -- black lead on ground and measure pins 4 and 5 separately. And again, you could also measure the AC voltage directly across pins 4 and 5 and end up with a 2x reading --> 28VAC.

For description of the two types of bridge rectifier circuits used on that board --

Center tap:

Bridge:

OK -- that is a negative supply... To filter a negative supply they would connect the positive end of the capacitor to ground and the negative end of the cap to your negative supply. For this one, turn your leads around.