Hopefully someone can help. I have a Bally Paragon I'm working on and the voltages are too high on the rectifier board. I have rebuilt the reset circuit on the MPU (acid damage) and installed new proms/roms (I jumpered the board correctly, I have checked and rechecked). I also rebuilt the rectifier board with all new components. The MPU does 6 flashes, but I can't get it do the 7th.

I installed a known working rectifier board and transformer into the machine and got nearly the same voltages, so I have ruled out those components. I am out of ideas though and any help would be appreciated.

Here are the voltages (all connectors attached to game):
TP1: 6.42 VDC - Should be 5.4 VDC
TP2: 258 VDC - Should be 230 VDC
TP3: 15.08 VDC - Should be 12-14 VDC
TP4: 7.13 AC - Should be 5.7 to 7.3 AC
TP5: 54.5 VDC - Should be 43 VDC

Here are the voltages with J2 only connected to the Rectifier board (isolated from the rest of the game):
TP1: 6.44 VDC - Should be 5.4 VDC
TP2: 186 VDC - Should be 150 VDC
TP3: 13.16 VDC - Should be 13-16.5 VDC
TP4: 7.45 AC - Should be 5.7 to 7.3 AC
TP5: 46.3 VDC - Should be 43 VDC

Any ideas what I should check next?
Thanks!

TP3 on the MPU is 26.1 VDC, it looks like it should be 21.5.

The machine is set for 115V. It can be set to 120V as well according to the manual. I will check my wall voltage and see what it is.

Thanks for all the help so far guys.
I switched my transformer over to 120v from 115v since my wall voltage was 123v. That brought down the voltages slightly.
Here are the voltages (all connectors attached to game):
TP1: Was 6.42 VDC is Now 6.05- Should be 5.4 VDC
TP2: Was 258 VDC is now 246- Should be 230 VDC
TP3: Was 15.08 VDC is now 14.26 - Should be 12-14 VDC
TP4: Was 7.13 AC is now 6.8 - Should be 5.7 to 7.3 AC
TP5: Was 54.5 VDC is now 51.8- Should be 43 VDC

R113 and R16 are reading normal resistance.

I checked IRQ line from u9 to the pias, it is ok.

Tried 2 different U10 chips, didn't work.

I hooked up my logic probe and got a low voltage pulse from U10 Pin 18.

I took voltage readings after switching the transformer to 120v
MPU:
TP1: 5.15 vdc - should be 4.9 to 5.2
TP2: 14.13 vdc - should be 12-14
TP3: 25.2 vdc - should be 21.5
TP4 ground
TP5: 5.15 vdc - should be 4.9 to 5.2

Solenoid driver board
TP1: 5.19 vdc - should be 4.9 to 5.2
TP2: 185.7 - should be 190
TP3: 5.12 - 4.9 to 5.2
TP4: 250 vdc - should be 230
TP5: 14.18 vdc - should be 12 to 16.5

Lamp driver board
TP1: 5.21 vdc - should be 4.9 to 5.2
TP2 ground

So it's still not working. I'm thinking about soldering in a new U10 socket? Should I?
Any other ideas or things to check?
Thanks for all the help so far!

You're the man! I unplugged the sound board and the machine fully booted. Do you know the diode # on the soundboard that failed, I know I will find it but if you know it off the top of your head that would help me out. Thanks again!

CR3 was bad. I replaced the diode and reflowed the solder on the sound board pins and it fired right up! I still have a few more issues but I should be able to figure them out. If not, I know who to ask!

Thanks again everyone, especially barakandI.
I don't know if I would have figured it out by myself.
Pinside rulez.

So after getting the machine to boot up, I am having a few more problems. My start button will not start a game. I have traced the wires up to J3 connector on the MPU and they are fine. I can start a game by grounding the red wire on the start button. Once the game starts the first player score will score but then reset to zero while the game is playing. It will count up a bit, then reset to zero over and over. I also noticed when I add credits to the game I will click it numerous times and it will stay at 1 credit, then sometimes it will count the credits up but will then reset back to 1 credit. For example, I'll add 3 credits and the 4th it will go to 2, then 3, then 4, but instead of 5 next, it will reset back to 1 credit.

I am going to re-pin the J3 connector on the MPU, but I have to order the parts. Any ideas what else it could be, besides possibly J3?

I figured out what was going on with the Paragon machine (with help from barakandI, thank you!). It turns out it was a bad 5101 RAM at U8 on the MPU board. I had put in all brand new chips on the MPU board, so I didn't really suspect that at all. Turns out not all "new" chips are functioning!

Hope this helps someone in the future.