Hi all, I have finally added a system 1 to my collection, but when I purchased it, the scores were out. This game has new score boards and the PI-1 X4 board in it.

After quite a bit of research, this is what I've done in an attempt to diagnose the issue:

1. Checked pins 7 & 9 on the transformer. They read 73VAC, which is a bit high but seems fine to me.

2. Checked A2P1 pins 6&7 and they also read 73VAC, so it sounds like the high voltage circuit is working fine.

3. Checked A2P3 Pins 1&5 and get only 1.5VDC instead of 60VDC.

4. Checked A2p3 pins 3&5 and get only 0.61V instead of 42VDC.

5. Checked A2P3 pin 7 to A2P1 pin 5 and get 5V instead of 4, but this should be fine.

6. Checked A2P3 pin 8 to A2P1 pin 5 and get 8.38V, which is perfect.

This is where i'm stumped with online resources. I don't have a schematic or manual for the game, and pinrepair only offers "The 60vdc and 42vdc power lines come from the 69vac bottom board voltage" for info on the DC not being there.

Also, I did read in another thread that there are fuses that look more like capacitors on this board. There is a light brown one near the 60v LED. I pulled it and tested for continuity and didn't get any. I'm thinking maybe the 73V blew this fuse?

I've also read that the power supply has a pot to adjust the high voltage. Is this true, and if so, where would I find it?

Any help would be greatly appreciated.

Bump for evening crowd. Anyone?

Thanks guys!

So could I jumper slow blow fuses of the same amperage to test, or are these fuses special in some way?

Also, is the 73VAC okay? Or will that keep blowing it?

Ha, I missed the logic issue there.

Anyway, I don't remember, but don't they make a .1A slow blow? I'd have to look at what I have. Assuming I can match it, can I jumper it? Sounds like I may want to error on the side of caution.

Sucks that they didn't put the little cylinder fuses on the board so that average pinheads might have the parts on hand. It's a pain to wait for fuses to come in the mail.

Looks like I need the .100A (100mA) fuse. I tested it again to be sure, and sure as shit, she's pooched!

I'll report back when I get the fuses in the mail. I'm going to disconnect all displays and add them one at a time.

Picture below is for future pinheads that might need a reference.

fuse (resized).jpg

Hey, can someone post the exact part number for the 100mA fuse that I need for the board? There are several choices when I look at the tiny fuse site. Mouser and digikey appear to carry all of them, but I'm not sure which one to order. I emailed the guy that builds the boards, but I'm not sure when he's going to get back to me. I'd like to order the fuses today if possible.

Thanks, I sent him an email, so hopefully he'll get back to me this weekend. I'm assuming that the differences in the fuses are just lead lengths, but I want to be sure I'm ordering the right ones. Strange that the part number is not listed on his website or in the manual.

Pascal got back to me, and it looks like I ordered the wrong fuses. Bummer.

Here is the part for future reference.

https://www.digikey.com/products/en?keywords=486-2002-ND%20

Update: Board is up and running. Just needed the fuse.