Get molex connectors first between the MPU and driver board and go from there
Don't make it a parts pin. Sinbad is a GREAT game

If you have (basic) soldering skills try LISY1 as a replacement for your MPU https://lisy.dev/lisy1.html

In any case desolder that old 'Datasentry' Batterie as fast as possible.
The leakage of that Battery will things make even worse.

Pascal all-in-one board will cost you $350 or so. That's the route I would go.

Pascal is the only way to go.

Could be a grounding problem between the boards. Suggest soldering seperate
ground and 5v wires between boards and supply. Also make sure the 5v supply
is close to that value.

Sounds like your boards are working, just a poor connection between them.

That playfield looks great. Save it.

I also am a big fan of the Pascal all in one board. Eliminates the interconnect, but you still need to remake a few edge connectors.

Here's the link:

https://www.flippp.fr/pi1x4.php

It sounds like one of the unobtainium spider chips on the cpu board is failing. No choice but to get a replacement board.

All those wires soldered to the boards is considered a hack and should be removed. You will need to get the correct edge connectors and pins from Great Plains Electronics. Then, any replacement boards you get will be unpluggable just like the original boards were.

Have had an excellent experience reviving games with the Lisy boards and they are easy and fun to build. Saved a Charlie's Angels last year which had no head (cabinet and playfield only) with a Lisy1 and buying a head and other boards from eBay and local pinball friends.

Have also successfully used Lisy80 and Lisy35 with friend's games. These are my go-to boards when debugging a game with a broken MPU because switch matrix, solenoid and lamp testing is all supported through the web interface. They do take ~30 seconds to boot though.

I find reviving system 1 MPUs is a futile waste of time - Lisy1, Ni-Wumpf and likely anything else will be more reliable . Anyway, Sinbad is a great game, is deserves to be saved and enjoyed!

Hey son, don't be so cheap. Just buy the Pascal board and be done with it. Just kidding, I know you're a starving college student. Good luck with your first project machine.

Anyone looking for a "Sinbad" project pin? If so, PM me.

Well yeah, but where are you?????

Myrtle Beach,SC
I might have a block on that in my settings, I will look into it later, thanks for letting me know. If you want more info please PM me so we don't tie up the guys thread