Diagnosing weird game issues with Gottlieb System 80B (Raven)

Just when I thought I had my Raven running beautifully, it just started acting up. I would press the start button and the game would begin to start, but then not kick out a ball, the sound would stop, and none of the coils would fire. It was very odd. I knew from experience that Gottlieb games can get a bit wonky with irregular power or switch inputs, so here’s a short, 2-part video series of the “rabbit hole” I went down trying to figure out what was wrong? (As always, Ockham’s Razor tends to prevail)

Along the way, we learn a few things about the switch matrix on these System 80 games and how they differ from other manufacturers like Bally/Williams when it comes to trying to trace switch matrix issues. Here’s part one:

And here is part two, where we figure things out…

Upgrading Gottlieb System 80 MPU board with new battery pack

One of the first things you have to do when you get an original Gottlieb System 80 game is deal with their on-board NiCad battery pack, if it has not already been addressed. Gottlieb installed these batteries on the actual MPU board itself and like on other games, it’s a common cause of serious problems with the game. The batteries begin to leak after awhile, releasing electrolytes that corrode the MPU board and the components on it. This can happen even if you don’t see any obvious leaks. The batteries need to be replaced. There are a few options you have to do this: a remote battery pack (3 AA batteries along with a blocking diode to keep them from being charged if they’re not rechargeable batteries), a 2032 lithium coin cell, or my favorite, a 5.5v 1.5F memory capacitor. The memory cap will last the longest and will not destroy any components on the board. It will keep a charge for at least a month or more without power. Here’s a video of me adding this fix to a Gottlieb System 80B MPU


Diagnosing and fixing stuck flippers (on a Gottlieb System 80 and other machines)

I got a new pinball machine in the other day and one of the flippers was sticking up. In this video series I go over examining what was wrong and how to address it. There are a number of causes for stuck flippers. The most common cause is a dirty or worn coil sleeve. Also sometimes there can be a hang up with the EOS (end of stroke) switch (more common on Bally/WMS than older Bally or Gottlieb games).

Adding a memory capacitor to a Gottlieb Sys80 “Jacks To Open”

Now that I’ve got space to pull more of my project machines out to work on them, I’m diving into Sys80 stuff. The first order of business is to work on a “Jacks To Open” machine, which is a solid-state remake of Gottlieb’s popular wedgehead, “Jacks Open”. This game came with the battery removed (or maybe I removed it when I got it – I don’t remember honestly) but the MPU board was in good shape, but the game wouldn’t remember any settings because obviously, there was no battery-back-up.

This is a simple fix, and for these games it makes more sense to add a memory capacitor than a remote battery pack, so in this 4-part series, I go over adding the memory capacitor to the machine. Check it out:

Re-pinning System 80 edge connectors – Gottlieb Mars God of War

I finally found some time to take a look at the Mars God of War I pulled out of a hurricane katrina-damaged house in New Orleans last year. The batteries on the MPU board had hosed the connectors as well as the main board and I am set to replace it with Pascal Janin’s PI80x4 board. In preparation for that, I have to re-pin some of the damaged connectors… as this video shows, things are never as easy as they seem…..