Sometimes when you have to do more extensive work to relays in an old electro-mechanical game, you can’t bend over the cabinet. You need to get all those assemblies on a bench to service. I go over how you can remove the insides of a game so you can more easily access the components.
The next video in this series goes into repairing a broken latch relay.
This is a fun video that I think is quite informative. I go over the process of how I discovered a feature in the game was not working. It’s a good example of how even supposedly “fully-working” games are often not fully working and many people don’t realize.
So what do you do when you discover a play feature isn’t working? I go over how we can diagnose and identify/fix the problem, even without having schematics. Check it out!
You turn on your game and… “BLECH!” that’s what you get? That’s not good. Let’s try to figure out what exactly is happening:
Armed with more information, later on I have some time to pull the driver board and diagnose things further:
I was going through some old videos that had been uploaded to YouTube that for some reason were not made public and found this one. It’s a short video on how to go through the diagnostics on these 80s era Bally pinball machines and track down switch matrix issues. I don’t go into how the matrix works in this particular video, but I do demonstrate how a stuck switch can cause odd behavior. In this case, the tilt triggers when a certain target is hit.
This is a game that’s been sitting in the back for awhile at my place that I keep meaning to get to, so I finally jumped back into to figure out what was wrong. It’s weird to go over notes you made 6+ months ago and try to pick back up where you left off — remind me not to do that.. LOL But the issue was relatively simple: The center bank of drop targets was not resetting.
In this series of videos, I go over, step-by-step the process of how to figure out what’s causing this problem, how to read schematics and manual diagrams, and the various points of failure, and once again, we are reminded of “Ockham’s Razor” which suggests the most obvious cause is the most likely… OR IS IT?
Interestingly enough, once I figured out where the problem was, rather than solve it the traditional way, I choose to do a “hack”… basically just to see if I could do it. The choice was, do you replace an entire 16-pin IC that’s only using one small part of it (involving adding a socket and a new chip that is pretty expensive and hard to find) or do you “hack” the damaged chip and piggyback a new component on top of it? Normally I don’t do these kinds of MacGuyver stuff on system boards, but it was a fun trick to try and it cost a few cents and about 10 minutes verses a lot more time than would have been used to replace a whole IC.
One reason why this hack job is particularly sloppy is because I had to work on the board in the game due to the previous owner having hard-soldered some wires to one of the connectors – that’ll be another future project to clean up all that mess, but for now, I needed to get this back working.
To understand what I did, here is a substitute circuit board showing the position of various individual 2N4401 transistors overlaid on the CA3081 IC package. Using this you can figure out where to insert a transistor manually on the IC pinouts if one of them fails:
One of the things us pinball enthusiasts love to do is tell stories about how we acquired games. Each game has its own unique provenance and history, and there’s almost always an interesting story behind them. This is the first episode in an ongoing series were we talk about the stories behind the games and how they came to be. I start the series off with the very first pinball machine I purchased, a Gottlieb “Genie” – before I knew anything about how to repair and restore games. It was the game that got me on this path. I hope you enjoy the story – be sure to subscribe on Youtube! Thanks for watching!
Here are some pictures from early on when I got the game and began to restore it.
This is a fun series of videos of me trying something new. Let’s replace the old gas plasma displays in a Bally 35 solid state pinball machine with new low-voltage LED displays. This reduces the power consumption of the pinball machine and cuts out the high power portion of the power supply board for the display – a whole area we don’t have to worry about any more by switching over to LEDs. The price for this as a kit is quite reasonable (and cheaper than replacing them with used displays usually). But it takes some time and skill to populate your own circuit boards. I’m going to give it a try. Let’s see how it goes!
Here is a time lapse of me doing the lion’s share of the board work:
And here’s the finished product!