How to make a test bench rig for Bally-18/35 MPU boards using a PC power supply

I found this old video the other day and realized I didn’t have a post on my main site showcasing this video so I wanted to add it (also, this was before I learned the proper pronunciation of “Bally” LOL…. bah-lee).

How to add a switched power outlet to your pinball machine

These days modding games is all the rage: adding fancy toppers, custom lighting, subwoofers and powered speakers and more. But many pinball machines don’t have a facility for you to plug in extra stuff in your game. Many games do have a “service outlet” inside the game, but this is what’s called “un-switched” meaning it’s on all the time – mainly so technicians can use a soldering iron on the game with the power off. In this video I go over the process to tap into the switched power lines of the game to add your own extra outlet(s) that come on when you turn the game on.

How to work on electro-mechanical switch stacks on pinball machines

Switch stacks are the primary parts of electro-mechanical pinball machines, triggering game activity. I go over in this video, how they work, the different types of switch configurations, and how to clean and maintain them so they work reliably.

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All about connectors: Molex, sizes, tools, pins and crimping

Pinball machines (as well as other arcade games) use a wide variety of wires and connectors. The most popular brand of connectors is called “Molex” which is a specific maker, but also a generic term often referred to as the plug/un-plug style connectors you will find on everything from power supply wiring to board connectors.

In this video, I go over the most common sizes and types of connectors you’re likely to find, what tools are available and how to rebuild and re-pin these connectors.

Making a pinball board test rig using a PC power supply

Here’s a quick video that shows how to take an old PC power supply you may have laying around and use it to power up pinball boards for testing. I use the Bally-35 MPU board as an example of how we can set this up to do board work on the MPU while it’s outside of the actual pinball machine. This is great for testing things while you’re refurbishing a board that’s been giving you problems.

Securing and adjusting stand-up targets and their leaf switches

On many games such as this Theater of Magic, there are stand-up targets in the middle of the playfield that take a constant beating from the ball. The switch blades in these targets, as well as the entire assembly will often get bent out of position and stop registering. I demonstrate how to use a simple tool to fix the leaf switch blades and put them back into position, as well as some other techniques for making sure the targets are solidly-attached to the playfield.

Stand-up targets have changed very little over the decades so this technique works on both old and new pinball machines.