How to test bridge rectifiers (in pinball machines and elsewhere)

The other day I was working on a game and traced the problem back to a blown bridge rectifier, so I thought it might be nice to produce a short little video on how to test/check bridge rectifiers in pinball machines, as well as a little info on what they do.

Diagnosing problems with Mist Multiball mechanism on Bram Stoker’s Dracula

Diagnosing problems with the mist multi-ball assembly on a Bally/WMS Bram Stoker’s Dracula pinball machine. In this case, we were not getting power to the motor, which is supplied from the 20vdc circuit on the power driver board (which also powers the flash lamps). In this series of videos I show how to test the mist motor, and where you check for power and back-trace it to the driver board, then identify which components are related to this problem and how to fix it.

Building replacement LED displays (from a kit)

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!

Upgrading eddy/proximity sensors on Bally/WMS games (Theater of Magic)

Recently I decided to replace the trunk eddy sensor on Theater of Magic with something more reliable than the original Bally/Williams proximity sensors. They are prone to “drifting” and will need regular adjustment. There’s a company that makes an auto-adjusting board that I wanted to try out, so here is my video showing the installation of that new board. This should make the game a little bit more reliable.