Quoted from andre060:
My thought was this kit is expensive, and I can probably make my own for way less once I understand how the Stern kit works.
Here is the wiring diagram of the entire unit, as I understand it. I created that based on a mod a user sold me, which was soldered with individual wires and not a PCB.
A video of the re-created kit is here:
The photo shows it after removing all the hot glue. I tore off a connection but resoldered it according to this diagram and it works perfectly. The round unit on the right is the headphone jack, with jack facing downwards. The top unit is the incremental encoder with knob facing down as well.
Would you be able to figure out details on the incremental encoder used? If so, it would be easy to buy. The ones I found (STEC11B13) require 5V power - will those be OK?
Wiring diagram for CN13 (resized).png
The reason behind all this is that in Europe we have coin doors without the dollar bill hole. We simply can't mount the official kit. My approach would be to place the volume knob in the plug for the tournament button. The headphone jack would come out the coin return with a loosely hanging cable, as I dont want to drill my cabinet or coin door.