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MVS Label Project

Hyper64 ST-V F3 Irem Madonna
Adding a credit button
Freeplay alternative

This is a trick I learned from a friend of mine. It was really intended for other arcade games. On some arcade games if you put the game on Freeplay it changes the attract mode - or the screens that show when the game is not being played. So the solution is to put in a button that will credit up the machine so you get the same screens without having to put in quarters. This comes in handy when you are using your MVS cab for other Jamma games, especially ones that allow for a Continue. The other reason I like this idea, is that you can set up to play a game like Metal Slug and only put in a certain number of credits just to see how far you can get.

You will need a soldering iron,
Wire strippers
Momentary pushbutton SPST switch - I use Radio Shack Cat. No. 275-09A which will give you two buttons.
And this guy. I hesitate to call it a washer, because I have not been able to find any washers with the right inside diameter that the button can fit through without being just huge. What this is, is a Machine Bushing - 1/2" x 14 Ga. I found these at a car parts shop.
Pretty basic stuff. Solder one wire to one side, the other wire to the other side. This is electronics 101.
This is what the button looks like from the outside. Just take out the lock, and add the button.Take the nut and lock washer off the switch. Put the switch and wires through one of the bushings, and then put it through the hole for the lock. Put the other bushing on from the back and put the lock washer and nut on the back.
This is what it should look like from the back.
Here is the only really tricky part. On a Neo Geo machine, the coin mechs are set for each player (and some other games like TMNT). So what I do is run the wires to both mechs. What you have is a + and a ground. On each coin mech you will have the same. Just join the appropriate wires. In my case, I just spliced the + wire into two strands and attached them. The ground is usually common, so you only need to run it to one coin switch.