Adding Select Game switch to Astro City?

Ok, so I'm trying to add a Select Game switch to an Astro City cab with a 4 slot MVS mobo. My plan is to use a momentary pushbutton SPST switch, similar to the credit button mod on HardMVS, then drill a hole in the center of the control panel and mount the switch.

After reviewing the pinouts for the 4 slot MVS as seen on HardMVS, it would seem that all I need to do is tap pin 26 on the harness for the "Select Up" signal and run a wire from there to switch, and then run another wire from the switch to any of the grounds on the harness (A/B/1/2 and so on).

Sound good? Any objections or corrections? I'm somewhat familiar with this sort of thing, but reading electrical diagrams and the like is far from my strong suit.

Lastly, how do I figure out which side of the harness plug is A/1 and which side is f/28? lol.

Thanks in advance!

That'll work, I'd probably just wire the ground to the same ground lines used for your buttons. The top of the jamma connector aligns with the top of the PCB, so you can figure out pins that way.

^^I would also advise getting your other ground from inside the cp. Most likely from the other ground harness, but if not, you can wire it to the screw somewhere in your CP that has the large green wire attached to it.

NGT said:

^^I would also advise getting your other ground from inside the cp. Most likely from the other ground harness, but if not, you can wire it to the screw somewhere in your CP that has the large green wire attached to it.

Click to expand...

"other ground?"

Isn't there only one ground running to the switch I'm installing?

Or did you just mean that I could/should run the ground to somewhere on the control panel?

Thanks for the advice/help guys!

He's talking about field ground which should be hooked up, if not it would be wise to hook it up. But if your house has old wiring then it wouldnt matter.

Old houses in America don't have an earth?

Correct. At least mine didn't when we added on an extension. Of course the new extension has but the original does not.