12v in or 12v out?

[Spaz Monkey]

So I'm working on a major rewiring project of my cab.  I have multiple boards in the cab and I'm able to switch games by turning the 12v and 5v off at a switch.  Looking over Bob Robert's JAMMA Pinout, I see he runs "F" from the cab to the lights for the coin door.  My question is, what happens if I change that from running from the board to the door to from the power supply to the board?

[modessitt]

My question is, what happens if I change that from running from the board to the door to from the power supply to the board?

I was following you until I got confused there at the end.

Do you mean you want to hook your coin door lights up to the +12 that is going to the board, instead of directly from the power supply?

Or do you mean you want to disconnect the +12 from the lights and attach it to the board to get the +12 there?

Or something else entirely?  What exactly is your problem?

[Spaz Monkey]

I knew I didn't describe it correctly.  The "F" wire on a JAMMA harness carries 12v.  Bob Roberts takes this wire and runs it from the harness to the door (or how I said it, "from the board to the door").  What will happen when I take "F" from the door and attach it to the power supply ("from the power supply to the board").

[modessitt]

Okay, I went and read BobRob's instructions and figured what he's talking about.

It seems that whatever board he is using has continuity between the top and bottom +12V pads without the JAMMA connector attached.   Knowing this, he can use the 2nd +12V wire as an output to the coindoors to supply the +12V for the light, meters, etc.  I believe all JAMMA boards are like this but I would check to make sure your boards have the same continuity betweeen the top and bottom pads of the edge connector, and if so, do it just like BobRob says, if you want. 

He only does it this way because he wants to keep it neat and not run a wire to the coin door from the power supply.  The only concern is that +12V goes to two pads on the board to ensure a good connection with the +12V source.  It is a lot less unlikely to lose contact with that source with two contacts instead of one.  If this concerns you, you can either solder-attach a new wire to one of the +12V wires near the connector and send it to the door in the bundle, or just run the +12V to the door from the power supply.

[Spaz Monkey]

Just woke up and haven't had any caffinee so please pardon my translation of what you just said.  In BobRob's example, the board pulls 12v off either 6 or F.  Bob is using F to power the door, but he could have easily used 6.  He's using the harness because he's already running wires from it to the coin mech.  He could just make another wire to power the door from the power supply, but that would require him to make another wire. 

[modessitt]

Correct.

[RayB]

Power goes to the pins from the wires.

Power doesn't come from the board connected.

[modessitt]

if both 6 and F are connected thru the board, you can send 12V into pin 6 and out pin F to another location.  It would be the same as +12V to both pinf 6 & F with a jumper attached to pin F.

Ideally, you'd want both pins 6 & F to have 12V supplied by the power supply, and another wire to the coin door, but if neatness is important in a spot most people will neer see, then do the BobRob thing.

[ChadTower]

If you're going to power something not originally intended through a board connector, make damn sure you don't pull too much amperage through it.