WTB: Jamma Switch Board for at least 2 boards

[Belike]

You can have it for the shipping price.

woha.. thanks mate!

pm for the rest?

Ok.

[Belike]

Made some tests meanwhile, seems like only 1 connector has the power at a time.
I have 2 of these adapters, one wokrs only with the bigger connector (with those parts) and the other with the simple jamma edge connector.Both were working with that  switching button before I burned up those ugly Challenger cabinets, so I'm sure they give only power for 1 pcb at a time.

[level42]

Did you measure Béla ?

I based my judgement on those pictures. the Big wide tracks on the edges are the power supply lines and they run from one side to the other without anything in between them that can switch them. The wires to the other connector also look like they are soldered directly to these tracks so that's why I thought there is no power switching going on....

Not saying you are wrong just explaining why I thought this way

[bencao74]

I was asking myself why those transistors are used. Probably they`re switching the power lines. Otherwise I`m getting out of ideas what the job of these ones are.

The 74ls74 must contain some logic triggering the transistors. So if there is no 4066 similar analogue that switches the two pcb output rgbs lines will fire at the same time. Means that there must a kind of power select for the both PCB edges.

[Belike]

Did you measure Béla ?

I based my judgement on those pictures. the Big wide tracks on the edges are the power supply lines and they run from one side to the other without anything in between them that can switch them. The wires to the other connector also look like they are soldered directly to these tracks so that's why I thought there is no power switching going on....

Not saying you are wrong just explaining why I thought this way

Seems like you are right, I measured both edge connectors, the +5,-5,+12 volts are all there, but only one works from the 2 at a time.

[Belike]

I'm really curious by now how is it works, so I made some more pics:
The loose wire connects to this point on one side

It comes out on the other side here and connected to those blue somethings.

The cp from outside, it is the white button between 1 and 2 player start

One wire comes here from that switch, the other is loose

[bencao74]

4th pic wire is gnd.

1st and 2nd. The wire is goes into the diode and then to the transistor, nor?

[Belike]

4th pic wire is gnd.

1st and 2nd. The wire is goes into the diode and then to the transistor, nor?

Yeah it goes there and both sides of that diode is connected to those transistors.

[bencao74]

perhaps the GND lines are switched.

[cebulba]

I do have a similiar T-Adapter for Jamma. Pics later the day.

[Luigi]

I have one, too.

IMHO it's better to have both PCBs powered at the same time instead of booting them every time you switch between them. You don#t have to wait each time you switch and I think it's better for the electronic parts to be powered on once on an evening...or am I wrong?

[bencao74]

good point. Especially for setups with pcb like choplifter or multigame pcb, which need much boot up time.

I have two quadros in my gameroom, Luigi, I think you have even more. Sometimes I think it`s not very comfortable to power 8 Arcade PSU each with 150W at same time. But this is another story...

[Luigi]

good point. Especially for setups with pcb like choplifter or multigame pcb, which need much boot up time.

I have two quadros in my gameroom, Luigi, I think you have even more. Sometimes I think it`s not very comfortable to power 8 Arcade PSU each with 150W at same time. But this is another story...

Well, I think it's comfortable cause you don't have to care if your only PSU is able to feed the four PCBs

Of course, you have to pay the current for having all four PSUs and PCBs running at the same time.

[level42]

I wasnt saying it was neccesarely a bad thing that the PCBs were both powered all the time, I only mentioned it because you do have to make sure the power supply you use can provide enough power for both boards.

Oh and gentlemen, I see only 1 transistor and that is the TIP. The light-blue colored "boxes" are relais. They switch signals from one board to the other when you switch between games. Each provides two switching contacts so there are max. 8 signals switched by them on that PCB.

Again, the tracks run straight from the input to the output connector (and the wires running to the 2nd connector). If the power lines would be switched, those tracks would have to go to a relay contact.

[Belike]

I have a few more of these, if anybody wants to make some experiments or write a book from these, just let me know.