Jamma 6-In-1 Switcher Mod Tutorial

zenomorp

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Hey guys. I thought I'd help anyone who has or is getting one of these 6-in-1 Jamma switchers and needs to do the -5vdc and/or service menu modifications. Here are some pics and videos on how to do everything. Any questions, feel free to ask...(sorry for the bad pics, but that's as clear as I can get. My camera doesn't do so well close up..)

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nice.

there should be a setting on the camera for close up photos.
on mine its a picture of a flower.

Depends on the camera, most modern point & shoots have a macro mode (usually a flower icon), but some of the new ones and a lot of older cameras don't. I really need a macro lens for my DSLR.

Thanks for the link to the thread, I was trying to remember who the hell it was that had posted their multi-mk setup. I'm doing a multi cabinet with a few SFIICE boots and a couple other games and I've got the jammaboards 6-1. I know that you have to run diodes in line with the wires coming off each kick harness then connect the individual ones together, which diode was it that was needed and how did you get them all connected? One big crimp-tube, those screw cap connector things, something else?
 
That is pretty sweet. I like how you have it mounted in the cab.

For me if Only i could find some replacement relay's. Slot 5 and 6 do not work and through some trouble shooting and a meter I have found that the relays were blown/fried. I've asked multiple times on Jammaboards.com(place where I bought it) for some replacment relays, however they never get back to me. Any ideas?

Thanks!



;
 
Mouser, Newark, Allied Electronics.....all of them should have the realys...make a phone call and give em the numbers off the old relay...

Josh
 
You do realize that with that hack the -5V isn't switched, so you're powering the -5V of all the boards all the time, which your power supply probably won't like, and your boards may not like it either...
 
you also need some way to secure the far end of each board - there would be a lot of flex in those boards and at the jamma card edge/socket as a result of small vibrations/bumps even during game play.

a force applied on the side of the cab parallel with the direction of the game boards would introduce movement in the sockets and possible vertical movement as well. a bump on the front would exert force on the boards toward the front & back of the cab as there is a large degree of freedom without the far end secured. a bit like a flag in the breeze.

you may end up with pcb material and switcher socket fatigue failures from movement over time. gotta protect those boards and sockets from physical wear and tear! if the assembly was more rigid, with a rear frame or top/bottom frame to support the back edge of the boards, would be better long term!

all said and done, a nice setup :)
 
You do realize that with that hack the -5V isn't switched, so you're powering the -5V of all the boards all the time, which your power supply probably won't like, and your boards may not like it either...

I used relays on mine to cut the -5v to the sockets when not in use.:)
 
I know this post is ancient, but I was looking into this for my 6 way switcher I'm installing my my SFII cab. I noticed something weird though... what's with the diodes on the GND to 27/28 and e/f? Shouldn't they be the same GND as A/B and 1/2, and simply connected between the boards?

I also noticed that they have traces and diodes installed for the unused pins 25/26/c/d... that's kinda convenient. I'll probably wire my boards to use these for buttons 4/5, so the boards will be more easily swappable without dealing with kick harnesses. For button 6, maybe I'll go to 11/M.

Also, has anyone run into problems from running -5V to the board all the time? That seems like a bad idea to me, but I guess if everyone does it, and hasn't had any problems from it... maybe I shouldn't worry about it. Using a relay seems like a better idea to me though.

DogP
 
I know this post is ancient, but I was looking into this for my 6 way switcher I'm installing my my SFII cab. I noticed something weird though... what's with the diodes on the GND to 27/28 and e/f? Shouldn't they be the same GND as A/B and 1/2, and simply connected between the boards?

I also noticed that they have traces and diodes installed for the unused pins 25/26/c/d... that's kinda convenient. I'll probably wire my boards to use these for buttons 4/5, so the boards will be more easily swappable without dealing with kick harnesses. For button 6, maybe I'll go to 11/M.

Also, has anyone run into problems from running -5V to the board all the time? That seems like a bad idea to me, but I guess if everyone does it, and hasn't had any problems from it... maybe I shouldn't worry about it. Using a relay seems like a better idea to me though.

DogP

The -5v all the time concerned me too, but our
Is -5v really anything with out the positive voltages connected? Or is ground sufficient?

To be honest while I understand the premise of -5v I don't know all the details.
 
considering the -5V only really works in conjunction with the sound hardware, I don't actually think it would do harm to any other components on the boards.

in the cases of MK1 and MK2 in particular, I think the -5V just piggybacks from the JAMMA edge straight to the header on the sound board. I really wish I knew exactly what the -5V was for though with those.. I just know about the horrifying sound it makes if it's not present lol
 
Negative voltage is just like positive voltage, except reverse polarity. Imagine putting a AA battery in backwards... that'd give negative voltage. Let's call terminal 1 the GND terminal, and terminal 2 where the positive voltage should be. Normally, terminal 1 is 0V, terminal 2 is 1.5V... when you connect a battery backwards, you could say terminal 1 is 1.5V and terminal 2 is 0V, except that we said terminal 1 is GND, which is what all voltages are referenced to. So, relative to GND, terminal 1 0V and terminal 2 -1.5V.

Anyway, negative voltage is completely independent of positive voltage, and things can still be powered, and current can still flow whether or not positive voltages are present or not. I haven't looked at how negative voltages are used on these boards, but it's common to use them as the negative voltage for amplifiers. That way they can amplify bipolar signals... if you used GND as the negative rail, any time the input signal went negative, it'd clip to GND (so you'd only get half the signal). I don't think there's any problem connecting a negative voltage to an amplifier if there's no input signal (since the rest of the board isn't running).

Some of the old boards used it as one of the voltages for RAMs and ROMs (they took +5, +12, and -5), though I don't think anything JAMMA would be using that. I've read that those could be damaged by running extended periods with a voltage missing.

DogP
 
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