Bally 5000 Plus, whats the "-12" volts for?

[rvcullen]

Hey guys! Wonder if anyone might be able to help me?
I bought a  5000 Plus for $100 from someone and it was in decent shape, aside from a little surface rust, but i am still working on reviving it. Maybe someone can assist me in figuring out a power supply question?
Originally the unit was dead except for the backlighting, supply was dead. I got it running after finding an open resistor but the game would act all crazy and never fully reset (lots of random clicks and then the jackpot bell would go off). Voltages all were there except it had no "-12" so I decided to buy an aftermarket power supply (MeanWell RQ-85D). the only lead I left hanging was from Pin 1 on the old supply which looks to be a POWER FAIL lead.
So now the new unit is in with all the voltages tied in but now the CPU will not exit reset (both LED's on MPU stay on all of the time). I recehecked all volts and all good. i decided to try disconnecting that "-12" volts and lo and behold the game turns on ok and, I THINK, seems to be working. I now get a 52 and a couple of JP messages and hear the coin meters ticking away. Not sure on that but I will probably clear it now.


Anyone know for sure what the -12 volts do and if I need it, and/or why it would not reset with it tied in??


Thanks guys!

[rokgpsman]

A drawing I saw shows the -12 volts going from the power supply to the Backplane board connector J13 pin 10 and then comes out at Backplane connector J15 pin 2. Connector J15 is where the wiring cable for the "RX/TX" comm board is connected. This may be a board that's used to connect the machine to the casino computer network, or maybe something else, I'm not familiar enough to know. Do these connectors match-up with what you see on your Backplane board, this may not be the right drawing for your machine. Bally may have used different backplanes for different game configurations (slot, blackjack, poker, keno).

Anyway, if you have a Tx/Rx board the -12vdc is probably used by it for the comm databus circuit, it is common to power a databus with +12 and -12 voltages. Other than this I didn't see any place the -12 volts was used on the drawing (unless your machine is a Keno - see below). If the Tx/Rx board is only for connecting the machine to the casino server then it may not be important for home use, unless the machine mpu board checks the Tx/Rx board on powerup as part of a selftest or something.

The machines setup for Keno also use the -12 volts going to an additional board called the "UGDM" board.

Maybe you can examine the old original power supply and see if the -12 volt wire was even connected internally and meant to provide -12 volts to the machine. If not then your machine probably doesn't need the -12 volts.

Can you verify that your machine has a Tx/Rx board? Also, does your machine have mechanical spinning wheels, or a video screen display, if video display then what kind of game? A few photos of a machine always help us to know what you have, there are many different models out there and we can waste time and effort guessing or giving suggestions that end up not even applying.

You may already know this, but just in case, on some (or all) of the Bally 5000 models I think they use a Keypad for diagnostic and troubleshooting reasons.


PS> Welcome to NLG!   

[rvcullen]

Thanks so much for all of your information! I will definitely get pics up, just have to clear her up a bit first too,lol. I am in the process of making my own keypad as another thread had listed a mod for a 4x4 matrix keypad on these games. Next to impossible at this point to get an original keypad. I just didn't know if i might be missing that -12 and ever really need it but it looks correct to me on your comments of pins, etc.
Still not really sure why it would not reset with that -12 on the pin, but the plug on the backplane actually marked all of the other voltages except this -12 as well, so maybe it is not for this particular model or game I have.
BTW, the unit I have is a "Solid Gold" 3-Reel game, no video or display screens on it except the usual coin/win LED displays. I did find it cool that under the glued "5000 Plus" plaque on the lower door there is still an old card reader and small LED matrix display, obviously for an old player tracking system. Would be neat to rig that display up to scroll my name or something,lol!!


Thanks again. I'll try and update with some pics soon! Just got my ram clears in the mail today too.

[rokgpsman]

Sounds like you have a good plan, keep us posted on it. I take it your machine doesn't have that "Rx/Tx" board that would use the -12 volts, and there is no cable connected to the backplane connector J15?

There's probably some guys here that may be able to help activate that old player tracking panel but the electronic box that connected to it was probably removed long ago by the casino, they often keep that kind of equipment when they get rid of a machine. The old player panel may have been left in place because there'd otherwise be a hole there, or maybe it helps to hold the nearby glass in place, and someone covered it for appearance reasons since it wasn't going to be working anymore.

The machine doesn't have to look perfect for photos, we've all seen old machines that had a rough life after casino service, so no points off for that. Some of the battle scars add a little personality. 

[rvcullen]

Thanks for your help! Yes, no comm board to speak of. I think I got a bum set of clear chips, so working on that issue too.