I am building a Pinstar Gamatron now. Starting from just a playfield and whatever I have on hand.

I have a Stern MPU and SB-300 sound board. I am aware that the game uses Flight 2000 roms so I am just running those in the Stern MPU, correct?

So, will the SB-300 sound board work in the game without modification?

Also, if I have an Eight Ball wiring harness [6 digit wiring harness and displays], the game running will essentially be flight 2000. So, should I do something special to get the game to run with only 6 digits?
Or, should I use 7 digit displays [adding a wire to the harness for the 7th digit] with the Stern MPU and SB-300 sound board and run it exactly like Flight 2000?

FYI, I do not have a Gamatron PCB [that lives on the left side of the cabinet] but I have read elsewhere I don't really need one to build the game if set up like Flight2K.

I know that but, will Flight 2K run with six digit wiring+displays?

Ok, I read those instructions for 6 digit displays and it seems fairly straightforward, moving pins around and adding one... thank you.

Sound wiring question: looking over the SB-300 schematics... what all wires do I need to connect here @ bottom of the PCB?

@J2: Just these two? [pin 6] 11.9VDC and [pin 3] GND ?

@J3: pin 8 [speaker -] and pin 9 [speaker +]

and [pin 1] and [pin 3] goes to the volume pot. ? @ 25K ohm, 5 watt?

Could someone check there are only actually six wires total at the bottom of their SB-300 PCB connectors for J2+J3? I assume if I check Nine Ball the connectors @ J2 and J3 would be the same as Gamatron?

I'm also assuming Gamatron has no knocker because it says to disconnect it in the kit instructions?

Screen Shot 2023-04-24 at 9.48.34 AM (resized).png

And some guys just have a full set of working 6 digit displays and want to use what they already have in hand.

Need some Gamatron expert advice. Mike? I have some connectors from the playfield and I don’t know what to do with them.

The connector in the last two
Pics. No idea where it goes? Is it for the lower left connector on the lamp driver board?

Next, the lower cabinet connector in first picture. Do I just combine all the wires from both connectors to make one connector? Just plug in the Gamatron one? What do the three wires farthest to the right do? (I’m using a lost world cabinet harness.). I am confused on what steps in the conversion instructions I follow (if any) and what ones I ignore since I’m not using the Gamatron pcb from the kit.

So far, all I have done to modify the harness is the instructions directly under “For games with 6 digit displays.”

07DD4C78-5D4F-427F-B991-B046139BB1A2 (resized).jpeg52D253AB-D342-400B-9F9C-397DA4DD2512 (resized).jpeg80BB7FFE-22C3-4A4D-8F44-8E2DA92EE138 (resized).jpeg

I thought there was only one unused connector, the POWER one for either -18 OR (Molex plug style) -54 rectifier boards.

There are instructions deep in the manual on moving pins in the (trans driver board) connector in my first pic. Not sure if I should do those steps or not.

Ok, I think I figured it out. I need to splice these 4 wires in this picture to the old connector and you do not plug in the old connector, just the new one. I believe these are for the flipper buttons…

That other plug that goes to the lower left on the lamp board has four wires you are supposed to splice in that are for tilt, game over, extra ball, and hstd. I only really care about the tilt bulb in the head but I am skipping that for now.

Here’s what I did:

FBAB60D8-5F6A-44B1-AC2C-C8C3F56B1D25 (resized).jpeg

An update. I still need to order cables for the sound board. I think that’s the only thing I still need besides waiting on Seigecraft LED boArds.

A0151E91-0989-4156-825E-6F0AABE59E9B (resized).jpeg

I discovered that "classic Bally" potentiometers are NOT the same as the ones that Stern used in their classic games.

If your classic Stern [or Gamatron running a SB-300] is missing it's pot. to adjust the sounds...

buy one of these. https://www.parts-express.com/25K-Ohm-Potentiometer-023-540?quantity=1

I bought a couple and including shipping, it was under $10.

I installed this 25K ohm POT and I can confirm that it works great for the Stern SB-300 sound board.

I just made my own sound cables using some old PC ribbon cables with the last two pins bent out and now the Flight2K sounds on my Gamatron are working!
37C239D0-562F-40A8-BAAC-720B2F9E0F86 (resized).jpeg9DF81658-F2B2-4BA9-9F8F-DE08D1D41860 (resized).jpeg

I ran into some issues with the game booting consistently. Fairly odd behavior...

When powered on for the 2nd,3rd,4th time ect. after putting in the desired "option" settings and then also after sitting cold overnight, the game would not boot the next day until I removed the batteries.

If I removed them and booted the game and set the "option" settings up again, the game would then consistently boot 10,15,20 times that day BUT after it sat overnight, it would not NEVER boot again the next day.

But, once I removed the batteries, all is well and the game has booted over 50 times with no issues now. Only annoying issues with this is adding credits but it holds 40 credits so, I'm just leaving batteries out.

I tried a different known good MPU, power supply, driver board, transformer, and different holders, different batteries (even a coin one) and am convinced that there is no solution to this odd problem. And before someone asks , yes I did use a diode in the battery holder.

I even had the same thing happen when on the test banch using an ATX power supply! So that eliminated every cause but for multiple tested MPUs... oh well.

Maybe NVRAM would "resolve" this but, I don't really care enough to use NVRAM and I fear that it would exhibit the same behavior if I ordered and installed it.

Just posting here to let other potential owners know of this odd issue. Seems to be MPU/settings/Flight 2K code related. I found some other chatter about it in the F2K owners thread so I am just assuming that I am seeing the same symptoms here, since Gamatron uses the same code.

But I'm not using a PSM board, I don't have one. I am using a Stern MPU with F2K roms and a stock Stern sb-300 sound board. I took a great deal of time and care documenting my process on paper so that someone else could also do this if all they had was a Gamatron playfield.

I do need one. Would be interested if it’s in good condition but “expensive” ? Not sure what that means. If it’s more expensive than a typical backglass 200-300 plus shipping then I would not be interested.

Me three. LOL, I see what you did there.

Sounds like it could possibly be glued in there with adhesive... Mine just popped right off. If you do destroy it, I do believe the BASE where it mounts is a standard size plastic body (and standard red pop cap) that you can simply buy from Marco and then use standard screws if you do go that route.

Maybe someone else can confirm that the base is the "standard size" part. The odd part of the assembly is the plastic ring and the underside bits.

If you come to a point where you can’t get the Pinstsr board to work, you don’t actually need it. You can just run Flight 2K on a Stern (or weebly) board without it.

The only thing that board does is allow you to run a Stern game on a Bally MPU.

No, because you have to do those for the playfield and insert lamps even if you run a Stern MPU… they have nothing to do with the game booting and running the roms/code on either a Bally or a Stern MPU. They made that kit to be spliced and installed into a Bally game, just like you have.

You would also need a Stern sound board but, Weebly has them for $99.

I always prefer to try and run the original Pinstar board but, if you reach a point where you can’t I was just offering another option to get the game working. Besides, that board is hard to diagnose and repair because this game the only one that ever used it.

Not certain what you mean. You only have to change the display wiring if you use 6 digit displays. Instructions to do so are in the “conversion kit” manual. If you use 7 digits, you don’t need to change the harness, other than potentially adding one wire, if your donor Bally game was a 6 digit. So, Its likely set up the proper way in your game for whatever displays you have there.

I actually just made some up with standard paper and a color laser printer. They look ok.

That's awesome. Thanks for the update.

Likely mechanical. BUT, can you disconnect one wire on each coil to confirm that they are actually BOTH firing individually? Once you confirm that, it's down to mechanical spring tension being too high, or dirt, coil sleves, rust, crud causing it.

It’s because it’s impossible to use switch diagnostics with 6 digit displays. The “ones digit” is not shown in this case. Best you can get is a “some switch is registering” confirmation.

I would not worry about those boards… there is no such thing as “Gamatron sounds”. Same sounds as Flight 2K.

There is no difference. The added GAMATRON speech call you mentioned is an aftermarket mod.

You should be able to use a standard Weebly sound board [+speech board] to play F2K speech calls. Gamatron back in 1985 had no speech.

To make sure there is no misunderstanding... The ONLY reason Pinstar made their large green "add-on board" and included it in their kit, was to play Stern Flight 2K game code on a Bally -35 MPU. So, you don't need it. It was simply a hack.

Yes, but where would you get the playfield? The kits came as a fully assembled PF. No reason there should ever really be a blank PF kicking around.

Maybe I misunderstand you? Gamatron IS VERY CLOSE to a Flight 2K. Both mechanically and electronically. They just moved a couple targets/lamps around the playfield and changed the letters and the art. It runs the same game code.