Can you identify this Galaxian PCB Modification?

VectorJunkie

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Can anyone point me to some information on what this modification is for? The ROMs on the far right and some of the others with the red wire connections have piggy backed chips on them. I bought this as a Ms. Pac board sight unseen, but can't find any pictures of the Pacman on Galaxian board mods to see if that might be it or not. It is obviously not a Ms. Pac board, but I want to figure out what it will actually play with this mod.

Thanks for any help!

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Well, you have a Pac-Man CT (at least your signature says you do), plug it in and see what happens. Galaxian boards can be tested in Pac cabs, you just wont have sound, and youll use up for fire.
 
Hmmm.... that's a good question. It looks similar to some mods I have seen, but the PCB that plugs into the Z80 socket is wrong. Plug it into your Pac-Man CT and let us know what you find.

Years ago on RGVAC someone posted about their efforts to modify the known Pac-Man on Galaxian ROMs. They modified the code, so the maze was closer to original and the colors looked great. Unfortunately, I haven't seen that thread since then and haven't had any luck find the ROMs (probably never got posted). I don't recall their being much to getting it working on Galaxian hardware (few mods).

Scott C.
 
It looks like it also has some power supply mods on it, so in don't want to plug it in without at least understanding those. If they are the DC mods, I count hook it up to a switcher to test it. Of course the board was sold as non-working so it may not do any good to test it. I will pull any non-soldered in roms ans dump them to see what I can see. I will post some more high-res shots when I get back home.

Thanks
 
Hard to see in your pic, but I don't see any mods to power, looks like just rom mods. I'm no expert on these though. I bet Riptor can help you with this one.
 
Hard to see in your pic, but I don't see any mods to power, looks like just rom mods. I'm no expert on these though. I bet Riptor can help you with this one.

You can clearly see the jumper wires on the diode and the power resistor....
Just snip those and put it in your Pac.
 
You can clearly see the jumper wires on the diode and the power resistor....
Just snip those and put it in your Pac.

Good eye. It does indeed have those jumpers. I was going to try and find full docs for that mod so I can undo it. If I undo it, I will have to cap the power supply as the caps are a lost cause. Should be able to get some high res pictures up in an hour or so. Someone did a bunch of work on this board for sure.

Thanks
 
Good eye. It does indeed have those jumpers. I was going to try and find full docs for that mod so I can undo it. If I undo it, I will have to cap the power supply as the caps are a lost cause. Should be able to get some high res pictures up in an hour or so. Someone did a bunch of work on this board for sure.

Thanks

From memory that looks like the exact same mods made on my board. I bought two in a deal for some other stuff and one of them had what looks to be the same mods.
 
Here is the link to the Flickr photo set.

http://www.flickr.com/photos/36768958@N05/sets/72157623071162872/

It looks like they are capping my maximum size of the images to 1024x768 which sucks. I could be doing something wrong in the upload. The close up shots still help though. Here are some of the highlights.

Some stacked ROMs...

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Processor board.

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Some more stacked chips.

4215251718_c40091215e_b.jpg


A bunch of add-on connections...

4214481411_44a9f8864a_b.jpg


Looks like this mod is increasing the capacity of the board for either a larger game or switching between multiple games.

Thanks...
 
Could be pac or mspac running on galaxian, I have no idea. I agree, clip the jumper and throw it in the pac cab and test it out. I have played pac on galax in mame but never actually seen it on real hardware.
 
It looks like Driving Force.

I found Driving Force when looking for board pics, but the daughter board on Driving Force is pretty big so I didn't think it could be that. It was pulled from a Ms. Pac cabinet, so maybe it is a Ms. Pac on Galaxian.

Do you have a picture of a more manual Driving Force mod? Here is the one I had found on KLOV.

Edit: Now that I look at it, it doesn't have the ROM sockets at the far right, so this image isn't based on Galaxian Hardware... I wish I could just dump the ROMs easy, but with them stacked and soldered it isn't going to happen. Next step is to see if I can run DC to the board and test it. If that doesn't go well, I will fix the power supply and throw it in my Pac.

Edit Again for Posterity: This image has the Driving Force mod for a Pac board and that is why it is so different than the Galaxian mod I posted.

1181242104157.jpg
 
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It looks like Driving Force.

Ok, I went ahead and pulled the ROMs on the board going across the center. The first one has "COPYRIGHT SEATONGROVE UK LTD" and "DRIVING FORCE" text in the ROM.

Not sure how this UK company fits into the information on Klov. Anyway, does anyone know if Driving Force is any good? I'm probably more inclined to restore this back to a Galaxian and maybe putting one of those 8-in-1 multis on it if they are still available.

Thanks Matt!

Edit: Of course the ROMs were labeled DF1 to DF4. :D
 
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I have a Driving Force on Galaxian hardware. It's not a terribly exciting game.... You should try it just for fun anyway.
When converting it back you'll have to re-enable the background starfield (there is more than one way to disable it, but they usually clip pin 15 of 2B).
 
I have a Driving Force on Galaxian hardware. It's not a terribly exciting game.... You should try it just for fun anyway.
When converting it back you'll have to re-enable the background starfield (there is more than one way to disable it, but they usually clip pin 15 of 2B).

I replaced those nasty caps, and removed the wire jumpers. I get some graphics patterns like it is going through a self test or something, but it ends up just being garbage. I'm going to try and find a pac transformer block and harness to setup a test rig on my bench so I can dig into this and a couple pac boards. Klov actually had a nice writeup on this mod (below). I checked B2 and pin 1 is cut. I pulled the datasheet on the chip and it inverts then ANDs pin 1 and pin 15. So I think cutting pin 1 would have the exact same effect as cutting pin 15. Thanks for the heads up, I would have been scratching my head to find a star field problem if it goes back to Galaxian.

Hopefully it isn't a problem with the hacked components so I can try to fix it and play it as a Driving Force. If it is screwed up in stacked chips, I will probably just pull that stuff off. I don't know that I am up to the challenge of trying to repair those stacks. :)

Thanks again,

-VJ

This is a conversion on a Galaxian board that includes a new ROM daughtercard (labelled "=LIGHTNIN' VIDEO=, MEM B'd") that has four 2532 EPROMs on it, a pair of piggybacked 2532's for each of the graphics ROM sockets at 1H(J) and 1K(L), a pair of piggybacked 82S123's for the color PROM socket at 6L, and an epoxy pack (labelled "EX-PAK, CVS technology, copyright 1984") that plugs into the Z-80 socket. A 74LS175 is placed on top of the chip at 6R. Several jumper wires along with some lifted chip legs (or cut traces) are required to complete the conversion. The Galaxian background stars are disabled by clipping pin 15 of the chip at 2B.
 
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I wrote that KLOV entry (or at least the tech part that you quoted). :) I took that pic of the marquee too.... that was a long time ago and I didn't have a very good camera back then. I think I still have the CP overlay too.
 
Since this thing didn't work in my Pac and it had a DC power supply mod, I assumed that the original power supply might be toast. Those nasty caps were obviously a problem, but those were already replaced. Anyways, I finally had some more time to mess with this on my bench. I just bypassed the power supply and hooked the board up to an LCD.

4227754958_6222fd306b_o.jpg


I can tell it is running through the attract mode, so that is progress. At the following link is a very short video of the board running.

http://www.flickr.com/photos/36768958@N05/4226978857/

The ROM sockets that the four ROM daughterboard is in look like they suck. I need to read through some Galaxian information to see what some common board problems are. I'm just guessing those sockets are suspect just like a pac board with the little riser boards. Anyway, wish me luck. I hope to be a Driving Force sometime after my Pac harness and transformers get here.
 
Looks like it's running code fine, but the sprites are wrong. I'd first look into the stacked graphics ROMs at 1H and 1K and the added circuitry for selecting them.
 
Looks like it's running code fine, but the sprites are wrong. I'd first look into the stacked graphics ROMs at 1H and 1K and the added circuitry for selecting them.

Thanks for the pointer... I was afraid you would say that. :) Too bad there isn't a schematic of the Galaxian based version. There are three other chips with legs cut and I think they are all part of the modification. At least one of them manipulates the interface to the data bus. I suspect that it is driving the interface from the CPU daughter board instead.

Anyway, I decided to keep it as a Driving Force for sure. Galaxian isn't that hard to find so if I want, I can find another one. If I get stuck I will create a repair thread and link to it for anyone interested.

Thanks,

-VJ
 
VJ,

I have a stack of Galaxian boards here to fix and mod for multi-games.

RJ
 
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