A few general questions regarding Pac/Ms. Pac games?

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A few general questions regarding Pac/Ms. Pac games?

What is the purpose of the Filter Board in pac-based games? I have one in my cab and cannot tell the difference between running the game with or without this board. My manual states that it is "optional" and a "service option". What does this mean?

Also, a question regarding EPROMs/PROMs on various pac-based boards. I know that all pac-based boards use the same mainboard with different EPROMs/PROMs or daughter boards on them. Are the two "piggyback" boards generic and interchangeable on all machines or do they differ? I recently acquired a non-working Glob board and am trying to fix it. Can I take the piggyback boards from one mainboard and use it on another with another?

Finally, outside of the EPROMs/PROMs that are changed out with various pac variants, are there any other differences between the other components on the main boards?

I am fairly new to pac games, so if this information is already out there, I apologize. Links would be appreciated. I have done a lot of surfing, but can't seem to find the info that I am looking for. I check BR's FAQ section and other common sites.

Thanks,
Dane
 
Well as far as the EM filter boards. They help prevent EM interference from other electronics. I'm sure back in the early days of electronics there was lot's of interference from other electrical sources. Today not so much. So you can typically remove it without adverse affects, and plug the edge connector directly to the game board.

Other uses for those boards would include keeping cross talk from different signals down, but since we are talking 1980's the spacing of components, wires etc was much greater than today, and speeds were much slower than today's standards.

The rest I'll have to defer to someone who's got more XP on Pac boards.
 
The original purpose was two-fold:

#1 was static electricity causing the game to reset/reboot when you touched the chrome coin entry with your quarter. Game would reset and you'd lose your quarter. That's why so many Pac/Ms. Pacs had bashed-in coin doors.

#2 was that later in the production run the FCC was demanding the game reduce radio and tv interference or else the FCC would not approve the machine for sale in the USA. Thus Midway quickly came up with this plug-in board.

IMO, take this board and throw it in the trash. It's been nothing but trouble. The game will run fine without it.
 
As always, thanks for the info Ken (and Talon of course). I will keep the board out. Another question that I have it regarding the 4 fuses coming out of the power supply leading to the various areas of the cab. I purchased replacements after blowing several via a monitor discharge and like an idiot did not note which came from which position. 2 are 5A 250V, one is a 1A 250V and the fourth is a 5A 250V slow burn fuse. Can anyone tell me which goes in which position?
 
The two daughtercards are the same for pac and mspac. Some early build pac boards had custom chips instead of the daughter cards.
There were two different aux cards. One was mspac and the other was pac plus. The mspac is a plain pcb, the pac plus was sealed with epoxy potting in a plexi enclosure. Pac plus and ms pac both run off the standard pac pcb. To run pac plus required the aux board, 6 roms and two proms changed.
To run ms pac only required aux card and two roms at row 5. Pac and mspac both use the same proms.
There's several pages on the net with this info but I dont have the links handy since I just did a fresh install on a new HD on this pc. I gotta get my links imported among a ton of other things.
Go to the klov list (www.klov.com) and bring up the page for pacman. At the bottom of the page there's a link for the manual. Download the manual and your fuse info is right in there.
 
Sweet, thanks for the info and suggestions on links Riptor. I figured this info was out there, but anytime I did a search with pac-man/ms pac-man, most of what comes up is garbage.
 
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