Ms. Pacman Cocktail monitor help needed.

MC35

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First off I want to mention that I am new to this, but have some electronics background. I picked up a Ms. Pacman Cocktail and 4 other machines for about what it cost to feed my dog for a month, but they all have serious problems.
I have attached some pictures of what Ms. Pacman is doing. I have read several forums and posts about common Ms. Pacman problems and have decided, I need some help. Here's what I have checked and replaced.
The 6 MHz bus at chips 2A - 2D is running at 6.137MHZ. I did replace 2B. All outputs from the previous mentioned seem to be running fine and riding on the 6 MHZ line.
After connecting the monitor to Golden Tee 3d and recieving similar symptoms I have decide this is a montior problem and not a board problem, although the board does still have some issues. (I am all ears if there are some other thoughts.) There is a sigifinicant humm out of the speaker and a high pitch squeal out of the monitor. (Per the pics, I am running this as Pacman for troubleshooting purposes.) All sounds work, and the coin mechs initiate a credit. I can play the game, just cant tell what is going on.
This appears to be a WG 4900 series monitor, but the Ms. Pacman book I have shows a 4600 series. I did install a 4900 cap kit from Bob Roberts and it did seem to help broaden some of the adjustments on the back of the monitor chasis. I am all ears and will post what ever pics needed to point me in the right direction. That is to say pictures of the game, not anything that I will regret in 10 years or so.
thanks,
MC
 

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Adjust or verify that your horizontal hold potentiometer is functioning properly. I recently had a very similar picture on a ms pac due to a malfunctioning horizontal hold pot...monitor worked fine after replacing it. It's worth checking anyway...
 
Looks like a "sync" problem to me......
Have you tried to adjust the sync pot?
Hard to tell from your pic, but that doesn't look like a 4600..... Snap a better shot of that monitor chassis....
A 4600 has 2 daughter boards on the chassis...
Also your PCB is a Pacman board hacked to play Ms Pac.......
 
Also, your PCB edge connector looks like it's got some pretty extensive damage. Ensure each of the connector pads are making proper contact with the harness. Again...just one more thing to check...
I'm sure someone more experienced with Pac/Ms Pac will have some better advice for you. Riptor is pretty knowledgeable on the subject :)
 
"Looks like a "sync" problem to me......
Have you tried to adjust the sync pot?
Hard to tell from your pic, but that doesn't look like a 4600..... Snap a better shot of that monitor chassis....
A 4600 has 2 daughter boards on the chassis...
Also your PCB is a Pacman board hacked to play Ms Pac....... "

Great responses from all. I am thinking sync as well, but I'm not sure where the sync pot is. I am fairly confident that this is a 4900 monitor, there are no daughter boards on the chasis as you and the schematics mentioned. If you have any suggestions on what to check and where to check I am completely open, I do have an o-scope.
As far as this being a hacked Pac man, I do have the ribbon cable and daughterboard for Ms. Pacman I just removed all of that and am running it as pac to simplify the troubleshooting of the monitor.
Thanks for all the help and I will post some better pics of the chasis.
 
"your PCB edge connector looks like it's got some pretty extensive damage"

There is some serious edge connector damage, I will be ordering the edge connector repair kit from Bob Roberts, until then I want to get the monitor issue figured out. Bob is getting to know me pretty good, and I would like to consilidate my shipping charges, instead of paying $7.00 a pop for a couple of IC's.
 
...I'm not sure where the sync pot is...

Sync pots == Hold Pots

I'd bet it's a horizontal hold issue, but you may also check your vert hold as well.
When adjusting your horizontal hold pot, does it do anything?
 
both hold pots seem to make some differences. When I adjust horz hold the image left to right do oscillate in a rapid fashion until it is adjusted right. it is harder to tell with Pac/Ms. Pac than it is with Golden tee. The pics below are what Golden Tee looks like when connected. This seemed to improve with the cap kit, but still looks like that. I could be way off by connecting Golden Tee, I'm not sure if the sync signals are even the same, but it is worth a try.
 

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If that is a 4900 I'm not overly familiar with that chassis.
Is there a pot on those that has a 50-60hz silk screened on it? If so that is the pot you want.....
Better pics of your monitor chassis would help......
 
no pot with 50/60 hz on it that I can tell. I can pull the chasis out of the cabinet if the above pics arent' clear enough.
 
google 4900 manual. I don't have one to look at for reference.
There HAS to be a pot on it that adjusts the sync.....
The H-hold, and V-hold won't adjust the sync.
 
Thank you. I did google it, and at first glance, it does appear that the manual on google is represented in the Ms. Pacman manual. Now that I have some more advice, I have a little more to go off of. I will be pulling out the o-scope tomorrow and giving it the ol college try.
Thanks again. I'll post what I find out.
 
O.k. I have determined that this is indeed aWG 4900 monitor. The problem is that the Pac/Ms Pac run off of a composite sync and the 4900 takes in - and + Horizontal and Vertical. I have tried running the Composite to just the Horizontal inputs and each one independently with no solution. Any advice on making this 4900 work would be great.
 
o.k. I am ready to pull my hair out, what's left anyways. I believe I need the horizontal width coil. According to Bob Roberts and my relentless search on the world wide web, they are unavailable. My concern is investing anymore time or money into a monitor that may not work for Ms. Pac anyways. I am very new to this and know little about vertical/horizontal monitors. I'm not even sure if a good working 4900 will work for this game. Can someone point me in the right direction. If it will work then I will continue attempting to repair this until I either fix it or my wife complains about my bald spot getting bigger.
Any help is greatly appreciated.
Thanks,
 
O.k. I finally got this up an running. I ended up using the monitor in my Pole position, which I also bought broken. The monitor is a Happ control 1915 , or something of the sort. After switching the connector on the monitor power supply, changing the - horizontal sync, and drilling a few holes in the metal chasis to make the board fit, it works!!! I can play it now, but it has a few RAM errors. I still haven't fixed the original monitor, but now that it is out of the cabinet, I can at least troubleshoot better. Thanks for the help.
 
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