Hello Everyone,

Picked up a Ms Pac in the spring. Really good condition cabinet wiring was mostly unmolested. The monitor was the only problem. It had a G07 could see the burn in but could not get any neck glow out of it. Finally figures out the heater element had an open in the tube. It took a couple months but found a compatible tube out of a TV. Got the Chassis working thanks to the G07 flow charts (voltage regulator and a couple bad caps). I got the yoke adjusted and the rings.
 It looked sharp on the work bench. When I put it back into the cabinet all the colors shifted. The midway logo went from blue and red to green and red and the screen was mostly green also lost all yellow. Tried to deguass the screen with no luck. I dont think its a board or chassis issue there is a couple spots where the color is normal. Also when I take the monitor out onto the bench it goes back to normal colors but if i put the monitor in the same position as in the cabinet the colors go all wonky again. Re-soldered all connector headers, made sure neck socket was tight, and manually deguassed the monitor with no effect. Any ideas?

Just pulling the the SBC board out of the socket can hurt them. Those boards pins are way thicker then chip legs and those old sockets only make contact with one side of the leg or pin. Newer dual wipe sockets make two points of contact with each pin or leg. Putting the SBC in backwards is a very common mistake. Check out lawnmowerman Pacman page. He has tons of screen shots of Pac errors to help trouble shoot. Mikes arcade also has a lot in his tech area.

If it has Sanyo 20ez you will need to run the video through the inverter board if it's still attached to chassis otherwise video colors will be inverted. Have seen a couple Nintendo cag to Janna adaptor snout there. Believe Mikes arcade has one.

Had a Makvision2425 doing this. Ended up being a bad capacitor c511 that is on the power up circuit.

If you have any picture at all then neck glow isn't you problem. You'll see neck glow on the neck not the yoke. The neck is the clear glass that the neck board sockets onto. It's really hard to see unless almost completely pitch black. As for the smearing colors I don't have a clue. You need to find out the type of monitor it is ( Pac are usually G07 or WG k4600) and start trouble shooting.

Sounds like a problem around the sync bus controller cpu or program EPROMs. Place to start anyways. Looks for solder blobs. Sync bus controller in backwards or the sockets for SBC or CPU or bent legs.

Had my first arcade party, have 3 cabinets and a scratch built mame cabinet. My Cousin and his wife stopped by with their 4 teenage kids, we fired up the BBQ and all my machines and I showed the kids how to coin up as i only had a few quarters. It was a blast at first everyone was drawn to Steel Gunner but that wore off fast and everyone was playing My SuperABC Pac-Man (they loved Piranha) and 1942 cocktail. I later swapped Pac-Man board out with Galaga and the high score battle was on. I really need some of John's High Score Stickies.

What a great night, cant wait to share my games again with friends and family.

Personaly I would stay away from MDF and use Good one side 3/4 plywood. It may not be the original material but it will survive a little water and your lungs will thank you for not using the MDF/Malamine.

I would guess a loose or corrupt eprom. They do tend to wiggle out of their sockets over time due to heating and cooling.

Go through them and push down on each one down. Saw a trick to use a stiff ruler to get ones in the middle board so you don't have to take boards apart.

If that doesn't work pull and re-seat each eprom in their sockets. if that doesn't work you may have bit rot on an eprom.

If you have a eprom programmer You can verify each eprom. If not see if you can find someone to burn you a new set and shotgun them.

FYI for WG  K4600 monitors.

http://arcadecontrols.com/BBBB/slanted.html

I think your right might be a problem on game board. Unplug the video input to monitor but leave power connected to see if the yellow line stays on the screen.

I think LovelyCoCoNuts is from Texas and may have Nintendo monitors but Redtent has a oddball size. Lot better chance of fixing it then finding a complete replacement. Good news is the Arcade community still has parts for those and documentation to troubleshoot and fix them as well.

Don't work on the game till you own it, owner may decide to not sell or jack up the price. You could inadvertently fix it short term pay extra then have it malfunction once you get it home. I would say deguass is disconnected or broken or a large magnetic source nearby. Screen is stretched  vertically(on the monitor, horizontal in real life) and is over-scanning which could cause the curl on the right bottom corner. Do like P-feif says degauss it and change the games orientation in the room.

Could try cycling the monitor a few times to get the attached deguass to work a bit, if you dont have a hand coil or wand you can try a power tool like a drill. Start a few feet away with the drill going full speed and work your way in making medium sized circles with drill till you get to an inch away then smaller circles in the affected area then slowly back away still making circular motions with drill. Power tool should be AC powered for better results.

I wouldn't touch the adjusting rings on the neck unless you have done everything else deguass, change cab orientation, wipe pots, adjust pots, check all conections on chassis. Nothing will ruin your day more them getting 30000 volts and crapping your pants, or being a little ruff on your first time out and cracking the neck.

WTG, good job.

Looks good. So jealous.