What causes this Pacman screen?

GoneMad

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Solved..What causes this Pacman screen?

I just hooked up one of my PM PCB's. I am getting the same screen on two boards when I power on.It is the third picture down on the right side on the following link.
http://www.arcadegameover.com/pactrouble.html
I have tried what it says for solutions but nothing. What I wasn't quite sure of was when it says E1,E2 short p2 to 1,3,4,5,6,8. Does it mean to short pin2 from E1 and E2 at the same time to all of the following pins or to any of?
Or could it be that something is wired up wrong?
 
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I think he means, on E1 or E2 or both, pin 2 is shorted to pin 1, 3, 4, 5, 6, or 8. As in, that's a problem that would cause this, not something you should do.

Pull the current board out of the machine and look for any metal pieces that may be touching the board when you put it in. Seems really suspicious that both boards would do the same thing.

Also give the cabinet's fuse block a once over. Check fuses with DMM, clean up the fuses and contacts, make sure they're making a good connection.
 
Yea, it's not really clear on that site. It's says problems and solutions, so assuming the top portion of the box was problem and the bottom was solution. I get the same screen with the board in or out of the cab. My harness is long enough i can lay the board on a piece of cardboard for easier swapping. I have checked the voltages going to the board and they seem fine. I am using the DC method as shown here.
http://www.mikesarcade.com/cgi-bin/spies.cgi?action=url&type=pinout&page=Pac.html
I think he means, on E1 or E2 or both, pin 2 is shorted to pin 1, 3, 4, 5, 6, or 8. As in, that's a problem that would cause this, not something you should do.

Pull the current board out of the machine and look for any metal pieces that may be touching the board when you put it in. Seems really suspicious that both boards would do the same thing.

Also give the cabinet's fuse block a once over. Check fuses with DMM, clean up the fuses and contacts, make sure they're making a good connection.
 
OK. I just went and took another good look at these boards. Something is not quite right. These were geared up for Ms. Pacman but the daughter boards were not attached. Still, something's missing. THE Z80!! I checked the first daughter board and none there, so I went and got the 2nd one and there one was. I put this back on the board and booted up with fingers crossed. Dammit, still the same screen. But just for shits and giggles, I hit the Player 1 button (set on free play) and it started playing blind. I moved the joystick around, ate a few dots and shut it off again. I checked and made sure the sync was plugged into the chassis and it was. What I'm thinking is the 5E and 5F are graphic, right? And they have to be put back to Pacman? Can someone set me straight on this, maybe? Thanks.
 
I just swapped these out from the other board and the same. So, through process of elimination, this is a monitor problem, this monitor worked wjen i juzt removed the commando pcb. Or shpuld i start a mew thread in the monitor section?
 
I just went and tried my other pac board. It does not work, I can hear it try boot but it still gives the same screen with either board. I have checked the wire to the sync. They seem to be alright. I powered the board with the sync connector disconnected. The only difference was the small lines got thicker. Does anyone have a G07 hooked up to their pac they can take a picture of I can compare with? Thanks



Edit. I have it hooked up exactly as in this pic.
 

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Play with your horizontal frequency control. Maybe it's syncing up to a multiple of the correct frequency.

It shouldn't be off too much though, since you said it was working with a Commando board.
Tap around on your two daughterboards. Make sure they're seated well.
 
Yeah, I agree with kstillin. I've got some bootleg DK Jr boards that do that when I hook them up to my G07. It works fine with other boards, but when I hook them up, I get video similar to this, and I always have to tweak the horizontal freq pot.
 
Play with your horizontal frequency control. Maybe it's syncing up to a multiple of the correct frequency.

It shouldn't be off too much though, since you said it was working with a Commando board.
Tap around on your two daughterboards. Make sure they're seated well.
That seemed to work. But as I adjust the pot, there is only one spot where it tunes in the screen. I have tried the other pots and have the screen pretty good, but the bottom line of the maze is at the very bottom of the screen. You can't see the extra men you have left. Could the the H freq pot be toast? I do have an extra WG4903 that I could try slip in there.
 
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