Build Your Own Arcade Controls Forum
Main => Monitor/Video Forum => Topic started by: claremont on September 21, 2012, 09:41:32 pm
-
I have a freshly rebuilt Ms Pac board, and am hooking it up to a WG 19K4901 montior. Please see the YouTube video for explanation of what is going on:
http://youtu.be/bl7_-GLgeTI (http://youtu.be/bl7_-GLgeTI)
-
i would try this forum below to increase chances of resolving:
http://www.ukvac.com/forum/tech-maintenance-repairs_forum2.html (http://www.ukvac.com/forum/tech-maintenance-repairs_forum2.html)
-
it looks like its going through the regular boot screen, but with no video sync and it keeps restarting and trying to boot.
Did someone rebuild the board for you? is there a warrenty?
I assume the caps on the game board were replaced. Are the polarities correct?
make sure all chips are seated fully and correct direction and check the sync bus controller card.
also check here:
http://arcarc.xmission.com/Web%20Archives/Pac%20Man/Pacman%20Troubleshooting%20Files%20(103%20Images)/pactrouble1.htm (http://arcarc.xmission.com/Web%20Archives/Pac%20Man/Pacman%20Troubleshooting%20Files%20(103%20Images)/pactrouble1.htm)
and check mikes arcade repair logs
-
This AM I switched the pac board with another board that is working fine in my cocktail cabinet. Sure enough it does the same thing! So, that suggests that I have something wrong with my install. But, even if I have the video wires between the harness and the monitor out of whack, would that cause the board to go into a constant reboot? I would have thought that the video would be messed up but it would still eventually rest on the main screen, not constantly reboot.
-
Yeah, not having sync hooked right or something like wouldn't cause the boardf to keep rebooting.
What's your power supply voltage?
Just a thought, maybe you have the voltage too low and your sync is hooked up wrong.
Many times a board will constantly reboot if th 5 volts is low.
How is your cabinet wired, Jamma ( with adaptor for ms pac)?
What's the other board you tried?
-
I have a switching power supply. I have adjusted the voltage between 5 and 6 volts with no difference.
It is a new Jamma harness with a an adapter to the original Pac Board.
The switching power supply has a broken voltage adjustment knob. I can adjust it, put it is a real pain in the butt.
I think I am going to remove the video wiring, clean up the wiring connections, and give it a try again. Now that I think of it, the sync wires might be loose or poorly connected at the header end of the harness.
-
I only have negative horizontal sync hooked up at the monitor. The other syncs are not used. Pac is a negative horizontal sync game, but I dont know if that rule changes when I am going through the Jamma adapter. I cant imagine it would, but I am just about out of options at this point.
On Bob Roberts page he says the following:
as you can see, like most monitors, it has positions for both positive or negative sync signals from bds. A composite negative output Pac-Man board would connect up as above with both lines tied together
So does this mean that I take the single VSYNC wire (not sure if that means video sync or vertical sync on the jamma harness) and spilit it so it goes to both the positive horizontal synch and negative horizontal synch on the monitor?
-
I now have the sync wire from the jamma adapter going to both the horizontal and vertical negative sync. I still had the same picture as shown in the video.
Being out of answers, I started adjust the horizontal and vertical hold knobs on the monitor. I hate to admit it, but adjusting the horizontal and vertical hold finally got me a picture. Not a good picture, but a picture. Adjusting the focus and the black level helped quite a bit. It still has artifacts througout, but the game is viewable.. and it plays.
Now there are thin, evenly spaced vertical bars running throughout the picture. The game plays, and the colors look pretty good. The bars seem to change in freqency from time to time. These are NOT the classic hum bars. Something else is amiss. None of the repair sites with screen shots seem to be close enough to draw a conclusion. Note that these bars do not seem to affect the maze or the ghosts, etc. They are separate and distinct from the game graphics.
-
Resolved. Adjusting the controls on the monitor got the picture recognizable, but still very jittery. The ultimate solution was connecting the ground post on the monitors pins to the video ground on the jamma connector. Previously I had it just going to a ground on the monitor chassis. The picture is pretty darn good now.
-
Glad to hear it worked out well for you.