g07 screen troubles

corky

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hey all, i have a g07 in a ms pac-man machine that im having a little problem with. the monitor wasnt working when i bought the machine last week - both fuses were blown and f901 blew again after i replaced them. i installed a new flyback, hot, and caps, and now i have a picture! here comes the problem(s)...

first of all, the only color displayed is green, no blue or red. the top and bottom of the screen have a little wave to them that seems to pinch the right side of the screen slightly. there are also brighter, more defined diagonal lines in the picture that "breathe" slowly (move toward the center, then back to the edges of the screen). even though there is now something on the screen, nothing from the game is displayed - no attract screen, no maze when i start the game, nothing.

any ideas what to check first? im including a pic of the offending monitor in the cabinet.

TIA
 

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1) Is the video connector attached to the monitor?

2) Can you coin it up and start a game and hear it play?

It looks like the game isn't running, or isn't connected to the monitor. Have you checked the fuses in the bottom of the cab?
 
looks like you need to adjust the screen control (those lines are there on my monitor until i turn it down). you probably just need to adjust the green cutoff and play with the pots to calibrate.

this advice has helped me well:

- Adjust the Red/Green/Blue DRIVE controls (on the board) to minimum.
- Adjust the Red/Green/Blue CUTOFF controls (presumably on the neckboard) to center.
- Turn up the SCREEN control on the flyback (next to FOCUS) so you see the image and keep going until you start seeing the retrace lines with an overall "fog" on the screen--especially in the black areas. Then back off until it's *almost* black again
- Now adjust each of the DRIVE controls so the level of color is the same in the black areas (e.g. if only blue is lit in the black area, bring up red and green slightly to match the same level to make it grey)
- Now turn down the SCREEN control to make black pure black again.
- Now adjust the CUTOFF controls to ensure that you don't have bleeding of colors to the edge of anything.


as for the game not playing..i'm not sure..it seems like modessitt said, it seems like the game isn't running/hooked up.
 
1) Is the video connector attached to the monitor?

2) Can you coin it up and start a game and hear it play?

It looks like the game isn't running, or isn't connected to the monitor. Have you checked the fuses in the bottom of the cab?

1) i believe so. everything that can be hooked up to the monitor is.

2) yes, the game plays blind. there is just no picture from the game on the monitor.

all fuses in the cabinet are good.
 
There are 5 wires that go to the monitor via two connectors. they connect to the monitor on the middle left side of the chassis....
 
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There is also a 5-pin connector that comes from the neckboard and plugs into the game board near where the other connectors are...
 
There are 5 wires that go to the monitor via two connectors. they connect to the monitor on the middle left side of the chassis....

ha, yeah they are connected. just had a brain fart as to what they were. also in the process of replacing the caps, etc, i inspected the joints and none of them looked cracked or cold.
 
Post a pic of how it's hooked up, and the chassis overall. We might see something....
 
kind of hard to take a decent pic of the chassis hooked up to the tube/cabinet, but i hope these help. let me know if you want me to zero in on anything for a pic. pics of disconnected chassis coming momentarily
 

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here is the chassis in the wild. again, let me know if i should zoom in on anything.
 

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It doesn't particularly matter what you work on. It's a monitor chassis, it's not like it's all that static sensitive.

Anyway, have you reflowed the headers on the video input connectors? Cracked solder joints there are a pretty common problem. Similarly, cracked solder joints on the neckboard driver transistors are pretty common also.

-Ian
 
I reflowed the video input connectors last night to no avail. ill reflow the neckboard ASAP to see if that helps.
 
I can't really see the pictures here at work, so I really can't say what to check. But, I did just re-read the first post. You say that you're not getting any video from the game at all? Then what do you see that's green? Is it just a greenish tinge to the background, or what? Have you tried adjusting the screen control? Turn it up to see if you can get a full raster.

-Ian
 
I can't really see the pictures here at work, so I really can't say what to check. But, I did just re-read the first post. You say that you're not getting any video from the game at all? Then what do you see that's green? Is it just a greenish tinge to the background, or what? Have you tried adjusting the screen control? Turn it up to see if you can get a full raster.

-Ian

I crank the screen control and get a raster, but that's it. Nothing from the game. The raster is also green. Shouldn't it be white?
 
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