Help Please, Cocktail Monitor Troubles with pics

SpartyMAC

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Ok I have a Midway Cocktail with a WG 4900 in it and I can't figure out what is causing the colors to fade on the left hand side of the screen when I close the lid. If I have the lid open or even just open about a 1/3 of the way the picture is PERFECT. But when I close the lid the it seems like the Red fades away.
Things I have tried.
1. Bought new Shielded Iso Transformer from Bob.
2. Tried leaving the Iso Transformer outside the cab just to see if I would get the same results and I did.
3. Removed the speaker from the cab, same results occured.
4. Ran it with the power supply/board and iso transformer outside the cab and still had the same results.
5. I have also just let it run for a few hours and have tried to turn it on and off a bunch of times.

What would cause this?????
Do I need to Degause it while the top is closed? If it's that simple I am gonna kick myself. I don't have a degauser or I would have tried that.

Any suggestions? Thanks

Pic with cab top closed.

3703217418_d214c404a7.jpg


Pic With Cab top open.
3703219476_39fc4d7fee.jpg


Just a pic of the inside of the Cab, wires are loose until I can figure this out.

3703220268_71f50da689.jpg
 
Any time you move a monitor while it's on like that, you will get this effect. Try it right now with your computer monitor. Turn it on it's side - the colors get all screwed up.

All color monitors have a built-in degaussing coil that fires when the monitor is turned on when it's cold. All you have to do is shut off the game, shut the lid, then wait fifteen minutes or so, and turn it back on. The degauss function will engage and the picture should be fine. If you've managed to really screw it up, it may take a couple power cycles.

Computer monitors (and newer arcade monitors) have a degauss that can also be manually activated with a user control. A fun trick to play on your co-workers... turn their computer monitor on it's side and degauss it with the button. Then turn it right side up again. All the colors will be screwed up. It usually takes 'em a while to figure out that they need to degauss it again...

-Ian
 
In the past I've found that if I have the cocktai open and turn the monitor on and close it the colors are all jacked up. I'll shut it down for about 30 minutes and turn it back on and the degaussing mechanism works well enough to clear it up.

Keep in mind Midway had a stiff piece of paper that was stapled on one side of the monitor so when you closed the lid the was a barrier between the monitor and the coin door. That coin door can cause discoloration. So close the lid and leave it off for around 30 minutes. BEFORE you apply power open the coin door and hold/tape the plastic switch and see if you still have this issue.
 
All color monitors have a built-in degaussing coil that fires when the monitor is turned on when it's cold. All you have to do is shut off the game, shut the lid, then wait fifteen minutes or so, and turn it back on. The degauss function will engage and the picture should be fine. If you've managed to really screw it up, it may take a couple power cycles.



-Ian
I must have really screwed it up :) because I tried that a bunch of times.

Thanks guys, I guess I will be putting an order in for a coil. I have been meaning to get one and I guess this gives me the reason to purchase it.
 
I don't see the shield being used in your pictures - buy a coil if you want BUT if that's the cause the issue will reoccur.

Secondly - your pictures also lead me to believe your yoke is twisted - the picture appears slightly off kilter.
EDIT: Maybe not twisted I downloaded the pic and increased the brightness. Looks like your picture isn't centered from top to bottom which also creates the white line found on the bottom of your screen.
 
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another thing that worked for mine when I had a similar problem was to change the position of the ground wire on the neck board. I know it sounds crazy but it worked. There are two spots for the ground wire to attach. Try the other one.
 
Keep in mind Midway had a stiff piece of paper that was stapled on one side of the monitor so when you closed the lid the was a barrier between the monitor and the coin door. That coin door can cause discoloration. So close the lid and leave it off for around 30 minutes. BEFORE you apply power open the coin door and hold/tape the plastic switch and see if you still have this issue.

Now that sounds interesting since it is the side next to the coin door that goes funky. I am gonna just take the coin door off tonight just to see if thats it. Does anyone have a pic of this shield? or know where I can get one. This is a project that I have been piecing togeather for the past year. I found the cab in someones trash and it was missing pretty much everything. (no boards, no monitor, no power supply and no Glass) I aslo am going to get a degausing coil since I should have one around anyway.

Thanks again for all the get input.
 
The shield I speak of is a simple thick piece of paper that is stapled to the underside of the top wood and hangs down in between the monitor yoke and the coin door. You can go to any arts and crafts store or even possibly walmart and pick up something to use.
Try the coin door trick I mentioned first before you spend the .49 cents ;)
 
I'm surprised no else has mentioined that the PC power supply in the bottom near the trouble area could be your problem.
 
I'm surprised no else has mentioined that the PC power supply in the bottom near the trouble area could be your problem.

.He stated in opening thread - "Ran it with the power supply/board and iso transformer outside the cab and still had the same results."

And thanks I couldn't remember the name of the "interlock" switch heh
 
I'm surprised no else has mentioined that the PC power supply in the bottom near the trouble area could be your problem.

I had thought that also, but I did try it with the power supply sitting outside the cab. I can't wait to get home and try some of these suggestions out. I want to get this thing done. :)
 
That giant piece of "fishpaper" used as a shield in front of the monitor chassis is there for two reasons: to keep your hands/arms from touching any live electrical contacts (especially the high voltage wire on the picture tube) and to prevent kids from spraying liquids through holes in the coin door onto the monitor.
 
it is prob the thing i read along time ago
that cocktail monitors and their color can be like your pics due to the earth's magnetic field
try rotoating the whole cab 90 degrees and see if it fixes it

this did happen to mine too so i have it in my basement in a area where it looks perfect
 
That giant piece of "fishpaper" used as a shield in front of the monitor chassis is there for two reasons: to keep your hands/arms from touching any live electrical contacts (especially the high voltage wire on the picture tube) and to prevent kids from spraying liquids through holes in the coin door onto the monitor.


Ahh well that would have been a nice feature to have about 2 weeks ago when I stuck my hand in there to adjust something and shocked the crap out of myself. Two nice burn marks on my finger later and I think I have learned my lesson. I will now make sure to add the cardboard just for that reason even if it doesn't help with fixing the picture. Thanks
 
Well after going through everyones suggestions it actually turned out to be the cheapest one that fixed my issue. I have had this cocktail sitting in the same position while I have been working on it for the past couple of months and never thought of just trying to rotate it. Well thanks to Doc suggestion all I needed to do was to turn the machine around 180 deg. I really can't believe it was that easy but the picture now looks great. thanks for the help everyone.
 
That thick paper doesn't really have magnetic shielding properties...as Ken stated....it's to keep your hand from getting bit :)

Edward
 
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