Strange Color Problem

[FrizzleFried]

Alright...so I ended up with Foxen's Xmen vs Street Fighter cabinet he posted about having color issues...

A couple things...

(A) It is NOT a convergence issue...

(B) It is NOT a magnetic interference degauss issue.

How do I know?

Well,  the colors MOVE...when the WINNERS DONT USE DRUGS screen comes up for example...its supposed to be a white background...i get the colors of the rainbow MOVING from outside inward from each side of the monitor for a couple seconds (FAST)...then it moves to the next screen.  Each screen features differnt shades of different colors all moving depending on the action on screen.  I've never seen anything like it in my life.  Even the CROSS HATCH screen is rainbow...that stays the same...for a few seconds...then MOVES (the colors move around) for a second only to stay stop for a few seconds....and then it all starts over again.

Any idea what so ever what in heck is going on?

Here are some pix...



That was with the flash on...here is with the flash off (note the focus issue is the camera...not the screen)



...and here is the crosshair pattern.  Note the colors... they stay that way for 4-5 seconds then MOVE AROUND for a second or so then go back the same way?!?!



These stills do this problem no justice...the moving part is what is really throwing me for a loop.

Notice the color issues on the first screen...blue is red...red is yellow and green is blue,  sort of...strange how red goes from red to blue too?  I wonder if they have the plug in correctly for this monitor?  That wouldn't explain the moving colors problem though?!

[grantspain]

have you tried a different game board yet
i have only seen once a similar problem you describe-that was caused by after a machine was dropped from a van,the problem was the tube shadow mask became detached/damaged

[FrizzleFried]

have you tried a different game board yet
i have only seen once a similar problem you describe-that was caused by after a machine was dropped from a van,the problem was the tube shadow mask became detached/damaged

Yah...I've tried a known good CPS2 game and a multigame board....both have the same problem....so it's surely the monitor....

[Rickn]

Try unplugging the degaussing coil that is mounted on the tube (2 red wires leading to a coil of wire wrapped in layers of electrical tape).

Is the problem still there.

By this I mean does the screen change every few minutes as you described oris it now solid- may be dis-colored but is it is stable.

Rick Nieman
Rick@niemandisplays.com

[FrizzleFried]

Try unplugging the degaussing coil that is mounted on the tube (2 red wires leading to a coil of wire wrapped in layers of electrical tape).

Is the problem still there.

By this I mean does the screen change every few minutes as you described oris it now solid- may be dis-colored but is it is stable.

Rick Nieman
Rick@niemandisplays.com

Movement depends on brightness.  If the monitor is set dark it is stable with colors just messed up.  If i turn the brightness up,  the colors move more and more quickly...they tend to move from outside to the middle.

[grantspain]

thats a weird problem,have you been taking LSD

[FrizzleFried]

Alright...I pulled the degauss wire just in case....and no change.  Same issue.  I even busted out my manual degauss coil and while it (obviously) altered colors while on,  it didn't rectify the situation at all...

I did find it strange that with a normal running monitor if I degauss and "pop" it on and off it will leave "marks" or "spotches" on the screen.  With this monitor the colors seemed to pop back to the messed up area even when I incorporated the "pop" technique.

Very weird.

[grantspain]

without a video signal you get the same problem?
does it look like a messed up rainbow

[FrizzleFried]

without a video signal you get the same problem?
does it look like a messed up rainbow

I will have to check when I have time...I'd imagine I'll have to turn up the screen to take a look.

[Rickn]

So ok, looks like your board has CRT test programs (you showed the crosshatch).

Can you bring up a solid color field like green and show some pics.

Next take the heal of the palm of your hand and "smack" the center of the tube ( or use a rubber mallet).

If the screen color "bounces" - red's blues...

We are likely back to Grant's earlier comments- broken welds on the shadow mask.

These are aggrated when you have the high brightness as this causes the shadow mask to heat and expand and then the changes you describe happen.

If this is the case, the tube is screwed.

Has this monitor been dropped on it's face??

Good luck

Rick Nieman
Rick@niemandisplays.com

[FrizzleFried]

Alright...

First I pounded on the front of the glass... besides minor "jumping",  nothing really happened... nothing out of the ordinary.

I then pulled the input from the chassis and turned up the screen...here is a shot of what I got (keep in mind these colors are constantly jiggling and swaying...)



...and here is a crappy little movie of what I am seeing...

[grantspain]

that looks exactly the same to the shadow mask problem i had all those years ago(about 1989 when nigel dropped a play choice 10 off the pick up truck and it landed on its front),i reckon new tube
on the positive side it looks pretty

[Rickn]

Bad news, I am relatively sure it is the tube. It is likely an open Anode. This is internal to the tube and not repairable.

Hard to be 100% sure as the only time I ever saw it was when I worked at Mitsubishi's television factory as their QA/Engineering manager.

The only way to be sure is to connect a different tube to the board.

Rick

[FrizzleFried]

Grrr....

Oh well... and this glass has very little burn-in. 

Don'tcha hate what that happens?

Yet another tube to the shitter...

THANKS for the info though guys!

[FrizzleFried]

...---gosh-darn--- how I was hoping to come in here this morning to find that Ken Layton had responded telling me to replace cap # such-n-such and it will fix my problems!

Argh...