Odd Lines on Monitor

[cack01]

Hi Everyone,

I am attaching two pictures for reference.  When a dark screen is being displayed I will get thin faint white lines along both sides of the monitor.  These lines are slightly sloped downward.  The lines are only noticeable or only appear when the monitor is on and a dark picture is being displayed (Like a title screen). When any amount of color is displayed in the areas the picture looks good.

The board was just serviced by Chad at ArcadeCUP so I have a high degree of confidence that this isn't a board issue.  The board used to be paired with a Simpsons PCB so there were never any dark screens (i.e. no idea if this is a preexisting issue).  Monitor is now being used in a Mame / ArcadeVGA setup.

At first I thought this was a degaussing issue, but wouldn't that cause the colors to be off as well?

Thank you for any insight you experts can give.

[MonMotha]

Probably not the "right fix", but turn down your brightness control.  The picture may be lying, but it looks like it's too high.

[cack01]

Hi, I think it may have been that particular loading screen.  Came home and adjusted the brightness with no improvement. Turning the brightness up actually helped b/c it hides the white lines better.

open to any and all suggestions!!! 

[M.Lanza]

Looks like electronic interference.
I've had similar issues but worse involving an unshielded isolation transformer
mounted too close to the monitor.

Could also be caused by your audio amp, florescent marquee light, or just
AC wiring routed too close to the monitor.

[repetto74]

Has this problem been fixed???
I have exactly the same odd lines on my CRT monitor and do not understand where this is coming from!! If a fix has been found I would be glad to know it

Thanks
Rick

[LaC]

Bump.
 I have the exact same problem on my WG D9204.  Just got a lightly used one and its really the only issue I've been having with it.  Black screens are the worst if the brightness is up.  Turning the brightness down does help, but it never goes away completely.  No amount of degaussing helps.
I do have some speakers in the room but they are about 3 feet from the monitor.  I tried moving them into another room, no help.  The monitor is completely open at the moment and not in a cabinet.
I can't imagine what else might be causing this though.

[LaC]

Bump again.
For sure one of you guys who had the problem has found the reason/solution.
Unfortunately I can't PM anyone (I guess because I'm a new user).
Would someone mind PM one of the people in this thread to see if they got a solution yet?
Thanks

[dgame]

Looks like Moiré Interference Patterns: http://www.displaymate.com/moire.html

[LaC]

Looks like Moiré Interference Patterns: http://www.displaymate.com/moire.html

Yes. I verified that this is exactly the problem.
I noticed adjusting the horizontal and vertical stretch affects the frequency of the pattern. I'm going to try some of the solutions given on displaymate and will post back if I have any success.
Thanks!