K7000A Horizontal Lines?

Jdurg

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Okay, I have a spare K7000A chassis that was giving me a jumpy, faded, poor quality image. I went and replaced the flyback and VR on the chassis since the symptoms it was showing indicated that one of the two was starting to go. (Kept the old flyback just in case).

When booting up, it looks 10 times better than it did before. It now fills the screen, has great depth and contrast, etc. Problem is, there is now a new problem.

There are horizontal lines right in the middle of the image as seen below. What could cause this? The chassis itself is in pretty rough shape as there were jumpers needed due to the Voltage Regulator pads being absolutely destroyed from prior damage before i received it. I jumpered these properly, but don't know what the issue is with it. Any help would be great because otherwise this looks incredible.

IMG_1341_zpsdzfy5hlq.jpg
 

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do you get that with another game board hooked to it? have you tried the monitor in another cabinet or another monitor in this cabinet to make sure the problem is 100% in the monitor and no where else?
 
Unfortunately, I have but one cab and this one monitor. (Have a Dynamo HS-5). I tested out on other boards i have and it's the same issue in the same spot on the monitor. If I could get this to go away, this would look beautiful.

The work I did was replace the old Zenith flyback with NOS, replaced C38 with a .330 cap to increase screen width, and replaced the old VR. On the VR, I did have to jumper some legs because the pads were shot to all hell and burned off when I removed the old one. (There was some pretty bad damage to the monitor board when I got it in this general area).

Prior to all this, the chassis worked but the image was small, dim, wavy, and VERY jumpy and bloomy. This was after a cap-kit initially to get it working.
 
If you had bad pads and had to jumper on the VR, there could be others that may need to be repaired (especially on the caps).

I had a GO7 that had a similar problem and one leg of a cap in the horizontal section had a pad that was not making contact to the trace.

So look over all of the caps and check for continuity from each leg (pad) to the next pad on that trace.
 
I'll pull the chassis out this evening and take a close look. There was a PP cap on the backside of the chassis that was attached to one of the points i had to de-solder in order to get the flyback out. I'll take a closer look at that area to see if there is something that perhaps I missed.

On the VR, I did notice that it appeared as if one leg isn't connected to any trace. This was before I had removed the old one. Just wondering if this is normal as this chassis doesn't have traces on the top.
 
Yes, i am very certain about that. The thing is that the strange lines are "fixed" in place. If I adjust the vertical position or size, the deformaties remain in the exact same spot on the screen. Kind of frustrating as it really looks amazing with the new flyback and VR on there. So even though I do have another chassis, I'd like to get this one running perfect as well so when I get around to working on another cab I'll know I have a fully working 25" monitor to put in it.
 
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