WG 25K7193 picture bloom

debaser138

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I've got a WG 25K7193 monitor that had a horrible picture along with no red. It would also bloom when switching between screens, when the screen would have alot of white on it, etc. I hooked the tube up to my B&K 467 and the red gun was way in the red. So I did a clean/balance on it and that fixed the red gun. I also installed a cap kit and removed/reflowed solder on all the cracked solder joints along with the header pins.

The picture looks amazing now compared to how it was previously. Unfortunately the picture still blooms when switching between screens, or when there is flashes on the screen like in Samurai Shodown, etc. It's rock solid any other time. I thought the cap kit would fix this but no go. The B+ looks good at 130v. The flyback looks fine and isn't making any crackling sounds or sparking.

Any ideas what would be causing this?
 
did you replace the filter cap.
that can cause the blooming problem.
also the fly will cause it to if it has wight nobs replace it now!!.
i have seen the black nob fly's cracking also lately. the last few i did were cracked.

changing the fly and filter cap fixed the blooming issues for me.

Peace
Buffett
 
did you replace the filter cap.
that can cause the blooming problem.
also the fly will cause it to if it has wight nobs replace it now!!.
i have seen the black nob fly's cracking also lately. the last few i did were cracked.

changing the fly and filter cap fixed the blooming issues for me.

Peace
Buffett

I swapped out the flyback with a new one but that didn't fix the blooming problem. The original flyback didn't have white knobs, they were black.

Which cap is the filter cap and what is the value on it?
 
your B+ is a little high.....you post 130vdc.... the regultor is marked for 123vdc
 
as far as i know a 7193 is a 25" and that is the correct B+.

a 19" is B+ 123v

we need to know what size his monitor is to be sure.

pending that his VR could be bad.

Peace
Buffett
 
I replaced the filter capacitor (550uf 200v) and no change. I also tried replacing the 2N3904 at Q8 per cbuschief's recommendation and that didn't help either. The screen is still blooming a bit when the whole screen image changes. It's really noticeable when the entire screen is white. Otherwise the image is rock solid.

Another thing I noticed tonight is that on the right hand side of the screen from top to bottom about 1" out it's a blueish color. It's really noticeable when a game has a black or white background, like the Neo-Geo screen and Winners Don't Use Drugs screen. Perhaps it needs to be degaussed.

Any other ideas?
 
try this

some times your brightness, screen and contrast are up to high.

turn your brightness and contrast down.

adjust your fly till the raster lines disappear and it just goes to black.

then turn your contrast and brightness pots us a little at a time and see how low you can get them for a good picture.

as an out of balance between all of them will cause it to bloom like that.

also some games will bloom no matter what. it is the color change from wight to black screens that do it to all monitors in varying degrees.

i have some games that do that to any monitor i hook them up to. and the chassis are working properly. tekken is by far the worst for making a monitor bloom during the screen changes and the intro.

Peace
Buffett
 
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Yeah, I already did all that. The picture still doesn't seem as nice and bright as it should be. Don't get me wrong, the picture looks good but when I compare it to another WG 25" monitor in a MK2 cab I have here, the MK2 monitor is so much brighter and crisp. Could be the tube but my B&K 467 shows everything is good after I did a clean/balance on the red gun which was way in the red when I first hooked it up.

I think I'm going to just write this off "as good as it's going to get". Alot of it might be me just being really picky. Most people would probably never notice it.

Thanks again for the help guys!
 
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