Are these jail bars? K7131

LordRyGuy

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I have these two vertical bars on the left side of the screen.. I had just one before doing a cap kit today.. There was one cap that I didn't replace (C56 - 22uf 160v). Could that be the cause of these bars? Or is there something else that causes this? It's a Wells Gardner 25K7131

DSC00020_zps02097892.jpg
 
change both and see if the problem goes away.

C56 is a very important cap.
and your filter cap is the first cap that voltage flows thru after it has been rectified into DC.

Peace
Buffett
 
Looks kinda like jail bars.

Capacitor C56 is a high failure item in the k7000 series. If you did not replace it, then please do so now.
 
I would have replaced it last night but I don't have the right value cap... I'll pick one up today or tomorrow.. I do have the filter cap that I can replace today.
 
One other thing... This is the first time dealing with a K7000.. I'm much more familiar with the U2000 U5000 K7500 K4900.... There is a daughter board on my K7131. It says 85x0314 P609 ... There is nothing actually connected to this board.. It has 2 caps, 2 diodes, and 3 resistors with an input for p1, p2, and p3 .... Anyone know what this thing is/was for?
 
Ah I just replaced both caps in question and it didn't fix the issue...... Damn... Think this is still a cap problem? I can start replacing the non electrolytic caps on the board.. I just don't know which circuit to start with? Video? Vertical? Horizontal?
 
that little board does do something but what is unknown.

i have had many chassis like that and just remove it and toss it in a box.

turn down your brightness and see if that affects it.

then if that does not do it, remove the video signal and see if they are still there.

your tube may have a slight bit of burn in the tube.

Peace
Buffett
 
Thanks for all the help. I really appreciate it.. I installed a new flyback yesterday and had to re-adjust the screen, brightness, and contrast and those lines are visible no matter how dark I try to make the image (unless it's too dark to see anything obviously).. I disconnected the video input and i can still see those lines on the grey screen that appears... They don't appear to be burn-in...
 
try the monitor in another game.

i have seen this phenomenon before and when i switched games it disappeared:confused:

for the most part check your work look for solder splashes and bent pins from other components that may have been knocked in the repair process.

this includes the top and bottom of the chassis.

Peace
Buffett
 
I tried TMNT, Sunset Riders and UMK3. Lines are present every time.. I also have to note that the lines stay static when I adjust the image left and right. I still don't think it's burn in though... I had only one line before I did the cap kit/flyback replacment last night. I also put a flash light to the screen when it was off and didn't see any kind of phosphor burn. I guess I should get another 7000 chassis to test. But in the mean time I'll check all the solder points ont he board and probably start randomly replacing other caps.. I have nothing but time and patience and I will beat this thing! =)
 
sounds good.

be sure to post all your findings for others to use if they encounter similar problems.

good luck!!

Peace
Buffett
 
You might want to try reducing the horizontal size of the screen. WG chassis don't like to produce a picture thats full screen (or even bigger than the screen as shown in your picture).
 
that little board does do something but what is unknown.

i have had many chassis like that and just remove it and toss it in a box.

turn down your brightness and see if that affects it.

then if that does not do it, remove the video signal and see if they are still there.

your tube may have a slight bit of burn in the tube.

Peace
Buffett

came across that little board recapping this 7193 i have here, I'm debating on recapping it tho if it does nothing and is hooked to nothing i figure why bother. I will however be leaving it where it is. I thought maybe it was spare parts but then why bother with the traces on the back.

this isn't the little board that's sometimes soldered to the center of the PCB on some k7000s is it? (P7 maybe??)
 

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i have never seen that board hooked to anything.

i take them off and toss them in the parts bin.

altho i have never used any of the parts on them so i guess my collection will keep growing.

Peace
Buffett
 
maybe there was intent to make a med res 25 inch k7000 that WG scrubbed early on. I base that on nothing just hypothesising.
 
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