K7193 Stumped... Didnt think it could happen

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Ok gents,
I hate to provide another k7000 t-shoot thread but I am fair at repairs on these.

It had jailbars, so I expected a cap kit. After the kit was done and the usual checks for reflow etc I still have the same issue. Jailbars type OVERLAY. I know its not sync, not sure if its a vertical issue or what. This is why I am here!

Ideas welcome on what to do next. Its almost like yellow raster ,but if you turn it down it turns down everything.
 

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That is not jailbars. It looks like the screen setting on the flyback is turned up too high, or possibly one of the color guns is shorted and staying on at full blast.
 
very hard to say over the internet but im thinking...

coarse brightness cranked up too high on the flyback.
when you turn down the brightness to make the lines go away, the pic will probhably be too dim due to a tube issue.

also play with the 50/60 pot and see if it helps

You need to make buddies with a rejuve to test that tube out.
 
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also- let us see how you have the video wires hooked up to this thing. You might have a couple of colors backwarde or mixed up.

from the back of the monitor twoards the front (iirc) it should be red, green, video ground, syncs, the on the 3 pin connector video ground and the other syncs.

aha when all else fails, check the k7000 sticky lol

http://forums.arcade-museum.com/showthread.php?t=139218
 
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judging by the Pac-Man ghosts, it looks like your red is nearly missing. the yellow tint will be generated by a missing red with the green and blue up.

this effectively means you need to start over with the adjustment knobs. turn the flyback down some, turn the brightness and contrast knobs to halfway. then turn the color drive controls all the way down, then turn them back up about a little less than halfway to start with. your color bias controls for red green and blue should be turned all the way down and then to about a 1/3 of the way.

if your retrace lines were eliminated and you're seeing red, green and blue in the picture again, albeit possibly with an incorrect white balance, then you'll rest easy knowing the tube is still ok.

if the retrace lines DO NOT go away after turning all the above mentioned adjustments down, then you're probably looking at what you see: a shorted green/blue and a dead red.

someone else had a problem with their green being stuck cranked way up and the adjustments did nothing on like a K7400 or U5000 or something and it turned out that their jumper hacks on the burned traces were crossed somewhere, so also verify that your drive transistors don't have solder bridges or something too.
 
Ok,
I turned everything back to a baseline, I can clearly see red, green, and blue just not working together. If I turn core bright down everything including lines goes away.

Also I noticed that some kind of charge seems to build up, then dissapate and it goes out of focus for a second, kind of like a slow heartbeat. ( does that make sense?) also I noticed in Bobs Cap kit some voltages were lower than what I removed? What is up with that?

This is what I get now.. also that heartbeat is now making some kind of shorting noise at the board. I am betting you are onto something regarding solder bridge etc. I will pull it back out and look.

Thanks for the help so far.

Also connections RGBG and Sync on 10 are right. This is a jamma multi

Whats with the "melting green" overshot with green?
 

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Turn the lights off and watch the board in the dark. I bet you see a bit of arcing with the shorting noise. This is a sign of a leaking flyback and, if so, that needs to be replaced.
 
Ok so the fade in fade out problem was Uhem... umm... leftovers from the cap kit the compressed air didnt get. I wonder who did that?
In any case now I am getting the same results without the fade in fade out. pic looks like picture still red w lines...

Ok i am chasing demons here. I will order up a get well for this because we are back to shorting .. the flyback has to be cracked or compromised. Can that cause the lines though? I guess the HV probably would?
 
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If the lines are red then it is more likely either a board prblem or the tube itself is internally shorted. The easiest method of checking this is with a rejuvenator, but if you don't have one you can pull the transistor on the neckboard that corresponds to the red and see if the problem remains. You may be able to pull that transistor without fully removing the chassis.
 
Ok so q201 off results in green lines.. lol. I saw spark on flyback as you suggested. I assume flyback is the cause?
 
Flyback is failing if it is sparking, it may be the cause of the over driven color as well but that is not certain.

I'd replace it first and see what you have from there.
 
Whats with the "melting green" overshot with green?

That looks like your Contrast being cranked up too high.

As others have mentioned, you really need to have that tube tested and rejuved.
It appears that you are having to crank the flyback SCREEN and colors way up in order to see much.

Try this.....
Unplug the video signal cable. (NO image)
Set your Brightness and Contrast about halfway.
Turn all the color Drive and Cutoff pots all the way counter clockwise. (off)
Set the flyback Screen control "just" until the screen begins to brighten up and then turn it down again "just" until it becomes pure black.
Set all the color Drive pots just a tad up. (1/8 turn)
Adjust each color Cutoff until you "just" see the screen start to turn that color.
If you have to crank a Cutoff way up to see any color, turn the Cutoff back down and bump the Drive for that color up a tad and then repeat the Cutoff adjustment.
This should get everything set to somewhat of a baseline.....
Plug your video signal back in.
Adjust only the Brightness and Contrast....do NOT touch the flyback Screen control unless absolutely needed.
Adjust each color Cutoff a bit more if need be.
Repeat the process for bumping up the color Drive a hair if it seems like you need to crank up any of the color Cutoffs.

If for whatever reason you have to crank a Drive and Cutoff way up for a particular color, then most likely you have a weak color gun.....time to rejuve.
If you max out the Brightness and Contrast and have to crank up the Screen on the flyback in order to get the picture brighter.....time to rejuve.

Anyone feel free to chime in on my baseline process, I tend to do it without thinking much anymore, not used to writing it.
 
Kevin,
I appreciate your reply and it makes every sense. my issue is, should I bother before a new flyback is installed? I assume a "loss" of HV is going to make me try to drive the brightness harder and in effect may be causing this issue. I know it looks cranked up, but its really not. Its just under halfway on the flyback. As I turn it down all the colors and lines go with it, the liines appear in whatever color is driven furthest.

I can try your method if you think i should before replacing flyback, I just thought I would ask .
Thanks for your help and insight.
 
Yes, I would check the Contrast pot, too. I worked on a K7000 not long ago that had weird issues with the focus and pic messing up if I turned the brightness up or down past a certain level. Turned out that the Contrast pot had a crack in it. Replaced it and my problem went away. (This was a chassis that already had a new flyback...)
 
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