K7000 Fold....kind of

MonsterBash

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So I'm about stumped again on this k7000.

This monitor was in a World Class Bowling when I got it. It worked find when I pulled it about 6 months ago. I have a bad tube (no blue gun) in my area 51 so I was just gonna swap the monitors and be done. I hook up the area 51 and got a weird curvy thing going on at the top of the screen. I try for about an hour to adjust it out with no luck.

So in the process of ordering a cap kit my buddy dumps a couple monitors off my bench and they shatter...one was the k7000. I pick up a donor tube from a Zenith TV with a .5 difference in the H and dead nuts V yoke. The yoke was cracked in the fall.

I capped the monitor and install the donor tube... keep in mind I used the donor tube yoke...I still have the exact same problem before capping and the tube swap. I pulled the chassis again and spent a couple hours at work today touching up solders joint on both the main board and the neck board. I'm fairly confident I have them all but still have the problem. I double checked the correct caps and polarity

I went through the k7000 sticky and RF's flow chart..the closest I get from the flow chart it to replace IC2 'substitute' I ordered IC2 and 3 today which I'm waiting on. (what's the substitute?)
Also.. when the Press start 'icon' flashes off and on...the screen actually jump in unison with the free play flash. I've mess with the 50\60 hz pot also. This chassis does have the remote board for the POTs and does NOT have the 'other' board I've read about. It seems removing this 'other' board fixed almost this exact problem for another klover

When I adjust the width coil I get absolutely no response at the monitor..it does nothing. Strangely when I adjust the 'black' the 'fold' actually changes and will flip the other way..the same when adjusting the contrast. Hooking up the old monitor does not have this problem.

Any ideas if this could be related to the yoke? it just seems strange I would have the same problem before the tube swap..and the yoke would be responsible

ETA B+ is 130 and 145 at each end of the resister and this http://forums.arcade-museum.com/showthread.php?t=225434&highlight=k7000 Very close to this issue except I don't have the pin cushion board to remove
 

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Hmmmm... does this have the big long adjustment board? If so, make sure it's plugged in the correct way, if you plug it in backwards it does stuff like this.
 
I'm pretty sure this is the board that I read about. In the only case I found similar to mine removing this board fixed it. My chassis does not have this board. Gonna search again for the post

Hmmmm... does this have the big long adjustment board? If so, make sure it's plugged in the correct way, if you plug it in backwards it does stuff like this.
 
No that's not what I'm talking about.

There's a bunch of wires going to the remote board, that all the pots are mounted on, right? Is yours a little square board with 6 pots on it, or is it a board about 6 inches long?
 
So wiring was correct on the remote board. One thing I mess with in the 15 minutes I had yesterday was the yellow jumper wire. If I moved that to the center position or the 'left' position the picture got WAY better. I now only had a small curl at the top of the screen. There was no getting it out as adjusting the H hold the smallest amount would just flip the curl the other way.


I've read darn near every k7000 post here and I see a coupe people fixed a similar problem by removing the sync wire while the monitor was on..and reinstalling it. I've also read where the k7000 had an issue with a particularity board...and switched the 'curl' monitor to another game and it was fine.

One thing is strange..which it leading me to believe that it might be the yoke issue. The H position (shift) pot is max out to the 'right'..that's when I have the best pic. If I max out that POT..as I'm getting closer to the max it gets better and better. The picture is getting closer to the center..and the 'curl' gets smaller and smaller...then I run out of adjustment. If I try to fine tune it with the H hold...it flips the curl the other way (as stated above).

The H yoke value was the one that was about .5 to .8 off

At this point I'm not gonna change IC2 as I don't think it's an issue.

Other than the sync wire..anyone else got any ideas? I should have some time to mess with it tonight
 
on your synk wire are you only using pin 10 on the input header and only pin 10.

i have seen it when you loop pin 9 and 10 together it will do what your talking about.

Peace
Buffett
 
So this was pretty close. I moved the sink wires from the original location (with the RGB and Ground) to the 'other' pins..the 3 by themselfs and it fixed the problem.

I do have a little degauss issue in the upper right hand corner but it's certainly good enough for me!

on your synk wire are you only using pin 10 on the input header and only pin 10.

i have seen it when you loop pin 9 and 10 together it will do what your talking about.

Peace
Buffett
 

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