jjhudgins
Well-known member
Any luck here
K7000 red overdriven
- Thread starter curtislv426
- Start date
OP
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jjhudgins
Well-known member
I have the same issue and the same results. kind of. Red was way over driven. I have built a brand new neck board and I know it works well. I also have several working remote boards as well.
I replaced d5 and q1 and the bipolar caps. I already replaced the caps beforehand. The red overdrive is evident on every screen that's requires red. Blue and green looks good. Just so strange. Qq1 did test bad. I also have the k7000 with the vertical board and c7 is moved to the left right below ic1. Replaced IC1 with same issue.
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I just fought one of these.
I put a test pattern on screen with red green blue white color bars.
I dialed blue and green drive and cutoff dials all the way down.
I put the red drive and cutoff about 3/4 up.
Then I adjusted brightness and contrast on the chassis remote board and the brightness on the flyback until the red color bar was good.
With the red correct it was now very easy to dial blue and green back in
I put a test pattern on screen with red green blue white color bars.
I dialed blue and green drive and cutoff dials all the way down.
I put the red drive and cutoff about 3/4 up.
Then I adjusted brightness and contrast on the chassis remote board and the brightness on the flyback until the red color bar was good.
With the red correct it was now very easy to dial blue and green back in
OP
OP
Than
Thanks. I am very comfortable color balancing monitors. This is definitely a chassis issue in the red circuit
jjhudgins
Well-known member
Let me go try this again. Usually all the neck board pots can be halfway and you are good. think I tried this.
If I knew how to read the red color circuit schematic correctly I would pull every component till it's fixed.
Help here
My neckboard is new. It works flawlessly in other k7000 chassis.
If I knew how to read the red color circuit schematic correctly I would pull every component till it's fixed.
Help here
My neckboard is new. It works flawlessly in other k7000 chassis.
OP
OP
Check Post number 13 which is my post and click on that link to the high resolution image and you can see the red circuit that I followed. Hopefully that'll will at least help you. LolLet me go try this again. Usually all the neck board pots can be halfway and you are good. think I tried this.
If I knew how to read the red color circuit schematic correctly I would pull every component till it's fixed.
Help here
My neckboard is new. It works flawlessly in other k7000 chassis.
jjhudgins
Well-known member
Found it. Lifted trace on c13 leading to the brightness pot Vr 6.
OP
OP
Way to stick with it. I had to move on for other projects of higher importance. Once I get caught up I will get this one back on the bench.
OP
OP
I heard ya the first time. Lol
Ever figure this one out? The K7000 in my Joust 2 is bleeding red unless I turn the both red pots to basically zero. It's super touchy, and I absolutely positively can not find a way to adjust all the pots so that black is black and all the other colors look some degree of okay. Red is the only color that has a crazy bleed problem.
Monitor is recapped, all pots and headers reflowed, and has new flyback.
Monitor is recapped, all pots and headers reflowed, and has new flyback.
OP
OP
I have this chassis set aside. I'm going to send it to zenomorp if he's cool with that so that I/we can get closure on this and hopefully it will help you and the other fella on here who also expressed an interest.
I've had a similar issue:
K7000 Too blue baby, I hate you.
Sanity check. Looking at the white gradient pattern, screen looks too blue. Generally this should be a neck board or mainboard transistor issue where there is too much blue or not enough. Interestingly, other patterns like the white checkerboard is perfectly white, which we know is all 3...
forums.arcade-museum.com
Interesting. I'll look at the transistors next time I pull out the game. I also noticed that when I turn it on, the contrast is weird, and the entire screen is too bright, having the background black at a soft grey. It darkens up over a few more minutes to black.
