Ever seen this K7000 problem

ELutz

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I just finished capping a 25K7000 series......here's what it looks like...Anyone ever seen this issue. The "blob" will slowly shrink as the monitor runs.....until about 15 minutes....it'll be gone. You can (kinda) see it's shrank a bit between my pictures. I do have the brightness cranked high to show the issue better. In the second picture, you can see an additional larger blob......but it doesn't black-out the screen.

Edward
 

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I have something similar on a 13" G07. I haven't done anything to troubleshoot it yet, though. I didn't turn up the raster so I don't know if there is an associated larger shadow with my blob.

Does the larger blob go away when the smaller one does? I have a feeling that the horizontal width is not locating properly and the larger blob is actually the data that should fill the smaller blob.
 
K7000 - change C57 again and see what happens.
(of course check associated grounds and traces and whatnot)

G07 - I think it was C511
 
This chassis actually has a terminal strip mounted on the "wall" beside the flyback.....It's got a resistor and two ceramic caps mounted on it.

Edward
 
I had a similar problem when I bought my tetris but it had a k4900 in it, and it had a dark/dead spot om the monitor till it really warmed up, recapped it and problem was solved, since you recapped yours already check to make sure you have them in the right way. which im sure you have already done ;)
 
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ok if you look the wite wire goes to the spot that i was referring two.
and the red goes to the center lead of the H.O.T.

the components that are there would go in that spot on the main chassis where i was leading you two.

i have tried to place the components back on the chassis and eliminate that little board. it works to a degree but your image size only is the size of a 19" and will not fill the tube.

it looks real good but is small.

you also need a yoke with readings close to 1.5 V and 5.1 H to
properly test this chassis on. thes were shipped from the factory wit theses chassis.
i have a tube here with one of theses on it and it has never been messed with and still has the silicone holding the neck board to the tube. unknown if it works or not i have not had time to mess with it.

theses were used in allot of Konmi games ie, tmnt, simpsions, Ect...
this info was gatherd from wells Technical Specialist John Pruski.

i have talked to wells John Pruski about theses chassis and he remembers making them but could not remember why that mod was used.
he did say that theses chassis get allot hotter than the standard wells chassis and were discontinued.

so i would test the components on the little remote board and see if they are good.

i have around 15 of those chassis here and dont bother to fix them.
i will after i get caught up with others i have.

i do have one of those chassis running in my MVC2 and it looks superb.

Peace
Buffett
 
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Fixed!

As Buffett outlined.....R69 and C28 were cut from my chassis. A white wire was then ran, from these componets location, to a small terminal strip with a resistor and two high voltage disc caps mounted to it. The terminal strip then had a red wire that ran to the center leg of the HOT. This red wire was not making good contact with the leg of the HOT. Cleaned the connection up.....all good.

Buffett nailed it!

Thanks to everyone!

Edward
 
glad i could point you in the rite direction.

i had seen it before on one of my chassis (got it in a lot of unknown chassis from an opp) and had to fix it so that's how i found out.

mine did not have the satellite board it was a standard issue wells but it was missing those parts for some reason, the rest of the chassis was complete minus them.
so a trip to the scrap/parts chassis bin. and 1 more working chassis later.

Peace
Buffett
 
Sweet !
I had never encountered problems with those little satellite boards. Heck most of the chassis I find them aren't even connected at all, yet the chassis worked fine after a typical rebuild.
I'll have to make a note of that one.

The caps I had referred to have been known to cause a similar issue beings it's the bypass capacitor coming off the H.O.T.
 
Sweet !
I had never encountered problems with those little satellite boards. Heck most of the chassis I find them aren't even connected at all, yet the chassis worked fine after a typical rebuild.
I'll have to make a note of that one.

The caps I had referred to have been known to cause a similar issue beings it's the bypass capacitor coming off the H.O.T.

Oh yeah, my original thought.....I had a bad cap in my cap kit.
Just for shits and giggles......I totally unsoldered on end of the red wire and fired up the monitor.......the blob is back!

Edward
 
the one that is not hooked up at all is a different satellite board then the one he has.

i dont know why wells left them on the heat sink as i just remove everyone i come across.

pic 1 is the one he has. with the red and wite wires

pic 2 is the unused board. which i think is the one you are referring two.

there is another K7000 chassis that has yellow and wite wires comming from that satalite board as well. but it is not the same and the two components i was referring two are on the chassis and not on that satellite board.
if i had a pic of that one i would upload it as well.

Peace
Buffett
 

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the one that is not hooked up at all is a different satellite board then the one he has.

i dont know why wells left them on the heat sink as i just remove everyone i come across.

pic 1 is the one he has. with the red and wite wires

pic 2 is the unused board. which i think is the one you are referring two.

there is another K7000 chassis that has yellow and wite wires comming from that satalite board as well. but it is not the same and the two components i was referring two are on the chassis and not on that satellite board.
if i had a pic of that one i would upload it as well.

Peace
Buffett

Yep, first picture is mine. I always thought the satalite board in the second picture (when connected) was a protion of mods to make the K7000 medium resolution chassis, but I could be mistaken.

Edward
 
the one that is not hooked up at all is a different satellite board then the one he has.
i dont know why wells left them on the heat sink as i just remove everyone i come across.
pic 1 is the one he has. with the red and wite wires
pic 2 is the unused board. which i think is the one you are referring two.

Ah... that explains it.
I don't think I have ever come across the smaller one in the first pic, or I've just never paid much mind to it. (I'll have to scrounge through some chassis and look for it now)
The second pic is indeed the one I was referring to.... I always assumed it had been for some sort of minor pincushion adjustment as some I've come across that "did" have wiring always seemed to go down towards where that small header set is for the pincushion boards you'd find on say a 27".

but it is not the same and the two components i was referring two are on the chassis and not on that satellite board.

Gotcha, figured that's what you meant, that they were physically in circuit on the chassis itself.
 
the one that is not hooked up at all is a different satellite board then the one he has.

i dont know why wells left them on the heat sink as i just remove everyone i come across.

pic 1 is the one he has. with the red and wite wires

pic 2 is the unused board. which i think is the one you are referring two.

there is another K7000 chassis that has yellow and wite wires comming from that satalite board as well. but it is not the same and the two components i was referring two are on the chassis and not on that satellite board.
if i had a pic of that one i would upload it as well.

Peace
Buffett

I've worked on one of those K7xxx monitors with the modification in pic 1, in my OMG pizza thread. It was from an Operation Wolf / Golden Tee cab converted monitor:

http://forums.arcade-museum.com/showpost.php?p=1332201&postcount=33
 
I'm so thankful that this thread popped up. I've been scratching my on this one. I could get it to go away by cranking up the height, but that's just not right.

It's missing the large cap. So, the whole thing is electrically isolated.

Can anyone tell me what the markings mean? 3KV I'm assuming is 3 Kilovolts. 270J? R3L?

Plus, note the smaller cap on the right, that's not like the other. The solder appears to be factory.
 

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I'm so thankful that this thread popped up. I've been scratching my on this one. I could get it to go away by cranking up the height, but that's just not right.

It's missing the large cap. So, the whole thing is electrically isolated.

Can anyone tell me what the markings mean? 3KV I'm assuming is 3 Kilovolts. 270J? R3L?

Plus, note the smaller cap on the right, that's not like the other. The solder appears to be factory.

3KV = 3000 volts
270 = 27 picofarads
J = 5% tolerance

R3L = ??? probably a batch code or a date code....unimportant

Edward
 
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