WG K7000 Goes Pop!

ManiN

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This guy's got a WG k7000 he aquired and worked fine until... He thought the screen was upside down for his mame setup and thought he'd rotate the yoke to correct it. He said he heard a pop and it doesn't work now. Do any of you guys have an idea of what might have happened. Is it possible the tube was blown? I've had arcing / pop while rotating the blue adjustment on a monitor I have, but it didn't die like this.

Let's assume no electric components simply grounded out as a result of touching something while rotating i.e. a cap on the neck board.

Thanks!
 
ummm

First of all...don't EVER rotate the yoke connections with the power on.

If you heard an audible 'pop' my guess is you blew your flyback transformer, or if you're lucky a tuning cap.
Check the casing of the flyback for cracks.
This likely also means the H.O.T and fuse are blown.
 
I'm willing to bet that when he "rotated his yoke connector", he plugged the vertical into the horizontal and vice versa. if that is the case, then the POP was most likely the yoke blowing, and maybe the voltage regulator, etc...
 
Yoke connections

On many of the 7000 series the spacing on the vertical and horizontal connections is different so the plug can't be swapped. I've seen them cut in two on single plugs so you can flip either the vertical or horizontal, but the two sections have a different spacing so they still can't be swapped.
Also after re-reading your post I'm unclear as to whether he rotated the connections to the yoke, or the yoke on the neck itself?
What model 7000 is it?
 
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I need to talk to him to make sure, but my assumption was that he rotated the yoke to rotate the picture. I don't think he disconnected the neckboard and connected it 180deg diff. Not sure you can even do that as they are keyed to prevent it are they not?

I'm wondering if you are right in that the flyback went out. He said it has a newer cap kit someone did and I bet they didn't do the flyback, so maybe it was blown after a minor mishap where most would have been fine like in the case when mine popped after rotating the yoke.
 
I have a picture of the front of the tube with minor burn, and it shows this unit was displayed horizontally. Makes me realize he was trying to change it to get it to show vertical.

Is it possible to make this a vertical monitor, or will it always be horizontal?
 

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you do not rotate the yoke to display a screen vert you rotate the entire monitor frame and all
you cant display a vert picture on a horz mounted monitor and vice versa


the only thing fliping the yoke wires does is allow you to flip /or reverse the screen for games that output upside down or for running a monitor on a game that uses a mirror
 
So are you saying you could never use this monitor in a pac-man for example? It will always be horizontal? This guy was trying to get it to rotate so he could use it in his Ms. pac cab.
 
So are you saying you could never use this monitor in a pac-man for example? It will always be horizontal? This guy was trying to get it to rotate so he could use it in his Ms. pac cab.

Of course you can. The PCB sends out the monitor orientation signal. The monitor just displays it. You have to have the correct frame is all.
 
I'm tracking now... Ok, I think where the problem lies, is in this guy was trying to use this in a mame setup, and the signal was in a horizontal orientation. He thought he'd correct it by rotating the yoke instead of rotating the signal from the computer.
 
no im saying that the monitor itself has nothing to do with playing vert or horz

the game board is what sends the signal to display vert or horz
the only thing you have to do is rotate the entire monitor

say you have a game with a horz monitor in it that was playing a game like mario brothers wich is a horz game
if you wanted to play donkey kong (or any other vertical monitor game ) all you do is remove the horz mounted monitor and reinstall it so that is is verticaly oriented


all fliping the yoke wires does is flip/reverse the screen left to right and up and down

in theroy you could rotate the yoke on a horz mounted monitor so that it would display vertical but it would look like ass and prob;ay cut off most of the top and bottom of the screen immage

if you notice the monitors are not square
this game has a horz mounted monitor the long er part goes from left to right
http://www.klov.com/game_detail.php?game_id=8951
this game has a vert mounted monitor
the long part goes top to bottom
http://www.klov.com/game_detail.php?game_id=7884
 
if he is using it as a mame monitor then he has 2 options

either rotate the monitor in the cab so it is horz
or use a front end that supports vert monitors and then use the function in xp to rotate the screen so it is vert as well
 
Gotcha. Somewhere along the line, I think when looking into ##-in-one cards that they announced games are specific to vertical, or horizontal, and must have made my own assumption that the monitor used was specific to that direction.

Thanks for the clarification!

he's using a computer CRT now. I think i'll buy this one from him in hopes to repair it to use in a dedicated vertical cab.
 
Well, I bought the monitor and brought it home. I looked around for any fried components and found none. I got a clearer explanation on what he tried to do. He tried to change around the red, blue, green, and yellow wires to 'flip' the yoke. The only wires that appeared to be changed when I looked at it were the red for the blue and blue for the red.

I unplugged them and hooked up power for a bench test. Upon power, there was no noise or anything. I did however notice the large resistor on the outside of the chassis at 220ohm was heating up like a toaster. I unplugged it and checked the resistor for it's resistance (in circuit...) and read ~209ohms so apparently not smoked. I am now wondering if just the flyback is toasted. There is a tag saying the chassis was recapped in Feb. of 09. I've heard after capping, if you don't do the flyback too, it can go at any time? Is there a way to bench test the flyback? Didn't see any cracks in it's case...

Also, I looked at the yoke and checked for continuity between the windings and found yellow and green has continuity, blue and red has continuity, and also a 5th post in the middle of all them connects yellow and green. This makes sense with Bob Roberts yoke coil diagram. Is there another way to check the yoke without costly equipment?

I'm hoping all that is wrong is the flyback, but can't afford to throw money at it unless I'm pretty sure it will fix it.

Any help is greatly appreciated.
 
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