Tube Swap guns drift?? When orientation changed?

JoeB1355

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so I have a wg7000 I swapped the tube in since the original was broken

I swapped the yoke etc. I tested it on the floor in the horizontal position adjust with a centipede looked great.

I put in my 1943 and upper right corner colors are whack so I pull it out test in centipede and its great

then on a hunch I turn it side ways like it was in the 1943 then a big color blotch in the corner!!

The internal guns aren't supposed to move are they?!?

So I pull off the rubber wedges adjust the yoke in the vertical position and it looks great!

I sit the monitor back to horizontal and color blotches

So I figure who cares its good vertical. Which is what I need. I put it in the game leave it on for an hour colors are good but now bottom 2 thirds are blurry and top is still nice and clear.

so WTF are TV tubes not fixed internally? so they don't work if you wanna use them vertically?

or is this just a whack tube? Anyone else have this issue? and yes the yoke is fixed with the wedges glued back in place so its not moving when I change the monitor orientation.
 
You are describing "gaussing".

You need to "de-gauss" the monitor AFTER it is in its final resting position. (quit flip flopping it)
A properly working built in degauss will only work after the monitor has sat cold for a while. When you fire it back up it should begin to degauss itself. Might take a couple times, otherwise you will need to manually degauss it.
 
The Earth's gravitational field is most likely afftecting your monitor. You'll notice this especially if you move the monitor while it is on. Go from horizontal to vertical and you will see the change occur "gaussing".

Cocktail tables are especially prone to this because people will flip the top or lift the monitor to work on the boards and then when they lower the monitor back in the colors are whacked.

With your monitor off (and if it is to be vertical, set it in its vertical position and move the arcade cabinet into its (or near) final position. Leave the monitor off for a bit before powering back on - degauss should occur when powerd up from a "cold" state and you should have a fairly clear picture. If you've been messing with the yoke position, you might have to either move the yoke forward or back on the tube to get rid of the discoloration when you have the game in its final resting spot.

I have a vertical WG7000 that usually rests on my garage floor under the workbench. If I power it up to test a game for a while and then move it up to the workbench after using it on the floor, it is usually discolored and blochy.
 
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I have degaused it in place -- no fix.... only adjusting the yoke fixes it.

I have another wg7000 that doesn't have this trouble horizontal or vertical

and I can't expain the blurryness after an hour. I check again and its really just the center bottom and top are still nice and clear (bottom and top are really left and right in vert pos)

its starts crystal clear everywhere

I guess I need to try another tube -- doesn't sound like other folks have had this issue.

a bad flyback couldn't cause the blurryness in the center could it?
 
The Earth's gravitational field is most likely afftecting your monitor. You'll notice this especially if you move the monitor while it is on. Go from horizontal to vertical and you will see the change occur "gaussing".

Ahem. I think the word you were looking for was "magnetic". As in, "The Earth's magnetic field". I sure hope that was a typo...

:D

But yes, the problem you are seeing is *magnetic* interference. The degaussing coil is nothing more than a n AC powered coil, which generates a varying magnetic field. As the tube is moved throughout the Earth's static magnetic field, the shadow mask gets slightly magnetized. The degaussing coil just demagnetizes it for you. You can also buy/make a simple handheld degaussing tool, so you don't have to shut the game off and wait for the thermistor to cool down so you can use the built in one again.

-Ian
 
I have degaused it in place -- no fix.... only adjusting the yoke fixes it.
Did you degauss right before you set the convergence? If you didn't, then your color purity would have been off from the get-go, and your adjustments would have all been made to compensate for the current state of the monitor.

and I can't expain the blurryness after an hour. I check again and its really just the center bottom and top are still nice and clear (bottom and top are really left and right in vert pos)

a bad flyback couldn't cause the blurryness in the center could it?

A bad flyback can most definitely cause blurryness in the center. The focus pot is a well known failure point in K7000 flybacks. Is this an original flyback, with the white knobs? If so, then that's your problem. The later black knob flybacks fail like this too, it's just less common. If you look closely around the focus control, you may see tiny little cracks in the housing around it. The "gets fuzzy after it warms up" or "is fuzzy until it warms up for a half hour" is a common symptom of a failing K7000 flyback.

-Ian
 
Did you degauss right before you set the convergence? If you didn't, then your color purity would have been off from the get-go, and your adjustments would have all been made to compensate for the current state of the monitor.



A bad flyback can most definitely cause blurryness in the center. The focus pot is a well known failure point in K7000 flybacks. Is this an original flyback, with the white knobs? If so, then that's your problem. The later black knob flybacks fail like this too, it's just less common. If you look closely around the focus control, you may see tiny little cracks in the housing around it. The "gets fuzzy after it warms up" or "is fuzzy until it warms up for a half hour" is a common symptom of a failing K7000 flyback.

-Ian
I did all the yoke adjustments with the power on and a rubber glove ;>


Definetely the orginal flyback. I escpecially was suspecting it since it took an hour or so to become blurry its perfect for 10 minutes or so when I power it up. I already did a cap kit but not a new flyback. I did however resolder the flyback since I've had that trouble before on a WG7000 that would cut off and on with another monitor.

I'll try the chasis off my good one and see to be sure. Thanks
 
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