yoke tabs

spisi

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So, my 19V2000 needs to be adjusted. The picture is too far to the right. I was told to adjust the yoke tabs. I've looked for them, and searched but I can not figure out exactly what they look like and where they are. Can someone point them out to me please?
 

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Don't listen to whoever told you about 'yoke tabs'

step away from the yoke. Search how to center image on B&W vector.

I'm the one who told him about yoke tabs. Because in this case that's what's needed.

Either that, or the yoke itself isn't straight. But most b/w vector's (and Asteroids Deluxe in this case) don't have centering adjustments via pots. If the image isn't centered, the yoke must be adjusted.

@spisi, with the monitor off, check to make sure the yoke hasn't loosened up. If there's play, you can loosen it via the screw clamp on the yoke (which holds it to the neck), adjust the yoke back closer to the center, then tighten it back up.

Beyond that, there are two metal tabs on the back of the yoke. They can be rotated around, which will change the centering of the image. However this adjustment will only move it a relatively small amount. In your case I suspect more that the yoke itself has shifted, and isn't centered.

If you're going to try to do any of these adjustments with power on (which is the best way, but also the most dangerous), you want to make sure NOT to touch the anode wire, or any of the yoke wires. You can do it, you just don't want to be wearing any jewelry while you do it, and always be aware of where your hands are. And do it in an environment that is free from distractions, where you can focus 100% on what you're doing.

1734475661773.png
 
I'll first try with the monitor off and see what happens. So, i grab the white circular ring and turn it?
 
The yoke is the whole assembly below. See if there'a any side-to-side play in it, closest to the tube, since it's clamped closer to the end of the neck, and there are usually rubber wedges between the front of it and the tube. But they sometimes fall out. Or the yoke can just loosen and move in transit.

If there is play, angle it more toward the center, making up for the direction it's shifted too far in. Then power back up and see where it's at.

1734476511856.png
 
ok, so not much play, that is I can move the portion that sits in the white ring just a little bit (less than 1/8"). Moving that had no affect to the image. Everything else seems tight. I see the two tabs now...
 
I'm the one who told him about yoke tabs. Because in this case that's what's needed.

Either that, or the yoke itself isn't straight. But most b/w vector's (and Asteroids Deluxe in this case) don't have centering adjustments via pots. If the image isn't centered, the yoke must be adjusted.

@spisi, with the monitor off, check to make sure the yoke hasn't loosened up. If there's play, you can loosen it via the screw clamp on the yoke (which holds it to the neck), adjust the yoke back closer to the center, then tighten it back up.

Beyond that, there are two metal tabs on the back of the yoke. They can be rotated around, which will change the centering of the image. However this adjustment will only move it a relatively small amount. In your case I suspect more that the yoke itself has shifted, and isn't centered.

If you're going to try to do any of these adjustments with power on (which is the best way, but also the most dangerous), you want to make sure NOT to touch the anode wire, or any of the yoke wires. You can do it, you just don't want to be wearing any jewelry while you do it, and always be aware of where your hands are. And do it in an environment that is free from distractions, where you can focus 100% on what you're doing.

View attachment 787784


Why wouldn't it just be the X position pot?
 
X pot grows or shrinks the image in both positive and negative directions
 
So, do I bend the tabs inward and turn the yoke?
 
Why wouldn't it just be the X position pot?

There is no X/Y POS on Asteroids Deluxe. Just two pots for XSIZE and YSIZE.

Color vectors have POS pots. Most b/w's don't. (Except Lunar Lander, but they removed them for all games after that.) Battlezone has locations for POS pots, but they were never populated at the factory.
 
So, do I bend the tabs inward and turn the yoke?

You don't bend anything. The tabs are connected to rings, which rotate.

So when you push the tabs sideways, they should rotate around.

Also, shrink your XSIZE on the game board, to bring the image more on the screen, before you try to center it.
 
OK, much better now, a little bit stretchy along the right and left sides, but I think I can live with this.
 

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The stretchiness is controlled by the X and Y Linearity adjustment pots, which are on the deflection board.

Linearity is like 'size', but only adjusts the outer 3" perimeter of the picture. That allows you to shorten or lengthen just the outer border of the image, so the picture is consistent across the screen. Otherwise, the asteroids will stretch and compress as they traverse the screen.

This is why the test screen is a crosshatch. In this case, you want to decrease the X linearity pot on the deflection board, so the corner-to-corner width of the diamonds is the same at the edges of the screen is the same as in the middle.

Sometimes you'll need to then tweak the size again (on the game board) after setting the linearity. You may need to iterate a few times to get it dialed in.
 
The stretchiness is controlled by the X and Y Linearity adjustment pots, which are on the deflection board.

Linearity is like 'size', but only adjusts the outer 3" perimeter of the picture. That allows you to shorten or lengthen just the outer border of the image, so the picture is consistent across the screen. Otherwise, the asteroids will stretch and compress as they traverse the screen.

This is why the test screen is a crosshatch. In this case, you want to decrease the X linearity pot on the deflection board, so the corner-to-corner width of the diamonds is the same at the edges of the screen is the same as in the middle.

Sometimes you'll need to then tweak the size again (on the game board) after setting the linearity. You may need to iterate a few times to get it dialed in.
Thanks yet again andrewb!!!
 
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