Per-color size, for convergence?

hackbar

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I'm doing convergence, and I have a problem. The scale of the colors isn't constant, e.g. when I line up the blue & red at the top, the bottom is horribly aligned.

I can adjust h-size for the whole monitor, but I really just need to do it for one color. How do I do that?

This is a Vision Pro MTG-1201CN.
 
usually this means the yoke needs to be adjusted. direct view tubes rarely (never in arcade monitors) offer this type of convergence like projection TV's. Sometime convergence strips can correct some of this.

Did the yoke get moved or any convergence strips fall off?
 
usually this means the yoke needs to be adjusted. direct view tubes rarely (never in arcade monitors) offer this type of convergence like projection TV's. Sometime convergence strips can correct some of this.

Did the yoke get moved or any convergence strips fall off?

I don't know. I'm working on a machine at work, and I don't know the history. I wouldn't think the yoke got moved, since that takes some effort.

I'll check the strips too. I know we have a good guide for convergence, is there anything for the strips?
 
a pic of the cross hatch screen would help.

has the tube been replaced? If what you say is accurate their is a 99% chance the yoke needs to be adjusted. Some monitors have convergence tape magnets on the tube above the yoke on the bell of the tube. This is also very rare. Look for anything that would have been on the tube and left sticker residue. Are all 3 yoke wedges still on the yoke?
 
Here's some shots of the dots test pattern.

The order is

full view
center
upper left
upper right
lower right
 

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lower left

And two shots of the tube. There's no strips, or any evidence of the strips, but the yoke has 3 tabs wedged in. All are taped on, and look pretty nice. I don't know when this tube was replaced, but I can't imagine it's the original.
 

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looks like you need to adjust pole magnets (the ones on the neck of the tube)

you need to read the convergence sticky at the top of this forum.

Yoke might need adjusting too but use the instructions first.
 
looks like you need to adjust pole magnets (the ones on the neck of the tube)

you need to read the convergence sticky at the top of this forum.

I did that, and got it best I could. The problem is I can get the center of the screen to line up, but not the edges. Or I can do the bottom, but then the top looks awful.

Am I doing it wrong?
 
I tried to do convergence again today, and I'm still stuck.

The colors aren't offset the same amount. If the red and blue to line up horizontally at the left side, they will be way off on the right side. How do I fix this?
 
I did that, and got it best I could. The problem is I can get the center of the screen to line up, but not the edges. Or I can do the bottom, but then the top looks awful.

Am I doing it wrong?

Well, you're supposed to line up the center first.
Then you line up the edges by cocking the yoke. Are you doing that part?
 
Well, you're supposed to line up the center first.
Then you line up the edges by cocking the yoke. Are you doing that part?

No, I haven't touched the yoke. I've been following the sticky in this forum, and it didn't mention that. Do you know of a guide for adjusting the yoke?
 
No, I haven't touched the yoke. I've been following the sticky in this forum, and it didn't mention that. Do you know of a guide for adjusting the yoke?

The manual for the K7000 describes it pretty well. Check out page 7.

http://www.wellsgardner.com/pdf/Service/K7000.pdf


I just finished completely converging a 25" K7191 and let me tell you that it takes a TON of patience to get the edge convergence (dynamic) set properly. It's MUCH more difficult than static convergence. You'll find that it's mostly trial and error -- there really isn't an exact science that works for every monitor. For myself, I loosened the yoke and played with it a bit, tilting and shifting it while looking at the crosshatch pattern on the monitor. Eventually (like myself) you should be able to find a "sweet spot" where 75-90% of the edges (and rest of the grid) line up properly. This is where you want to set your rubber wedges and mount them in place so the yoke rests there. Once that's done it's all fine tuning using the little strips to fix the corners and possibly some of the very fine edges. That's how it worked for me. After the static convergence (which I did first), I played with the yoke (with no wedges) until I found that 85% of the grid looked good. I set the wedges in to hold it there (and actually used a few extra from another tube, using five wedges total.) Then I made a bunch of homemade convergence strips and after a lot of patience, got the corners looking good. I also had to experiment a bit to get the very top edge to line up all the way, but got it after some time (I ended up constructing a convergence strip that used a piece of metal that was twice as long as the others, that for some reason did the trick.)

In the end, the convergence on this thing was about as good as it gets and I'm really happy with it. I'll admit that the area around the yoke looks terribly ugly as I used a ton of tape and adhesive to reinforce and hold all of the wedges and strips in place :)
 
I did that, and got it best I could. The problem is I can get the center of the screen to line up, but not the edges. Or I can do the bottom, but then the top looks awful.

Am I doing it wrong?

The photos you posted the center isn't converged, the blue is off. Before you start playing with the yoke, get the center converged.
 
The photos you posted the center isn't converged, the blue is off. Before you start playing with the yoke, get the center converged.

+1 I agree. You need to get the static convergence spot-on first. Otherwise it's pointless to attempt the dynamic convergence as you'll be running in circles.
 
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