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Thinking about tinkering with the convergence on my nanao 2930…

I see some videos out there which provide good detail on how to apply the strips. Seems like a bit of tedious trial and error but manageable.

My question is, do you HAVE to completely take the yoke off? Should you?

I’m afraid of necking the tube lol. I’m hoping to just slide new strips in. If anyone has done this please let me know.

There are old strips there now. Are these worthless? Should I remove them and add new ones?

Any input is greatly appreciated.
 
Thinking about tinkering with the convergence on my nanao 2930…

I see some videos out there which provide good detail on how to apply the strips. Seems like a bit of tedious trial and error but manageable.

My question is, do you HAVE to completely take the yoke off? Should you?

I’m afraid of necking the tube lol. I’m hoping to just slide new strips in. If anyone has done this please let me know.

There are old strips there now. Are these worthless? Should I remove them and add new ones?

Any input is greatly appreciated.
You don't have to take the yoke off unless you're planning on replacing the magnets on the underside of the yoke.

Otherwise with convergence strips you just slide them under the edge of the yoke.
 
be forewarned If you're talking about convergence and considering moving the yoke or any of the convergence rings there is the very real possibility that after hours of adjustment you will end up with a picture that has worse convergence than when you started.

it takes a lot of patience and an understanding of what you're doing to properly converge a CRT.
 
be forewarned If you're talking about convergence and considering moving the yoke or any of the convergence rings there is the very real possibility that after hours of adjustment you will end up with a picture that has worse convergence than when you started.

it takes a lot of patience and an understanding of what you're doing to properly converge a CRT.
I guess I’m asking if i can try to get better convergence without touching the rings or yoke. Just sliding strips in as stated in my original post.
 
I guess I’m asking if i can try to get better convergence without touching the rings or yoke. Just sliding strips in as stated in my original post.
So convergence strips are for edge convergence correction. If that's what you're looking to fix, then no harm in experimenting with adding some strips.
 
One additional suggestion. Leave any original strips and just start by playing with some new/additional ones.

This is just so you can easily back to your starting state if you aren’t liking the results.
 
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So I haven’t taken monitor out yet, but in addition to the corner convergence, what pot do I adjust here? Getting a weird parallelogram shape.
 
If you don't want to touch the rings and yoke

1. I would recommend as a first step do do a cap kit. Old caps that are out of spec can cause misalignment and bleeding you don't want to fix the convergence and then do a cap kit and have it out again because it's adjusted for the old caps.

2. Degauss your screen so you're not mistaking that for convergence issues.

3. you may want to check if your yoke is lose at all. once caps are accounted for the yoke sliding back over time is the next most likely culprit so you may fix 99% of your convergence just pushing it back up, trying to align it as best you can and then tightening it back down.

4. after that you can try strips to improve things on the edges and corners.... if you can find them
 
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If you don't want to touch the rings and yoke

1. I would recommend as a first step do do a cap kit. Old caps that are out of spec can cause misalignment and bleeding you don't want to fix the convergence and then do a cap kit and have it out again because it's adjusted for the old caps.

2. Degauss your screen so you're not mistaking that for convergence issues.

3. you may want to check if your yoke is lose at all. once caps are accounted for the yoke sliding back over time is the next most likely culprit so you may fix 99% of your convergence just pushing it back up, trying to align it as best you can and then tightening it back down.

4. after that you can try strips to improve things on the edges and corners.... if you can find them
It was recapped last month.

I’ll take a look at the yoke to see if its tight once i mess w convergence Strips.

To answer my own earlier question about parallelogram… I’m guess i adjust the “para” pot on the chassis?
 
I would check the yoke before you touch the srips.

were you able to even find convergence strips? Historically they're extremely hard to come by
 
I would check the yoke before you touch the srips.

were you able to even find convergence strips? Historically they're extremely hard to come by
I haven’t looked. Probably gonna make some if I can’t find em
 
Saw a video where a guy makes them with pieces of snap off razor blades.
I've done the snap-off razor blade method before, basically take those snap off razor blades and cut up into strips a "For Sale" (or similar flexible plastic) sign from a hardware store and tape the blade sections to the ends of the strips you made (and handily you can use the blade to cut up the sign). dulling the blade and using kapton tape is recommended.

Comparing them to original strips (which I've also used) they're not as the good as the real strips. the real strips are very clean and precise in their effect on the image while the blades can move things around but leave things still a little fuzzy (but better than nothing).

I can't say I've ever used those in the eBay link. it looks like actual-ass magnets which I can't imagine would have a positive or clean effect.

for reference this is what legit ones look like: https://forums.arcade-museum.com/th...-in-canada-1000s-to-sell-now-pictures.353664/

some people have referred to the original strips as having a magnet inside but I'm fairly certain it's simply a thin piece of iron and likely gets magnetized over time by nature of being stuck to a tube.
 
Here's what I learned about convergence.

First rule : Give yourself a good documentation before preparing to spend weeks of trial and error to get something better than what you can achieve with strips.
Second rule : mark eveyry magnet and ring with a sharpie to restore original position and save 90% of time
Third rule : patience and self control.

I give you in the order of what I suggest you care about first. But I believe it's the opposite order when they did it in factory.

1. Factory magnets : There are many types. Circles glued on the tube, strips, ferrites around the yoke's plastic, ferrites taped inside, etc... in theory you should keep them in place. But practically most of them are fried, and they just make things harder when they mess instead of converging. In case you can't achieve a good enough picture and you want to be black belt in convergence, they simply need complete removal and start from scratch. Sometimes some magnets missing magnets on the yoke or on the tube itself. It gives you a picture of the complexity of all these things. Just start looking where some are missing or not but don't remove anything in the first step.

2. Corners convergence : it can be achieved with strips and small magnets on the tube, also with yoke's position but don't move it, because it's the first step when they do it in factory, so you want to move that in last resort, if it's snug don't touch it unless you want to start from scratch. It's a matter of 1 hour before achieving a good enough improvement.

3. Dynamic convergence : when you have overlapping colors on the sides it means the yoke isn't properly tilted left/right or down/up, you want to check if wedges are stil glued and yoke haven't been unscrewed by someone. If wedge is missing it means yoke has moved, just unscrew gently the yoke and try to replace one in the same position, it can be fixed in 2 hours also with a good mirror, but you would make sure the rings a tight.

4. Static convergence : it's a combination of yoke position 2 exterior sets of magnets which achieve Red/Blue alignement, and Red+Blue/Green alignement, this is also something you don't want to touch if center is perfectly white and symetrical. Mark the rings with a sharpie or you will regret not doing that.

5. Purity : If you have visible problems on raster, it means you have purity problem, either the yoke isn't in the right position, or purity magnets need tweaking, or you lost some glued magnets on the tube. Sometimes purity can change depending on the orientation of your cabinet. This can fix purity but if you have failing magnets still around it's not the right thing to do.

Lots of frustration and meditation when you want perfect geometry, the more you start again the more you understand the physics, it definitely need both understanding and lot of experience and luck. Also greediness make things more frustrating, but I believe this is how you learn. I spent a lot of time doing this, and still not happy, I just accept it when I reach my patience limit. Sometimes I take a pause and enjoy it like that before taking another breath to start messing again another inspired day. I get faster and improve on this exercise each time by the way.

But believe me you want to pick a properly converged tube from the beginning, you just have to know your limit or you will play with tweaking more than the arcades.

Also if you have pure white but still have geometry deformation, it can be the chassis.

Good luck !
 
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If you decide you’re going to screw around with the rings i.e. static convergence, put tape over the green jamma pin on your test pcb, so you remove it from your test grid. Converge the blue and red to make purple. Then remove the tape and converge the single remaining ring to the other 2 that you’ve locked in. So you’re just aligning green to the purple. Otherwise you’ll go crazy.
 
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