How to converge a monitor

Very interesting. It was facing north west. I will make sure it is facing north next time I try. Game normally faces north but I had swiveled it out to work on it.
 
I once did a restoration which included a NOS CRT which came out fantastic. The display was beautiful.
Carefully delivered and set up the game. Applied power and the display was a rainbow of colors. I thought something must have been damaged during the transport. I pulled the game out to test further and the display was fine.
Put the game back - rainbows.....
Turns out there was a chase behind the wall where the game was and due to the amount of EM radiation coming from the bundle of wires in that area, caused the interference which prevented a game (video) from being placed there.........
 
I once did a restoration which included a NOS CRT which came out fantastic. The display was beautiful.
Carefully delivered and set up the game. Applied power and the display was a rainbow of colors. I thought something must have been damaged during the transport. I pulled the game out to test further and the display was fine.
Put the game back - rainbows.....
Turns out there was a chase behind the wall where the game was and due to the amount of EM radiation coming from the bundle of wires in that area, caused the interference which prevented a game (video) from being placed there.........

Hope you aren't planning to have kids!
 
A real noob question, so I apologize.

What do you guys use to adjust the rings? Just your fingers or do you have a special tool?

I know that the neck is where the majority of the nasties live, so I want to be very careful.
 
A real noob question, so I apologize.

What do you guys use to adjust the rings? Just your fingers or do you have a special tool?

I know that the neck is where the majority of the nasties live, so I want to be very careful.

Just keep one hand in your pocket (so to say) so in the unlikely event you get zapped, it won't go through your chest.......

Make sure someone knows that you are working on the monitor so again, in the unlikely event that you get zapped, they will know that you are missing..

But seriously, I have never been zapped while adjusting the rings, just when I inadvertently touched the back of the neck board or gotten too close to the anode cup.....
 
I have a question. What do you do when glued convergence adjustment rings break?.. Can you just use any old set from junked tubes?
 
I strip TV's that get junked for those rings and the rubber wedges and convergence strips....


Yes, every time. I've also used speakers for diagnostics / test rigs, saved degaussing coils, connectors, momentary switches, and those little twist deals for bundling wire.
 
I've got a really quick question to ask about those convergence strips as well as the angle magnet strips I see. (They are V-shaped things I see for sale online).

I've got a monitor that I "made" from a Wells Gardner 25k7191 Chassis, and a CRT tube/yoke/ring assembly I pulled from a 25" Sanyo TV. (Tube Number A63AHC26X).

Overall, the picture looks great. I have done a full cap kit, replaced the HOT, replaced the old flyback, and replaced the B+ filter cap. The only issues left with the monitor is that the image seems to shrink, then expand, when the image goes from light-to-dark, or dark-to-light. That, and the corners seem to have poor convergence along with a pincushion effect.

If I were to go and apply these convergence strips or v-magnets, would that help out with the issues I'm having? I'd really like to avoid having to pull the yoke off since I'm not certain if the yoke assembly was glued to the tube at the factory. (Since this tube is from a TV where I figure they allowed for greater "issues" figuring it'd be covered up by the bezel of the TV screen.)

I've attached some close-up images of the screen. The first being from the general center on the map screen. The second being the KO symbol in the center top. The third is the upper left hand corner where I see the most issues, and the final being the upper right hand corner which doesn't look so bad.

What's neat is that in these photos, I can see how the RGB phosphors are aligned in vertical bars in each "pixel". Perhaps I'm just being really picky as the full image when viewed from a normal distance looks incredible. I think i have to make some adjustments to the cut-offs/drives on the neckboard, but wondering if any further adjustments will be needed.
 

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Shrinking/expanding issues when the screen goes from light to dark or vice versa is a power regulation thing and completely unrelated to convergence or what those strips will fix.

Some of the shrinking/expanding is normal; look for a video of a missile command game with it's "the end" screen flashing and you'll see what I mean. :)

I have no idea of how your monitor responds to the changes in brightness; it may be okay from that perspective.

The poor convergence in the corners those strips will fix.

You need to get a cross-hatch pattern up to help see what's going on. If you don't have a TPG unit, this would be a good time to get one.
 
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Thanks guys for the responses. Yeah, I was pretty certain that magnets wouldn't help out with the shrink/expand issue. With this being a 25" tube, I figure that there are going to be some issues that I just have to live with. Knowing that I can potentially fix the one odd corner is very encouraging though.
 
Thanks guys for the responses. Yeah, I was pretty certain that magnets wouldn't help out with the shrink/expand issue. With this being a 25" tube, I figure that there are going to be some issues that I just have to live with. Knowing that I can potentially fix the one odd corner is very encouraging though.

You should take a video of the shrink/expand issue and post a youtube link for us to see. Some of it is normal; if it's at crazy levels then there may be something else going on.
 
I honestly didn't see any blooming issues in that video. If that was blooming at 36 seconds then it is reasonable or that may be by design.

There's nothing there that would concern me but I'm not familiar with that game's video. Maybe someone else with that game can chime in?
 
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I honestly didn't see any blooming issues in that video. If that was blooming at 36 seconds then it is reasonable or that may be by design.

There's nothing there that would concern me but I'm not familiar with that game's video. Maybe someone else with that game can chime in?

Yeah, I have to very sheepishly admit that I think it's just fine now. One thing I didn't do was check online for videos of this game playing on a 25" CRT. When I did, I noticed the very subtle bloom effect in all of their videos too. I guess I just have gotten so used to LCD screens that I had forgotten about that bloom effect and was being too picky. After a bunch of adjustments (moving the horizontal width coil seems to have reduced the pincushion effect quite a bit), the image looks incredible on here. I call this assembly a full success.

However, I did accidentally get bit by my monitor. :( i made a plastic coil adjustment tool out of some plastic model sprue, epoxy, and a screw wall anchor. When i went to pull it out, I was doing so at a slight angle and my hand kind of jerked up a little bit right into the coil. Holy shit that hurt. Was like i got stabbed and punched in the same spot at the same time. WOW!
 
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