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  #16  
Old 10-14-2019, 09:58 PM
diplocentrus diplocentrus is offline
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Originally Posted by freakaftr8 View Post
I still think your yoke position is off. Yoke slipped back and is tilted down. I'd try to press up on the bottom of the yoke and look for noticable changes.
I was finally able to get back on this and I believe you are right. I don't have a mirror that I can put in front of the tv but I did have someone watch the screen for me while I pushed up on the yoke. They reported that the bowing seemed to clear up quite well, especially around the top of the screen where it was especially bad.

Now I just need to figure out how I want to make this "adjustment" permanent. I noticed there are rubber wedges glued to the tube all around the yoke. Perhaps I can reposition some of these and adhere them in place. Not sure which adhesive would be appropriate for that though.
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  #17  
Old 10-14-2019, 10:14 PM
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Quote:
Originally Posted by diplocentrus View Post
...
Now I just need to figure out how I want to make this "adjustment" permanent. I noticed there are rubber wedges glued to the tube all around the yoke. Perhaps I can reposition some of these and adhere them in place. Not sure which adhesive would be appropriate for that though.
Maybe you don't need to reposition the weges but just push the yoke up against them?
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  #18  
Old 10-15-2019, 07:56 AM
diplocentrus diplocentrus is offline
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Originally Posted by old_tv_nut View Post
Maybe you don't need to reposition the weges but just push the yoke up against them?
I considered this but I'm not sure how it would stay in place if the unit needs to be moved. Would it fall back down and require adjustment every time? Admittedly, I'm not certain how the yoke is held in position from the rear so that could be why I'm struggling to figure out how this would work.

To clarify, when I was pushing up and slightly forward on the yoke from the bottom center, it had a decent amount of upward movement, but if I let go, it would fall all the way back down to its "original" position.

Last edited by diplocentrus; 10-15-2019 at 08:00 AM.
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  #19  
Old 10-15-2019, 11:35 AM
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freakaftr8 freakaftr8 is offline
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Loosen the lock down clamp from the rear of the yoke and push the whole thing forward to the bumper stops. There should be 3 wedges.. One on the top center and two on the bottom all spaced evenly. Once you do this, you will probably have to turn the yoke a tad to correct a tilted picture. But should fix your problem if the wedges haven't physically came unglued from the crt and moved.

Another way to do it would be to physically remove the top wedge and while pushing the yoke up from the bottom put the wedge deeper into the void there to sustain the yoke angle
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  #20  
Old 10-30-2019, 09:07 AM
diplocentrus diplocentrus is offline
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Originally Posted by freakaftr8 View Post
Loosen the lock down clamp from the rear of the yoke and push the whole thing forward to the bumper stops. There should be 3 wedges.. One on the top center and two on the bottom all spaced evenly. Once you do this, you will probably have to turn the yoke a tad to correct a tilted picture. But should fix your problem if the wedges haven't physically came unglued from the crt and moved.

Another way to do it would be to physically remove the top wedge and while pushing the yoke up from the bottom put the wedge deeper into the void there to sustain the yoke angle
This has fixed the bowing issue. I noticed that whatever adhesive was used previously to hold the wedges was not holding very well anymore. I will probably use some sort of RTV since I've noticed that seems to be what is used in other units I have gotten recently.

At this point, I'm trying to figure out if I can fix the issue in the corners. It is very noticeable that if any sort of text or high contrast images are displayed in the top and bottom left, the colors seem to be separated. According to the service manual, this can be adjusted with permalloy strips or probably whatever I can make that's similar enough.
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  #21  
Old 10-30-2019, 01:29 PM
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freakaftr8 freakaftr8 is offline
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Yes. This is what you want to do. Maybe go find a few small low power puck style magnets and attempt to position them on those areas on the back of the CRT to align the corner convergence. it's tough (and dangerous) so be careful. Try to hold the magnet with some insulated pliers and take note not to drop the magnet on the PCB or yoke windings. That would be bad. But if you can find an area that will align the corners, stick it there. Its tricky and if the magnet is too powerful, you will feel the energization of the CRT so use insulated pliers. I've done this before with mixed results.
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Last edited by freakaftr8; 10-30-2019 at 01:34 PM.
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  #22  
Old 11-02-2019, 04:59 PM
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colorfixer colorfixer is offline
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The yokes were bonded to the tube at the factory on these no?

Also I recall when these came out there was a warning about not using a degauss coil on them.
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  #23  
Old 11-03-2019, 08:28 AM
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zeno zeno is offline
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Not a bonded yoke.
You can use the magnets from a refrigerator door gasket. Also
when you junk a set save some. Move & turn the magnet while
watching then glue or tape down. Try about a half inch piece to
start. This all assumes the purity is set right. Moving the yoke
back & forth along with neck magnet setting sets it.
BTW if you mess with the neck magnets mark them FIRST !

73 Zeno
LFOD !
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