Adjusting convergence - Videokarma.org TV - Video

lnx64 · #1 03-28-2012, 07:33 PM

So my convergence on my TV is really bad in the top left corner.

How do I adjust the convergence rings on the neck of the tube? I have never dealt with that before, ever..

http://img.photobucket.com/albums/v3...n/IMG_0226.jpg

Which btw, this is funny, cause a while ago, before I focussed the flyback, the convergence looked a bit different in other areas.

http://img.photobucket.com/albums/v3...ragon/conv.jpg

kx250rider · #2 03-29-2012, 10:57 AM

Those are tough to converge. First, degauss the tube well, as the convergence can be thrown off by magnetized mounting screws, or magnetized shadow mask that the built-in degausser can't always take care of. On those inline tubes, there are small PM magnets around the yoke, which enhance corner convergence. If you see one in the corner of the tube, behind where the misalignment is, you could try marking it with white paint, and move it a little to see if it fixes or worsens the problem. Again, it's too complicated to try to describe here, but the bottom line is that you have to fool with carefully. The fundamentals are that if there are a total of four rings, the two closest to he yoke are the purity. The rear pair are the CENTER red/green "fine" convergence, and if there is an additional pair (total of six rings), those do other funny things with the center convergence (nice technical term, LOL). The edge convergence is done ONLY by yoke tilt. You remove the rubber wedges, but to not loosen the yoke clamp. Use the wedges to tilt the front of the yoke up & down for side-to-side convergence, and side-to-side for top & bottom convergence. The most annoying thing is that moving any of the rings, can throw the purity off too.

It might also be helpful to get a copy of the Sams or the Hitachi manual for that set, and read the procedure. Sometimes they give good hints & tips more than the regular procedure.

NOTE: If the set has ever been dropped, it might have a dinged shadow mask, and that would make it impossible to get purity and convergence so good.

Charles

Username1 · #3 03-29-2012, 06:05 PM

http://www.youtube.com/watch?v=QYB1L8AIeq4

http://www.youtube.com/watch?v=yoBqm...eature=related

this one is pretty interesting about automated crt disassembly. I didn't know
the phosphorous could just be vacuumed off the surface of the glass....

http://www.youtube.com/watch?feature...&v=bT2DOwvLQoE

sampson159 · #4 03-29-2012, 06:53 PM

mark the assembly before you start.it will give you a place to revisit when you turn and twist on this for hours.you will never get convergence perfect.all you can hope for is to improve it slightly.it looks very good right now.the sylvania e chassis 19 inch portables were the only sets that i found to get perfect convergence.that was strictly my job in the shop days.no other tech wanted to do this so i got the responsibility.make your adjustments very slight and use the yoke wedges!that looks like the only adjustment you might have to make.

lnx64 · #5 03-29-2012, 07:12 PM

This is the CRT setup.. It has 6 rings.

http://img.photobucket.com/albums/v3...n/hitachi6.jpg

I was using compressed air earlier on the insides to try and clean it, and one of the tape on the yoke wires popped off. It's going to be ok, right? Or do I need to put on new tape?

miniman82 · #6 03-29-2012, 07:26 PM

Seriously? You're worried about convergence even though 99% of the screen looks perfect? Good Lord, don't ever get a roundie! There's nothing wrong with that screen shot, back away from the screen a foot or two, be happy!

lnx64 · #7 03-29-2012, 07:44 PM

Well it's not so innocent when it's showing a picture. When showing a grid it looks halfway decent. When showing a picture it becomes something else.

http://img.photobucket.com/albums/v3...n/_IGP6838.jpg

Look at the sail at the top left, the blue guns are aiming a whole centimeter off from where it should be hitting, and it's also seen in the pirate flag. Also, the top sword doesn't seem well converged either, whereas the bottom sword looks perfect.

It may be me, but I am a perfectionist.

lnx64 · #8 03-29-2012, 07:51 PM

Holy crap, I found an old picture of when this TV was last powered up before it was dismantled (and still on the solid state chassis). The picture sucked bad!!

http://blackevilweredragon.deviantar...oseup-22348328

Ok I'm fine with what it shows now.

lnx64 · #9 03-29-2012, 09:26 PM

Actually, I think this CRT may BE a delta-gun.

When I was looking at the yoke, most of the neck of the CRT is hidden, but it looks like the guns may have been in a pyramid formation.

Thing is I didn't have a clear view so I don't know for certain.

EDIT: Nah it can't be, it wouldn't make sense. It's an 80's TV, and it doesn't have the millions of controls like a normal deltagun TV does.

EDIT2: Cleaned the back of the tube, it's inline, never mind.

ChrisW6ATV · #10 03-30-2012, 02:13 AM

I think you could definitely improve the upper-left convergence with a couple of those "flag" magnets, without moving the yoke or the rings (any more than was already done). If you do not already know the procedure to use them, essentially you slide one under the edge of the yoke in various positions in the area that matches where you need improvement, then stick the magnet down when you find the right spot (watching the effects on your test pattern). Two magnets here would be better than trying to get all the change with only one; position each to improve part of the mis-converged area. It does take some practice to get it ideal. WARNING: If this is a "hot chassis" TV, use an isolation transformer! Perhaps you can get the magnets from a junked TV or computer monitor?

Username1 · #11 03-30-2012, 02:48 AM

Well I did a 25" sanyo last year with those rings and it came out almost perfect. If I knew about those little "flag magnets" it most likely would be perfect. Maybe this would be a good thing to use on round screen sets?? What the hell, my ctc5 has movable magnets all around the screen, why not try those little tape on magnets closer to the yoke?? Anyway, if you want to you can make it nearly perfect, its a small screen its possible to get it nearly perfect. All my 17" computer monitors ARE PERFECT, I'm sure you could pull it off using everything available.

old_coot88 · #12 03-30-2012, 09:14 AM

Quote:

Originally Posted by lnx64

...It may be me, but I am a perfectionist.

Perfectionism is the manic form of fuddyduddy-ism.

Just kiddin'.

kx250rider · #13 03-30-2012, 11:18 AM

Definitely not a delta gun if it has rings... All delta gun tubes have dynamic convergence boards and pots, and electromagnetic coils behind the yoke for each of the three guns' static convergence. Only one blue lateral magnet and two purity rings on the tube neck.

Nothing wrong with perfectionism... Just as long as there is patience to go along with it! (and my wife says being single would be better for perfectionists, so I'm now less of a perfectionist).

Charles

sampson159 · #14 03-30-2012, 12:02 PM

nick is right.back away and watch it!looks good.no glass tube is perfect.no monitor,tv,etc.some are very close but none are perfect.this is a common practice with beginners or perfectionists.i was like this in the shop days and spent more hours than i should have twisting and turning.run through the procedure twice and move on.i applaud your desire to make it the best you can but it looks very good as it is.very sharp picture and you should be proud to own it

lnx64 · #15 03-31-2012, 06:09 AM

Damn, so while I was moving my TV, I hadn't realized I put it right next to a magnet and now messed up the color.

I do not have a degaussing coil, but is there any quick and dirty way to try and fix it? I will get a degausing coil, but I want to watch Titanic right now and don't think the water should be green.