Can this be fixed? TV Screen Discolored

Discussion in 'Hardware Discussion & Support' started by Dyre Straits, Mar 23, 2007.

  1. Dyre Straits

    Dyre Straits 9 Count 'em, 9 Grandkids!

    This image has been enhanced to show the discoloration of the screen. I took the whole thing a part the other night and moved the speaker completely out of the way by disconnecting it. It made no difference on the TV screen.

    This is a 32 in RCA ColorTrak Plus that I've had probably about 8-9 years. But, I haven't been the one using it. Only after someone gave my son a widescreen projector TV did I decide to move this one into my office.

    Can this image be degaussed. Notice not only the discoloration in the lower right corner, but there's some in the upper left, too.

    It really is annoying. I was hoping to get used to playing some games on the TV in an effort to make some adjustments to playing console games. So far, I'm not having much luck.


    [​IMG]
  2. ChaosMinionX

    ChaosMinionX USB 3 dot oh


    Did that TV sit at an angle for an extended period of time? or did it have unshielded speakers?
  3. Dyre Straits

    Dyre Straits 9 Count 'em, 9 Grandkids!

    I'm not aware of whether it had any external speakers near it or not. If it did, there would likely have been one on the left side, too. The speakers in the TV are both in those lower corners.
    Unshielded speakers is exactly what crossed my mind and is why I took the back cover off and disconnected the speaker entirely and moved it out of the way. It made no difference.

    It really does stand out a lot since it's such a large area that's affected.
  4. Tipstaff

    Tipstaff Well-Known Member

    Definatly looks like magnetic distortion to me. If the TVs internal degaussing coil isn't working (or in this case it probably doesn't have one) then I'd normally suggest grabbing a degaussing coil (you can rent them.. although finding a place that has them might be harder than it was as easy to suggest it), wrapping it around the TV, and blasting it a couple times, but there are some more... unorthodox methods you can try first:

    Degauss using a CRT monitor. Try placing a CRT monitor face to face with the TV dead center to the spot that is discolored (you may need to move the monitor around to get the best effect, so try different spots). Then degauss the monitor a couple times. If it doesn't work try leaving the monitor and the TV on a for a bit, then degauss again. It sounds crazy, but believe me, I have seen this work. Oh.. and don't try using a dinky 13" CRT monitor for this. You need something a little more bulky, like a 19" or 20" CRT (or a 17" from a good manufacturer like Viewsonic or NEC). The reason is that that bigger they are, the more powerful the internal degauss coil needs to be. Also, due to it's size, it will have a greater chance to produce a degauss effect large enough to encompass that spot on the TV.

    Drill it. Seriously. Strap a couple strong magnets (something stronger than what you suspect screwed up the monitor/TV.. preferably something with a strong reversed pole to each other) to the end of a drill bit on a high powered drill, rev it up, bring it close to the discolored spot, and start waving back and forth. At first I thought this was pure nonsense, but then I saw the same thing mentioned on THIS page, and decided to try it out. Hell, I had nothing to lose by trying, right? Sure enough.. it does work. As someone mentioned on that page it took a few passes to get it work.
    Last edited: Mar 23, 2007
  5. Dyre Straits

    Dyre Straits 9 Count 'em, 9 Grandkids!

    Tipstaff:

    I had read something about the drill/magnet thingy elsewhere. Are we talking bar magnets held to a bit by duct tape? If so, does it make any difference if the N or S pole is pointed to the TV?
  6. Judas

    Judas Obvious Closet Brony Pony

    Heres a neato tip.. that while may NOT solve the problem, may give it a good start.


    Put the TV somewhere that you can easily rotate and a tilted without to much issue. Now if you tilt it, you'll need to have it sit there for a length of time and shouldn't be moving even at the slightest.. Also MAKE sure the tv screen is facing AT BEST perfectly north OR south before starting this (not only is this the best way to start, but it also gives you referrence to a starting point. )

    Heres what you can try to do.

    Turn the tv on and pick a channel (if possible) which you can clearly see the distortions. Now slowly rotate or/and tilt the TV to see if the distortion gets slightly worse, or better, if it gets worse, go the opposite way. If there is no effect at all, the games up, this trick won't work, IF there is an improvement, even a little. try to get the best improvement spot possible, then leave it at that point, turn the tv off, and unplug it. Let it sit for about 5 minutes roughly.

    After 5 minutes is up, and still unplugged, set the tv back to it's orginal starting position (facing north or south, which one you had picked BEFORE). Plug in the tv and fire it up, check to see if the distortion has come back as bad as it was, OR if the distortion is as you had last seen it. If it's improved, repeat this cycle as many times as you can or get tired of doing.

    It's a fairly time consuming method, but it has worked on quite a few tv's. This trick is best suited for TVs that were fine before, and then setup later, OR moved while it was on.

    Short of that, a Full Manual Degaus (with the proper tool) will take a split second at no real cost if you can find a decent place to do it. Or other methods like tipstaff mentioned...
  7. Tipstaff

    Tipstaff Well-Known Member

    In my case I used a couple round neodymium speaker magnets (great for magnetizing screwdrivers). Simply attached them to the drill using their own magnetics, one on each side, and as close to the tip of the drill, and then wrap some duct tape around them for security (otherwise when the drill speeds up they'll ..um.. fly off... fun to watch actually... until one hits you).
  8. Matth

    Matth Flash Banner Hater

    3 possible issues:

    1. Magnetization of the shadowmask (fixable by degaussing)
    2. Magnetic distortion of the shadowmask (from higher power/closer magnets than above, or by hamfisted degauss attempts using excessive power) - NOT FIXABLE
    3. Loss or slippage of convergence / purity magnets (actaully, not sure if inline tubes still use these)

    If there is a built-in degauss, it will normally reduce fields a little at each hit, taking about 5 minutes to reset before it will activate again (also applies if using the "screen to screen" method to borrow another monitor/TV's degauss.

    I'd say the corner to corner effect may be field at the worst corner creating an opposing pole at the other corner.

    Consider all possible ac field emitters, I'd guess a cordless (and contactless) toothbrush charger radiates a considerable field, as would the pad for a battery-less mouse. Maybe a head demagnetizing wand.
  9. Zelig

    Zelig New Member

    In an aperture grill monitor, will "shadow mask" simply be replaced by "aperture grill" in these cases?
  10. swimtech

    swimtech New Member

    Hey Dyre,
    The effect there looks pretty dire :( ...

    You could probably take it to a TV shop and have them try a degaussing coil on it.

    Other than that, it would likely take a manual adjustment of the position of the deflection coil and/or the purity-convergence magnet rings inside the unit mounted on the neck of the tube to get rid of that purity problem. The procedure for that is not complicated really, but requires care and caution as it involves moving the assemblies by hand while the set is running and hooked up to a signal generator.

    If that doesn't take care of the problem, then the shadow mask (it is not an aperture grill type) has become detached from the face of the tube, and as Matth says, that is not fixable.
  11. Dyre Straits

    Dyre Straits 9 Count 'em, 9 Grandkids!

    Thanks for all the replies so far. Due to my work schedule...and the size of this TV...I haven't had time to try any of the suggestions yet. I'll likely see if I can pick up a degaussing tool to see if the problem is permanent or fixable. If it's permanent, I'm definitely getting rid of this TV ASAP. It's just too annoying under too many circumstances.

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