RPTV convergence or shielding issue?

Discussion in 'Displays' started by Gordon_K, Mar 10, 2005.

  1. Gordon_K

    Gordon_K Auditioning

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    Hi,
    I am a relative newbie, got all my gear based on what I have learned here, it's been great! A couple months ago, I was able to get a Panasonic 47X54 at a great price, and I've been really happy with it till a couple of days ago, when I noticed blue "outlines" around some lines on the screen, in the lower left hand corner. My L speaker (Athena B1) sits on a stand so that it's bottom is the same height as the bottom of the screen, with 6" between TV and speaker. Once I noticed the problem I moved the speaker, there was no change, but possibly the TV has aquired a charge? ON/OFF cycles over 2 days made no improvement, and I did the 16 point convergence, with only slight improvement.
    The Athenas are described as shielded, and the R speaker, tho similarly placed has caused no probs, same with the C channel, it's sitting directly on top of the set.
    What do you folks think? Could it be a shielding prob? Can I have the set degaussed? Or should I look at a service menu convergance adjustment? I think I can handle it, the instructions are good.
    Thanks for your input, I could really use it!
     
  2. Gordon_K

    Gordon_K Auditioning

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    I forgot to mention, the blue shadows appear in the lower left hand corner of the screen only. They are below the level of the speaker drivers, which makes me suspect the speakers are not the cause.
     
  3. John S

    John S Producer

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    I'd let it go for a couple of weeks with the speaker relocated. Auto degauss can be a rather odd beast when it does and doesn't do it on many displays.

    Really hard to say what it could be till it is resolved.
     
  4. Dave H

    Dave H Producer

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    I doubt it's a shielding problem. Are you sure your blue convergence just isn't off in that area? I would put up a crosshatch pattern and see what it looks like. I suggest using the service menu for convergence if you know what you are doing -- you have far more control that way.

    If not, it maybe a CRT problem. Obviously, a competent service tech would have to make the call. Be very cautious and critical.

    I bought a Sony KP-57WS520 a few months ago. I've had a problem with what looks like (colorless) interference noise waves which only appear on my screen when my set has been warmed up for at least hour or two --- only visible on very dark backgrounds because they are so faint. The last (and third) service tech I had out thinks it's a bad video circuitry part that he is going to replace tomorrow. I'm keeping my fingers crossed.
     
  5. Tim Jin

    Tim Jin Supporting Actor

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    It sounds like that you need to do a convergence in the service menu. Most likely, your guns are off, since its a brand new TV.

    I really don't think that its your speakers.
     
  6. Gordon_K

    Gordon_K Auditioning

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    Thanks for all the input! Yes, the blue convergence seems to
    be out in that corner only. I think I will try a service menu
    adjustment this weekend. So, the conv. can need adjustment in one small area only? And not a mechanical adjustment?
     
  7. Mike Gov

    Mike Gov Stunt Coordinator

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    Yes
     
  8. Jeff Gatie

    Jeff Gatie Lead Actor

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    Very possible. Most service menus offer a multi-point convergence (my Toshiba has a 64 point). You can adjust each individual point by itself, giving you much greater control over your screen than the normal single or 6 point convergence on the user menu.
     
  9. ChrisWiggles

    ChrisWiggles Producer

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    As stated, doubtful that it's a speaker interference problem. FYI, the screen itself is not where the guns are in a CRT-based RPTV, they are down at the bottom front (usually). The image is then projected and folded via mirror(s) to the screen itself which is what you see.

    You should carefully observe, via grid test patterns internal to the set, or from a test disc, and see if the blue is merely misconverged, or whether blue may also be out of focus there. This may require turning off or covering the other two guns, or looking closely at the screen to observe whether blue is merely misconverged or out of focus. If you are merely misconverged there, then tweak the convergence.

    If you are out of focus, you will need to check both optical and beam focus.
     
  10. Gordon_K

    Gordon_K Auditioning

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    Just wanted to follow up, and thank all posters! Got into the svc menu w/instructions from avsforum, took a little figuring out, and was a bit scarey, but I did it! Yup, it was just the convergance, (mostly blue) out of whack. A couple of hours later, it's much better, not gonna say perfect, but those of you who have done it will know what I mean, one can VERY picky , and spend a LOT of time. I also NOTICE more imperfections, now that I know what to look for! I think mine is better than they leave the factory now. I may tweak more later, but I am SO relieved my new tv is ok!
    Thanks again, to everyone, I have learned so much here!
     

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