Colour Patches

Hi guys and gals, its nice to join you.

I've been reading around the last couple of days and you all seem like a friendly knowledgable lot so I was hoping you could help me with a problem that has recently surfaced on my tely.

I have a 100hz Thomson Scenium (sorry no idea as to the model designation) 28" WS as part of my setup which I am very pleased with. Picture quality is excellent, Nicam and VDoldy sound is fine, but I use a Denon 1601 amp and Mission/Celestion speakers for the movies from my Proline DVD Player and Sharp VCR.

Anyway back to the point. For the last week or so I have noticed a blue smudge appearing in the top left corner of the screen. If I switch the TV off at the set and leave it for a bit, when I switch it on again the smudge is gone or so faint as to be invisible, but it reappears after about an hour and a half of viewing, regardless of the source.

Can anyone advise me as to what it is and if I can fix it? It is driving me nuts!

Cheers, Dave

[Kevo]

Do you have anything near or on top of the TV that could be causing interference, like an ext speaker for instance?

I have the Celestion 35 Centre speaker on the top of the tv, but according to the manual this is shielded so shouldn't cause a problem. The fronts are Mission 702e floorstanders and are both 0.5m from the nearest point of the set. The manual for these advises to mount them 0.45m or more from the set so this should be fine as well. I have my VCR and NTL box on low racks virtually floor level between the tv and left speaker (same side as the smudge) and the amp and DVD below the tv in the Thomson supplied cabinet.

Hence my confusion, I could understand if the speaker was too close or if the smudge was constant, but as turning it off removes the smudge and it slowly returns I am perplexed. The set is about 9months old so still within warranty.

Any ideas?

I don't own this model of tv but perhaps the most logical thing to do is try moving the speakers well away fom the set temporarily (for a week perhaps) to see if the stain still persists. That way you can be sure that the speakers are causing the prob.
But the type of stain you are describing is similar to the tube burning (I don't know its technical name). If the contrast/brightness is very high and a pure white image is shown then a 'shadow patch' may appear on the screen. Usually this diminishes when a darker image is viewed. The instruction manual should mention this usually with regard to using computer games with the tv. If this is the case then try reducing the contrast.

It's just an idea.

Thanks for that, I'll try moving the speakers well away for a bit and see what happens. Unfortunately I'm a bit restricted with the fronts as they are only 20cm from the side walls (long narrow room). As for the computer games, since I have had the tv my dad has nicked the playstation and has it at his house so it's probably not that! It was definately at it's worst during Shackleton last week, all the white really picked it out. It is only on light images that it is noticeable, with any colouring the blue is invisible, except for the lovely new Sky orange screen where it shows as a darker orange patch.

Dave
I am not familiar with the Celestion centre speaker but I do know that some speakers have their grills fixed by very small magnets. I am also aware that some TV's are more susceptable to this problem than others.
Try removing the centre speaker for a while - just an idea

[Garrett]

I have even heard of TV’s picking magnetic interference from metal structures in the walls.
Also my parents got blue stain in every corner on their old set ( I think it was picking up the magnetic field from its own speakers (Sony)), they cured it by switching of at the mains each night.
If it is you speakers causing the trouble, can you move them forwards of the screen if you are at the max sideways.

Ruby quartz shades.

Thanks for the help guys.

I moved all the speakers up the other end of the room to ensure there was no interference from them and as I removed the centre speaker there was a minor but noticable difference. I then spent 2 hours running through the degaussing sequence a few times and after each cool down I switched off at the plug for 15mins.

The picture is now back to normal. Left it on for a few hours in the evening and no return of the smudge. Woohoo!

I think I shall mount the front speakers forward as suggested but what do you suggest I do with the centre speaker? On the floor in front of the TV or in the cabinet where the Amp currently is?

Any possibility of mounting the centre speaker to the rear of the TV. It needs to be away from the screen but off the floor for good dispersal of the sound.

how do you mean, like on a stand mounted on the top of the tube?

Not sure of the design of your TV but temporarily stand speaker on the cabinet to the rear of the screen - at least that will prove whether the position is OK. As for a permanent solution maybe a stand, wall mount or any other idea. Can it be mounted in the TV cabinet or is that too close to the tube? These are only ideas, if anyone has a better one then feel free to suggest it
I wouldnt suggest putting it on the floor as the dispersal of sound will not be correct.
Best of luck