Why does my TV have a green, ovoid 'stain' on the screen

[derbyram]

Why does my TV have a green, ovoid stain in the middle of the screen (particularly noticeable when the TV is showing something dark). I have tried de-gaussing it by turning the TV off for an hour but it does no good. Is my CRT b*ggered and therefore necessitating the purchase of a 36' LCD or would a de-gaussing coil solve the problem??

[sft42]

Sound to me like you have Burn In on the affected area of your CRT screen......Simply put, burn-in is damaged phosphor. The CRT (Cathode Ray Tube) is coated with an organic phosphor material hit by an electron beam each time the projector is used. When the beam hits, the phosphor glows and gives off light. The electron beam hitting the phosphor is akin to footprints across lush grass. When we walk on grass, we can look back and see images of our footprints embedded in the grass. The more the grass is walked on, the more it wears away. But if you walk on the grass and then let it rest for a while, the grass will perk back up, because it is given time to recover. The same happens to phosphor. When the light hits the phosphor, it knocks the phosphor down. Given a rest period, the phosphor perks back up and will last for years. But if we keep knocking it down, without letting it cool down, the phosphor wears out. Once the phosphor is damaged, it cannot give the same output that the other phosphor around it does. Therefore, what you see is a lesser light output in those areas and a reflection of the old image.

Unfortunately there is no way of removing this once the damage is done....sorry.

PS....a 36" LCD even if available will cost you a couple of limbs....far better to go for a 42" plasma which start at around �2500 for a good 'un.

[derbyram]

It looks like plasma it is then. Was I just nulucky to get a dodgy tube in my TV then? As I've only had it for 3 years.

[Mortartube]

I'd certainly try de-gaussing the screen with a de-gaussing coil before trying anything else as that's the cheapest option.

[sft42]

Your best bet is to try not to leave the money shot paused for so long on the porn movies :>)

No seriously, that's what causes burn....and it's why PC always have a screensaver as do most if not all DVD players...the same image being forced onto the screen after a while will ruin the phosphor....as far as I am aware if it is this there is no repair......I would personally opt of a 32" or 36" crt unless money really is no option as they have a good quality picture....cheaper Plasma screens and LCD's have time lag decode issues and various fading problems if not viewed head on.

[derbyram]

I know what yuo're saying but the missus never lets me watch 'em ;). Honestly, I can't remember a time when an image has been left on the screen long enough to cause any screen-burn. Might plump for another crt then as it may be difficult to swing a �2500 plasma TV past the fiscal committee at home, especially if the plasma doesn't perform to a better standard.

[tewsona]

a good answer, we thought this would be solved by buying a new TV in our situation but this was not the case it was infact the aerial that was casuing a green splodge on our screens