Line across CRT

[Craig234]

I have a recently purchased Sony FW900 CRT.

There is a one-pixel high horizontal line across the screen.

It doesn't affect gaming really, but it's a little annoying for things like message boards. It's like a tiny thread, just smaller than the border graphics in this message box.

While it's very small, you know how you tend to notice and stare, it's a distraction.

I don't support there's anything that can be done to fix it?

 

[xtknight]

That is an alignment/damper line which is inherent on Trinitron (aperture grille) CRTs. A 24" should have two or three. Most of the time they are very hard to notice and if you just use it for awhile it won't be an annoyance at all.

And, no, there is little to nothing you can do about it. Perhaps adjusting the brightness, contrast, or gamma would make it blend in more.

 

[CP5670]

It sounds like you're seeing one of the grill stabilizing wires. All aperture grill monitors have at least one of them; most have two. They are a little annoying, but you get used to them after a week or two, and AG CRT monitors carry numerous other advantages over other types of displays.

 

[Mem]

Yep its normal.

An alternative way to accomplish the same task is taken by some CRTs. Instead of using a shadow mask they use what is called an aperture grill. Instead of a metal mesh, this type of tube uses many hundreds of fine metal strips that run vertically from the top of the screen surface to the bottom. These strips perform the same function as the shadow mask--they force the electron beam to illuminate only the correct parts of the screen. The most common type of tube using this design is Sony's popular Trinitron, which is used in many brands of monitors.

Compared to a shadow mask design, aperture grill CRTs have some advantages and one significant disadvantage. One advantage is that they allow more of the electron beam to pass through to the phosphor; this results in what many consider to be a brighter overall picture. Some also say that the picture on this type of monitor is sharper. Finally, because the strips are run straight from the top of the monitor to the bottom, this type of tube is flat vertically; it curves outward as you go from left to middle to right, but not as you go from top to middle to bottom. Most people find that this reduces glare and results in a more pleasant and less distorted image.

The major disadvantage of using the aperture grill is that a bunch of thin metal strips don't have the same physical stability as a metal sheet with holes in it (the shadow mask). This means that the metal strips can tend to vibrate. To correct this problem, one, two or three thin stabilizing wires are run horizontally across the screen--more are used for larger screens. These eliminate any problems with the metal strips moving around, however they cause an unfortunate side-effect: the appearance of very faint lines where the stabilizing wires are.

These lines are extremely faint and not usually noticeable unless you are looking for them, but cause a lot of controversy because many people don't understand what they are. Invariably, they display a full screen of white pixels one day and notice the line, and then think there is something wrong with their monitor. This is in fact normal for this type of display; it does bother some people and these should not use a CRT that uses an aperture grill.

 

[tersome]

I'm pretty sure that's normal - it's a trinitron thing. Those lines might be from the damper on the aperture grill.

Most people just get used to it I guess.

 

[IlllI]

maybe this ?
i remember some old crts used to have two thing horizontal lines on the screen. maybe it uses the same kind of technology in the FW900 ?


edit: i type too slow

 

[Craig234]

Thanks a lot for the replies.