I've never seen a crt with a line of dead anything ! If its a dead
straight vertical line then its unlikely to be the crt. Possibly some
artifact of the video feed... maybe ?
It's a Trinitron tube. This type of CRT doesn't use a shadow mask.
Instead, it uses a shadow grid - a bunch of very fine parallel
vertical wires, stretched from top to bottom.
An occasional fault in a Trinotron is for one of the shadow wires to
end up out of position. If I recall properly, this can happen if
somebody uses an external degausser - the magnetic field can shove one
wire across the one next to it. This will cause a subtle vertical
stripe to appear on the screen.,. looks rather like a row of dead
pixels.
I think there's a Field Engineering Repair procedure for this...
rapping sideways on the case, with just the right amount of force, to
jar the stuck wires apart and allow the displaced one to snap back to
its correct position. I don't know how much force is required.
One can sometimes see this effect even on a perfectly good
Trinotron tube... I think that in some models there are vertical
reinforcing rods in the grid assembly which can produce a shadow on
the tube.
[/QUOTE]
Dave: Thanks for those notes. I wasn't aware of the vertical wire grid
in a Trinitron tube. I knew about the two horizontal ones. I can
actually see those in my screen.
