H
h
- Jan 1, 1970
- 0
As per subject. My other old CRTs go dim but all the trinitron ones go
green. Is there a simple explanation?
Cheers,
h
green. Is there a simple explanation?
Cheers,
h
As per subject. My other old CRTs go dim but all the trinitron ones go
green. Is there a simple explanation?
Dave Plowman (News) said:It's not just Trintrons - pretty well all decent CRTs do this. At one time
to get a pure red the phosphor used was less sensitive than the others, so
that gun was driven the hardest. So aged first - resulting in the green
tint.
Later CRTs used a more 'orange' red which was more efficient and didn't
exhibit this fault. But wasn't as good as the original when new.
That's for sure. Anyone remember Zenith's FTM1490?
Just stunning red.
Dave Plowman (News) said:Yes. First generation PAL sets in the UK - dating from about '70 - were
capable of superb pictures when properly set up. Then the rot set in with
PIL tubes. They may have been consistent, but never as good as a decent
shadowmask.
I work in TV production, and think the grade 1 monitors used for camera
setup use the same NTSC phosphors as all those years ago...
--
*Very funny Scotty, now beam down my clothes.
Dave Plowman [email protected] London SW
To e-mail, change noise into sound.
green does the least work.h said:As per subject. My other old CRTs go dim but all the trinitron ones go
green. Is there a simple explanation?
Cheers,
h
green does the least work.
mc said:Hmmm...
Trinitron is a single-gun tube. I would expect it to go dim rather than
having a color shift. If it goes green, maybe by losing the ability to
deflect the electron beam from stripe to stripe?
Dave said:It's not just Trintrons - pretty well all decent CRTs do this. At one time
to get a pure red the phosphor used was less sensitive than the others, so
that gun was driven the hardest. So aged first - resulting in the green
tint.
Later CRTs used a more 'orange' red which was more efficient and didn't
exhibit this fault. But wasn't as good as the original when new.
h said:As per subject. My other old CRTs go dim but all the trinitron ones go
green. Is there a simple explanation?
Cheers,
h
They haven't used the old fluorgermanate red phosphor in decades, early
60's or so? I've never actually seen a CRT that used it, everything in
my lifetime has been the newer orangish vanadate phosphor.
James Sweet said:The green phosphor tends to be the most efficient, if you've ever seen a
green fluorescent tube you'll see what I mean, the green is about 2x as
bright as the blue and many times brighter than the red.
ian said:Either that or the human eye is most sensitive at the green wavelength.
James Sweet said:It is, that's the other part of the equation, but the lumen rating is
substantially higher for the green than even for white.
Next you're going to tell us how green is brighter than white - which is
made up of red, green & blue......................
ian said:Either that or the human eye is most sensitive at the green wavelength.
Paul Hovnanian P.E. said:Or there's something about the color modulation that, with aging
components, causes the signal to drift toward green. I have an LCD (3"
screen) color TV that is about 10 years old. When driven from a
composite video input (from a DVD player) it looks fine. But the
broadcast signals are starting to look a bit green.
Hmmm, just sort of in relation to this thread: can anyone tell me if
its worth repairing my Trinitron? Model: G420S.
The red is pretty much dead now, and the blue sometimes work and
sometimes doesn't. For the most part, the green is fine. Here's a video
of it a few months ago (it would flash during warming up but would
eventually stabilize, but the video shows it's totally crapping it...
turning it OFF then ON would fix this):
http://www.samaseysan.com/temporary/Trinny_neardeathexperience.avi