Posted by Bob Myers on 11/06/07 19:20

"Igor" <donotreply@nospam.com> wrote in message
news:22e1j3dlo839fk9de6c5padp9gq1jq1o3h@4ax.com...
> I have no idea what the life expectancy is for a CRT monitor, but I
> know they don't last forever, and I imagine there are only so many
> times you can send them off somewhere to be refurbished before it's
> time to kick them to the curb.

The shortest-lived component in terms of useful service
life is, of course, the tube itself. CRT failures are most
typically the result of cathode and phosphor aging, so
rather than quote a time to absolute failure CRT lifetimes
are most often given in terms of "mean time to half
(initial) brightness." Typical MTHB numbers, unless
you've got a tube with a fancier cathode design (VERY
rare in monitors) are around 15K hours or so, depending
on the usage profile. The rest of the monitor shows reliability
numbers as would be expected for relatively high-voltage
analog electronics; something in the range of 20K-30K hours
for the MTBF used to be typical, although I believe CRT
monitor overall quality/reliability numbers have been
dropping recently as the technology became more and
more relegated to the "economy" end of the market.
Realistically, I would estimate that the average CRT
monitor, in typical use, would have a service life of
something around 5 years, but that's off the top of my
head - it's been a while since I needed to track CRT fail
rates as part of my everyday work.

And realistically, a CRT monitor cannot be "refurbished"
without replacement of the tube. CRT "rejuvenation" procedures
have been widely discussed, but all they really do is to
expose a bit more of a "clean" cathode emitting surface
which will boost the output for a while. But at that point,
most of the cathode material is already long gone, and all
you're really doing is hastening the end of life.

Bob M.

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