"Cydrome Leader" wrote in message
...
Ian Field wrote:


"Cydrome Leader" wrote in message
...
Ian Field wrote:


"N_Cook" wrote in message
...
On 02/03/2014 15:41, Rich Webb wrote:
On Sun, 02 Mar 2014 12:55:11 +0000, N_Cook wrote:

Cause and any amelioration, short of draining the liquid and
starting
again (for elfin safety in nothing else), and of course unobtanium
replacement displays

Where I used to work a batch of early large LCD display Philips DVM
meters for the engineers.
Every now and then , despite warning labels, someone would leave one
in
direct sunlight (UK version)

heh

for a while and the display would become
next to useless, permanently.
Presumably the LC migrates out of its assigned wells and does not go
back in them. Anyone know of a localised heat/cold/pressure
treatment
or
something like that ,at least, won't make matters worse , and may
actually improve the splodge a bit?

That's been a problem with older LCD displays on Fluke DMMs as well.
My old 8050A is starting to exhibit those symptoms, despite having
been indoors all of its life.

It's ameliorated somewhat on mine when the display is energized for a
few hours; the dark areas retreat and become somewhat dimmer. Not a
permanent solution, but you might try that. Hook one up to an
external
supply (they are battery powered?) and let it run over a weekend to
see if there's any improvement.

There are several hacks around the 'net where folks have replaced the
LCD module with a bank of 7-segment LEDs. What I'll probably try is
to
fit an EADog 1x8 LCD module in place of the original, with a small
micro to handle the display initialization and character translation.
The EADog is 55 x 31 x 2 mm, a good fit for the 8050A.


This display is actually on a CD unit. Its not been used for some time
so
may be what you say. Its also on the lower part of the display,
perhaps
turning the CD upside down,

Once I repaired TVs for a back street bodger - a CTV came in with a
rainbow
pattern on the picture and no amount of degaussing did any good. For
some
reason I up-ended the TV, the picture improved a lot, so I turned it
completely upside down and the picture was perfect.

We took the CRT out and put it back upside down, then slackend the yoke
clamp and rotated that 180 deg, the purity rings needed a tweak but all
was
well - so we wedged a lino tile between the anode cap and PCB to stop
it
cracking over, and cased it up.

That reminds me of when people actually rebuilt or replaced picture
tubes.
Any good stories of tubes imploding?

I always made the scrap ones safe by knocking the neck off.

I'm aware of one guy that broke a neck off, by accident at a shop, but
nothing past that.

I've got to check you tube for vidoes of people removing the steel band
around a CRT. Not sure how you'd even weasel under one to cut it off, and
from a safe distance, but somebody somewhere has to have tried.

Years ago I used to visit the local tip to pick up TVs to refurbish, once I
found a set that I only wanted the PCB from, so the quickest way to remove
the wooden cabinet and all the other unwanted stuff was with my steel toecap
boot - during this procedure, the faceplate fell off the CRT - its literally
only glued on!

On another occasion someone I knew was minding the site while the regular
bloke was away, I persuaded him to slowly advance the hydraulic ram in the
compactor while I nipped a CRT diagonally across 2 corners between the ram
and the opening in the container. Once I was safely out of the chute we
switched the ram back on, the hydraulics did a great deal of heaving and
grunting - meanwhile some bloke had gone up the steps to tip his rubbish,
suddenly there was an almighty bang, the ground shook and the bloke was
enveloped by a silver blizzard that used to be the metalisation inside the
tube.

I've seen photos online of the aftermath of an implosion on a CRT production
line - apparently its possible for one imploding CRT to set off a chain
reaction that destroys quite a few.