On Tue, 05 Sep 2006 13:54:42 +0100, Jon D
wrote:


I am the OP.

Guess you haven't read this thread earlier this year in
sci.electronics.components

http://tinyurl.com/jftyr
"Any value in cleaning inside old monitor?"

Many were skeptical like you. But the most convincing answers came from
those who knew there was a value in doing this and I think they were the
majority.

Nope, they did what most do, made random theories about what
hypothetical advantage there might be, without any real
evidence to support the theories. Let's suppose it did help
a particular monitor, is that then evidence it is going to
help most of them? No.

Further we'd first need to know how old the monitor is (is
it even worthwhile), how much crud accumulation there was,
and a measured deviation from appropriate operational
values. Of course it's not good to let parts overheat, or
conduct along unintended paths... but what remains is
actually having that happen. A monitor so poorly designed
that it can't stand a little bit of dust may not be worth
the effort, and one buried in dust might only be a sign of
the real problem- the room needs better air cleaning
equipment, instead of individually cleaning out every part
over and over again.





EXTRACTS ...

keeping components hotter than they would be if running in
"free air" conditions.

Not only does it have the chance of getting onto circuitry, it also
changes the capacitance of the tube wall, changing the circuit for the
CRT drive elements as well.


The collection of dust, and much of that moistened at
some point makes for a leaky anode supply and feed wire at the very
least. That makes for poor or shifted focus settings, and other
problems that less than your average video afficianado won't notice.

Most folks rarely notice their focus shifting as well. One has to be
video oriented to notice such things.

Just to back the pro cleaning side, when I made my living from servicing
monitors (and before that TVs) every once in a while I'd get one on the
bench with the safety shutdown tripping because of a buildup of crap
around the anode connector or other HV parts, but then I've also had
nearly as many repairs in that people had damaged cleaning the inside
when they didn't know what they were doing!


What good does it do to only provide "extracts" that support
your biased opinion? Here's one you left out:

On 3 Apr 2006, Sam Goldwasser wrote:

If you're obsessive-compulsive and have nothing better to
do, by all
means clean the insides of your CRT equipment. But it's
probably more
likely that something will get messed accidentally, than any
significant
improvement in either performance or life span.


The high voltage area of modern CRT equipment is generally
enclosed and
or sealed with HV grease or adhesive. It's not like old
all-tube-type
TVs where everything collected an inch of dust if you turned
your back.


Yes, dust does collect. And yes in principle that may
affect something
eventually. But if there are no symptoms, leave it alone.