On Apr 1, 9:29 pm, Richard Lane wrote:
JRC Seattle "reworked" my 1500 LCD display in 2005 for free upon my
complaint of fogging under humid conditions. I noticed that it again
fogged last year.
The display clamshell has two openings covered by GoreTex breather
patches and a silica gel bag taped inside. I wonder if connecting a
small computer cooling fan perhaps with a 24w heater (6 ohm resistor) to
a new pluggable opening would fix the problem?
Dick Nonsuch 26, Swoose

I would consider using a larger silica gel bag, and changing it as
soon as fogging becomes a problem. Restricting somewhat the size of
the breathers may help, but don't try to seal the case completely.

You won't be able to restrict air coming and going with barometric
changes, and the consequent influx of humidity. A small heater will
reduce the condensation effect somewhat, but you don't want to
overheat anything. A fan will introduce fresh humidity all the time,
saturating the silica gel more quickly.

A relevant question is: how much air exchange is required for cooling?

Terry K