[Elecraft] Re: [Electricity] K2/100 and Condensation

[n5ib at juno.com]

On Tue, 4 Jul 2006 10:05:47 -0400 Bill Coleman <aa4lr at arrl.net> writes:
>The problem appears to be internal condensation building up in the  
>K2. Is anyone else encountering this problem? What can be done about 
>it?


Moisture can only condense on a surface if the surface temperature is at
or below the dew point, and the dew point will be below (rarely, at) the
ambient air temperature.

So all you have to do to prevent condensation is to keep the surface ever
so slightly warmer than the ambient  air (glasses fog up when you get out
of the shower and put them on??    run hot water over them, they'll stay
clear as long as they're warmer than the bathroom air...)

In the case of radios the easiest fix, if you have the electricity to
spare in the field, is just leave the rig on. Even the QRP K2 consumes
and dissipates as heat a couple of watts (200 mA at 12 V = 2400 mW) in Rx
which should be enough to keep internals dry. Alternatively, put a couple
of those chemical hand warmers on the top cover (NOT inside the radio).
I'd put a sheet of plastic wrap or something between the rig and the
packs, because there is an oxidation reaction going on and perhaps
undesirable reaction products present. DON'T put the packs in a closed
zip-lock bag though, they need a supply of oxygen to work. 

You could tuck a couple of those silica gel desiccant bags (like those
packed with cameras, etc) inside the case. That will help to lower the
dew point of the air trapped in the case. I'd take them out right after
use though.  My K2 is a temple, and I don't put no junk in the temple. 
:^))

73
Jim N5IB
K2 #1233