[R-390] R-392

[Roy Morgan]

At 08:36 PM 10/10/2005, John Bunting wrote
:... have four packages of Silica-Gel, two cloth ones with 15 grams each 
and two larger paper ones with about one ounce each.

John,

(This is based on limited experience with silica gel):

A dried out pack of silica gel will absorb maybe one third it's weight in 
water.  It's unlikely that an R-392 contains more than an ounce or two of 
water in the air inside, even if warm and saturated.  But:

1) If you dry out your silaca gel packs, weight them, put them back in the 
radio and the weight goes up by maybe a third or half, then they can't glom 
any more water.  ("Glom" is a technical term used by a jeweler while we 
were an buying engagement ring about a year ago: "Don't glom the stone!" I 
was sternly advised.)

2) If the radio shows condensation inside the window, especially upon 
cooling, then there's moisture inside there.  Good idea to get it out. 
Though I don't own an R-392 (yet), here is my suggested procedure:
  - wait till a dry day arrives
  - Run the radio till quite warm, and crack the case so it ventilates.
  - close the case nicely to keep the dry air inside.

3) If (when) I have an R-392, I will tuck inside there somewhere an 8-ounce 
pack of silica gel from among the few I've collected. (They were found in 
helicopter transmission and engine packing cans during my time in the 
Navy.)  I'm assuming that room for such a pack can be found in there 
somewhere.  About the size of a large pack of M and M's.

4) To de-water, place in any oven, kitchen- or toaster- at 220 to 250 (low 
to medium "WARM" on the dial) for a couple hours.. then allow to cool off 
with the oven. If you weigh your packs before and after de-watering, you 
will know how much water they can absorb.

>  I've heard about putting them in a cookie tin or something and low 
> temperature baking them for ??

The cookie tin won't keep in much moisture with heat but I would not put 
them in any tin.. just in the oven. You are baking the water OUT, not 
trying to keep it in.  Plastic bags, maybe two layers, server as storage 
after drying.

Roy

- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Cell 301-928-7794
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