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Re: wx proof

>From: Bob V Johnson <w7lrd@juno.com>

>I am a day or two from getting on AO-40.  My rx system works very well. 
>A smaller primestar dish with a 3731aa down converter.  How concerned
>should I be about weather proofing the down converter, and the helix
>feed?  I live near Seattle, it rains a lot here.  I saw G6lvb' web site
>complete with a plastic bag over the converter.  My 70CM side is not
>quite ready.  I look foward to talking to many of you.  Be gentle with
>me, I'm new to AO-40.
>Seattle, Wa.


My experience with a unprotected helix feed was that rain will detune the
helix plus you get signficant "rain noise" when it is raining.  So some
sort of radome or RF transparent cover is advisable.  In Seattle you want a
wx cover for the electronics.  Don't hermetically seal up things,
though...leave a drain hole in the bottom of the enclosure so condensation
can drip out!  I found some inexpensive plastic chassis boxes at Radio
Shack for my MKU-232A preamp...I sealed the seam and around the coax
connector.  My Drakes are built for outside use so nothing done there, but
sealing the coax connections (I placed the F-connectors pointing down so
moisture would not enter there.  We get the same rainfall as Bellingham, WA
(32-in/year) plus cold arctic winter temps famous for causing condensation


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