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Re: Wet Trees?



Tony,
I think that determining the attenuation of foliage is folly. There are so
many different types of leaves, different square areas, different moisture
levels, and different densities that defy quanitization. I do ATV and
general opinions of others on ATV is if there are trees you are dead duck as
far as sending and receiving signals above 2 M  Removing some bushes in my
front yard rased the 10,368.330 beacon from an S1 to 10dB over S9

Art,KC6UQH
----- Original Message -----
From: "KT2Q" <dxdx@optonline.net>
To: <amsat-bb@AMSAT.Org>
Sent: Thursday, January 27, 2005 8:55 PM
Subject: Re: [amsat-bb] Wet Trees?


> Emily,
>
> I asked a similar question a while back about AO-40's S-mode downlink. The
> answer I got was that most satellite communications text books state that
> attenuation at 2.4Ghz was about 3db per meter of foliage. Assuming that
> foliage attenuation varies with the square of the frequency, there should
be
> much less atennuation at 435mHz than 3db per meter.
>
> I'm sure Dominico ( I8CVS) would have the answer to this one.
>
> 73, Tony KT2Q
>
>
>
> > On Thu, 27 Jan 2005 08:01:51 -0800, Emily Clarke <w0eec@amsat.org>
wrote:
> >> In the past few months I've noticed that there are days when I just
can't
> >> work SO-50 below 12 degrees
>
> >> After testing power out/VSWR and passing the test, the next thing that
> >> came
> >> to mind is that the wet trees, mostly thick pines and laurels which
still
> >> have their leaves, are attenuating the signal more than when they are
> >> dry.  Does that seem possible?
> >>
> >> 73,
> >>
> >> Emily
> ----
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