Stephanie,
I wonder if the Pro 95 is properly torque balanced.
On many antennas, the mechanical center of the boom,
the center of gravity, and the neutral torque point are
all in different locations. In Dave Leeson's book,
"Physical Design of Yagi Antennas" he describes a
short dummy element made from PVC which is
placed along the boom so as to balance the wind
induced torque on the antenna. This technique helps to
minimize the net torque between the antenna and the
mast. Of course if you have gusts with a lot of shear
(non-uniform winds), this won't help
The other thing you can do is to pin the mast. There
are two downsides to this. For one thing, you get
rid of your mechanical fuse and introduce the
possibility that you will find the next weakest link
in the system (the rotator perhaps). The other problem
with pinning the mast at the antenna, is that you reduce
the strength of the mast. If you aren't stacking big
antennas above the Pro 95 that will concentrate a
lot of overturning moment at the pin location, then this
shouldn't be much of a problem.
Good Luck!
Mike, W4EF................................................
----- Original Message -----
From: "Stephanie WX3K" <wx3k@ptd.net>
To: "Towertalk" <towertalk@contesting.com>
Sent: Saturday, May 25, 2002 5:37 AM
Subject: [Towertalk] Mosley Pro95
> Just an update on my Pro95.
>
> http://www.wxpage.com/tower2000.htm
>
> It rules ! With a Yaesu FT-817 I consistently work what I hear and even in
a
> small pile ups. Good reports from Japan, Antartica, Europe, Russia.
>
> Great front to back ratio and directionality is good ! The antenna tunes
all
> 5 bands very well.
>
> My only challenge at this point is to keep the antenna from moving off
axis
> on the mast during 50 MPH wind gusts.
>
> Any suggestions ????
>
>
> Stephanie R. Koles WX3K
> wx3k at arrl dot net
> http://www.qsl.net/wx3k
> http://resumes.yahoo.com/wx3k/rfengineer
>
>
>
>
>
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