Might be easier than my plan of installing a large fan atop the tower to
blow air DOWN to counterbalance it.... ;-)
At 09:48 AM 12-02-02, you wrote:
>If you mount the antenna upside down on the mast. Would that prevent them
>from bending up. <grin> :-0)
>----- Original Message -----
>From: "WL7M" <joe@xyz.net>
>To: <towertalk@contesting.com>
>Sent: Tuesday, February 12, 2002 11:53 AM
>Subject: Re: [TowerTalk] Antennas down FOLLOWUP
>
>
> >
> > May I second the observation about wind blowing UP the tower if you live
>on
> > a hillside. I live at 1300 feet overlooking the ocean on the gulf of
> > Alaska. We frequently observe 125 mph wind gusts from fall and winter
> > storms coming out of the gulf. My Mosley Pro57B has withstood these
>storms
> > - without damage - but it is amazing to see the elements being blown UP
> > when the winds hit. I use Philystran cables to provide extra bracing in
> > these conditions, and it pays off.
> >
> > 73,
> > Joe
> > WL7M
> >
> > > > Closer investigation this morning leads to the following: 20M boom
>broke in
> > > > UPWARDS direction! Likewise, the 15M & 10M booms were bent UP. Broken
> > > > elements appear to have been broken sideways, based on the fact that
>I
> > > > installed the clamps toward the ground. I suspect something other
>than
> > > > ordinary wind and ice loading.
> > > >
> > > This is pretty common if you live on or near sloping terrain where
>the
> > >wind is driven UP the hill and hits antennas from underneath. That's when
>120
> > >degree boom trussing is used. You've got a venturi effect going on where
>the
> > >windspeed is higher at the top of the hill than the apparent windspeed so
> > >they hardware really gets slammed in those conditions.
> > >
> > >Cheers,
> > >Steve K7LXC
> > >Tower Tech
> >
> >
> > ________________________________________________________________________
> > Where do you get ICE bandpass filters & beverage matching boxes? The
> > same place that pays for the hosting of this list: The eHam Store.
> > Order online at http://store.eham.net.
> > -----------------------------------------------------------------------
> >
> > -----
> > FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> > Submissions: towertalk@contesting.com
> > Administrative requests: towertalk-REQUEST@contesting.com
> > Problems: owner-towertalk@contesting.com
> >
> >
> >
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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