I think he should go ahead with this mating of the tower&tree...Might just
be like "Jack&the beanstalk"...The towers great but the tree is free..Who
knows it may just grow expansion joints&he can report every QSO his antennas
are a few millimeters taller!Wow! 73 all,Jim K7RDX...
----- Original Message -----
From: <SavageBR@aol.com>
To: <w7ce@curtiss.net>; <towertalk@contesting.com>
Sent: Monday, May 07, 2007 2:12 PM
Subject: Re: [TowerTalk] Horizontal tower movement at the top
> >You have got to be kidding! April Fool's Day was over a month ago!!
>
> Bruce
>
> From: "W7CE" <w7ce@curtiss.net>
> >To: <towertalk@contesting.com>
> >Subject: [TowerTalk] Horizontal tower movement at the top
> >Date: Sun, 6 May 2007 14:20:36 -0700
> >
> >Does anyone know how much horizontal movement is considered acceptable
at
> >the top of 100' tall Rohn 25G, 45G and 65G towers? I don't see any
mention
> >of it in the Rohn catalog. I know that the tops move, I just don't know
> >how
> >much is considered normal.
> >
> >I'm considering a rather unusual tower installation at my QTH. Because
of
> >large trees that occasionally lose branches during wind storms and
property
> >line constraints, a guyed tower isn't practical. For years I've had my
3
> >element yagi on top of a 95' Doug Fir tree and it has worked well there.
I
> >watched it during our record setting wind storms last winter and the top
of
> >the tree was only moving about 6-7" (less than the diameter of my Ham IV
> >rotator). This is a big tree with a 42" diameter base and an 8"
diameter
> >stump at the 95' level where the antenna is mounted. The problem with
this
> >installation is getting up to the antenna to do maintenance, plus I'm
> >planning on replacing it with a new SteppIR as soon as I figure out how
I'm
> >going to mount it. What I'm thinking about doing is installing 100' of
> >tower as close to the tree as practical (less than 3') and attaching it
to
> >the sides of the tree with angle iron at 20' intervals. With this
> >approach,
> >I don't think the tower could ever come down unless the tree itself did
> >also, which is unlikely based on our soil type and the excellent health
of
> >the tree. I would then mount the antenna on the top of the tower. This
> >would give me a much easier way to climb up to the top. I can use 25G,
45G
> >or 65G for the installation, whichever would be best. 25G would be the
> >easiest to install because of it's weight and I suspect that it is the
best
> >choice.
> >
> >I'm looking for opinions on the viability of this solution. Will the
> >movement of the tree in the wind stress the tower too much or will it
about
> >the same amount of movement that a guyed tower would normally experience
in
> >a big wind? Opinions? Suggestions? Am I thinking a little too far
> >outside
> >the box?
> >
> >73,
> >Clay W7CE
>
>
>
>
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>
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