No joke! It was a serious question and I was hoping for some serious answers.
Specifically, how much movement is normal for the top of a 100' Rohn 25G tower.
----- Original Message -----
To: email@example.com ; firstname.lastname@example.org
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!!
From: "W7CE" <email@example.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
>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
>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
>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
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