From:
Fred Hopengarten K1VR 781/259-0088
Six Willarch Road
Lincoln, MA 01773-5105
permanent e-mail address: fhopengarten@mba1972.hbs.edu
SUMMARY
From: k1vr@juno.com (Fred Hopengarten)
Subject: [TowerTalk] Visible Material
A Question of Measurement
In the March 1997 issue of QST, I wrote a column entitled: "Talking
to the Town." I solicit contributions from this reflector, however, on
how
to present the issue of size to a town body.
Rohn 25 is an antenna support structure 12 inches in face
width. Rohn 45 is 18 inches in face width. Yet each is built with
a lattice structure. As a Volunteer Counsel, I think I'd like to
make those measurements seem even smaller, if the right phrasing can
be created. Lattice towers have a lot of open air, so I'm thinking
it ought to be possible to craft sentences such as:
While carrying a 12 inch face, for each square foot of structure,
only ____ square inches of that square foot is steel. The rest is
clear air.
OR
For each square foot of this structure's face, only ___ % is solid
surface, dramatically reducing visibility.
I would welcome your suggestions, calculations, or measurements, for
Rohn and other towers..
Fred Hopengarten, K1VR
Six Willarch Road * Lincoln, MA 01773-5105 * 617/259-0088
e-mail: fhopengarten@mba1972.hbs.edu
==================================================================
From: Chad Kurszewski WE9V <kurscj@oampc12.csg.mot.com>
>From memory and may not be 100% correct:
Rohn 25 legs = 1.25" dia
Rohn 25 crossbraces = 5/16" dia
Considering 3 legs, and 3 crossbraces for a cross-section (not 100%
correct), the area is 4.6875 square inches.
And, if viewed from the correct angle, one leg and one brace is hidden,
for only a 3.125" obstruction!
---
Chad Kurszewski, WE9V e-mail: Chad_Kurszewski@csg.mot.com
The Official "Sultans of Shwing" Web Site: http://www.QTH.com/sos
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