>
>So, what happens to a self-supporting tower when it decides to fall? Does
>it typically stay within that 30% of height... or will my future tower hit
>my neighbor's house? (just planning my answers when the neighbors start
>asking once I do choose a tower and put it up)
Our local Emergency Management 150' self-supporting tower failed a few years
ago. Besides their 4-bay commercial VHF antenna on top, it had another 4-bay
commercial VHF at about 120' for our repeater, and a 10 el. 2m beam (and
rotor) at about 80-90', on a heavy pipe mount. Way too much stuff
side-mounted, too high. Anyway we had a storm with strong, very gusty winds.
The gusts hit the tower resonant frequency and got it swinging. It just bent
over at about the 80' point. The tip of the top antenna ended up just a few
feet above the ground (sidewalk, in this case). Fortunately, the winds blew
it toward the street, so when it swung down, it didn't hit anything. They
put up a whole new tower. Our repeater now has a Diamond instead of the
commercial antenna, and there is no beam/rotor.
Roger Grady K9OPO
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