I can add a third instance. I had a KT-34XA at 130ft on a mountain ridge 1500
ft above average terrain in Maryland. After an ice
storm built up 1.5" radial ice, the 90 km/hr winds that followed destroyed the
antenna. After a couple of elements sheared off at
their boom mounts, the boom was extremely unbalanced due to the remaining ice
loads and surviving (temporarily) elements. One of
the Phillystran guys on the boom snapped, and the forces on the boom tore
through the mounting plate along the holes used by the
U-bolts.
Seeing the mounting plate (solid aluminum 3/16") ripped into three parts by ice
and wind was impressive. Also impressive were the
number of trees destroyed: over 100 within a 200m radius circle around my
house. Several wound up on the guy wires to my towers.
AB-105 tower with 1/4" EHS guys, independently anchored and terminated with
nicropress fittings, held up perfectly even after the
trees started landing on the guy wires.
-- Eric K3NA
-----Original Message-----
From: towertalk-admin@contesting.com
[mailto:towertalk-admin@contesting.com]On Behalf Of K7LXC@aol.com
Sent: 2002 March 20 Wed 09:38
To: BobK8IA@aol.com; towertalk@contesting.com
Subject: Re: [Towertalk] LXC observations
In a message dated 3/20/02 3:23:52 AM Pacific Standard Time, BobK8IA writes:
> what antennas?
A KT34XA and Force 12 420/240. Both stations are on ridgetops with lots
of wind exposure. Moral of the story? Long booms create BIG torque on the
boom-to-mast bracket.
Cheers,
Steve K7LXC
Tower Tech
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