>From: Michael Tope <W4EF@pacbell.net>
To: <towertalk@contesting.com>
>Date: Sun, 2 May 1999 02:41:18 -0700
>
>Wow, Bob! With just 175 lbs of wind load you would have exceeded
>the Rohn specs for 45G, and thats neglecting the additional wind
>load on the side of the tower. This corresponds to 7 sqft of
>wind load at 80 mph. If you figure that the tower is worth
>another 2 sqft/section (this is a guess), then at 80 MPH, the
>load margin left over the antennas is only 13 lbs of wind load
>or 1/2 sqft.
Actually, the effective cross section for Rohn 45G is 3 square
feet per section. But the sections near the ground don't get as
much wind as the upper ones. So 2 feet per section might not be
a bad number to use. The point of application of this load is
probably somewhere a bit above half way up the structure.
73, Eric N7CL
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