In a message dated 97-12-20 00:34:47 EST, k7hph@xmission.com writes:
> I have a tower question that I hope someone can help me with. I am
installing
> a ROHN 45G tower at my QTH. I am planning to use a house bracket at about 15
> feet above the ground. The bracket is bolted through the brick into the top
> 2X4 plates of the house wall where the roof trusses attach. The tower base
> section is seated in a 30X30 inch by 4 feet deep concrete base.
>
> My question is, how high can I safely go without having to use guy wires on
> the tower? The proposed antenna is a tri band yagi with a wind loading of
7.5
> sqft.
First of all, Davis County is a 70 MPH wind speed zone.
According to the Rohn pamphlet "Manufacturer's Technical Information for
Bracketed or Self Supporting Towers" (available free for an SASE to TOWER
TECH, Box 572, Woodinville, WA, 98072), 23 feet above the housebracket is good
for 13.8 sq.ft and 33 feet above the housebracket will take 5.5 sq.ft. I guess
the answer is somewhere inbetween. BTW, current Rohn specs call for two
housebrackets.
73, Steve K7LXC
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