Del Seay wrote:
>
> We need a bit more info. Are you using a short base in the
> concrete, or a base plate? Also - Rohn 25G is not rated
> for free standing. 30 feet of the stuff with a small tribander
> is about all you want to free stand.
> Fill us in on the details.
> de KL7HF
>
Ok, but I was trying to minimize the posting to only the essential
details. Here they are:
The Rohn 25G is rated up to 40 foot self supporting depending on wind
zone and wind loading per the Rohn catalog. The drawing for the self
supporting base specifies rebar on 12 inch centers in a 4 x 4 x 4 base
regardless of height or wind load. The base section must be either the
bottom tower section or an imbedded short base section. No other type
of base is permitted.
The tower will be 35 foot high mounting only a lightning rod, omni TV
antenna, 2M base antenna, 40M inverted V, and one end of an 80 foot
inverted L. I calculate 1.35 sf wind load--all round section. This
will comply with Rohn's 80 mph rating. K7XLC will be quick to point out
that my county is a 100 mph zone--information he kindly provided me.
However the only way those kinds of winds occur here is during the very
(so far) infrequent hurricanes.
I am not concerned about being under the rated wind speed for this
county since the property I bought came with a mobile home. Should
winds in excess of 80 mph occur, I fully expect the tower to fall on a
vacant lot. I will definitely not be anywhere near it.
73 Malcolm KR4HP
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