[TowerTalk] wind load vs Rohn specs

[Kurt Andress]

Steve wrote:

> Hi Kurt, I have a pretty good understanding of the tower specifications in respect
> to wind load. My question is, the typical wind load listed by the antenna
> manufactures is the effective projected area or is there a judge factor placed on
> the epa to come up with the wind load rating? Thank for your input, it's been very
> informative.
>
> tu es 73 Steve

Hi Steve,

Hygain provides projected areas and the old combined area x  .67 to compare with the
competetition.  Force 12 explains in the catalogue they have taken the larger
projected area of either the elements or the boom and reduced it by .67, so it is an
effective area according to EIA-222-C. So it will be a lower number than the old
combined and reduced areas. Multiply it x 1.5 to get the max projected area and
compare that to the larger Hygain projected area and you have all apples done the
current way, and the number to use on your tower.


Don't know what the rest are doing, they don't say!
A guess would be that they are using the old combined antenna area and multiplying it
by .67.

The best way to know is to ask them! If they confirm it, let'em know that's not what
you need.


--
73, Kurt, K7NV



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