Joe L Blackwell wrote:
>
> Say, Kurt, is there someway you could maybe condense your response,
> make it a little more understandable to the masses out here?
> Maybe get right to the point, as it were?
> de Joe AA4NN
>
Hi Joe,
Ok, here's right to the point.
We are using invalid antenna area figures to load our towers and most
folks don't even know it!
Tower specifications are looking for one value (the apple) and most
antenna areas we are using are a different value (the orange).
Here's just one example:
One old, widely accepted practice allowed for the antenna "projected
area" to be multiplied by .67 to produce the "effective area." Now, to
apply this antenna area to a current Rohn design, we need to multiply it
by 1.5 to get back to the "projected area" that the Rohn design is
expecting. If we don't do this, and fully load the tower to the stated
max allowable area, we end up with a tower that actually has 50% more
antenna load on it than we think.
There's even more potential "hair in the butter", but were being
concise, not thorough.
I'm really sure that a lot of folks are unknowingly overloading their
towers, with antenna areas that are incorrect for the expected purpose.
That's why it bothers me!
Explaining and understanding the problem defies concise.
The point is, we are getting and using antenna area figures that that
don't work with our tower designs.
Was that any better?
--
73, Kurt
K7NV "That's K7 "Nevada" (ex - NI6W)
YagiStress - The Ultimate Software for Yagi Mechanical Design
Visit http://www.freeyellow.com/members3/yagistress/
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