Hi,
It depends on how much of steel and things you have in the house,
but I should think that you can count on 25 mtrs when you are doing
your calculations, e g your antenna will be on >1 lambda on 14 MHz
and you will have a main-takeoff of approx 12 degrees and one takeoff
at 38 degrees approx about 4 dB down from mainloob.
Good luck with the construction!
73 de Owe /SM3CWE
----- Original Message -----
From: "Fabio IZ4AFW" <fabio.mantovani@inwind.it>
To: <antennaware@contesting.com>
Sent: Thursday, April 17, 2003 3:16 PM
Subject: [Antennaware] Height
> Hi all,
> I am planning to erect a 12 m tower on the roof of my house (which is
> about 13 m high HI).
> Now, when I go into antenna modeling, which height should I consider? 12
> meters or 25 meters?
> In other words, the antenna will be about 25 meters high from the (real)
> ground, but only 12 from the roof (which is not very big, about 10x10
> meters)...which height I have to consider in NEC?
> I am planning a horizontal polarized antenna (probably yagi) for HF coverage.
> Thanks, all the best
> 73
> Fabio IZ4AFW
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