[TowerTalk] tool to retrieve data and build HFTA profiles

[Steve W3AHL]

Date: Mon, 05 Mar 2012 16:14:58 -0700
From: David Gilbert <xdavid at cis-broadband.com>

>HFTA will, as far as I know, work with almost any distance you choose.
>There seems to be a tacit belief that terrain points out beyond 5,000 or
>6,000 meters are not worth bothering with, but I believe that to be an
>erroneous assumption. ..snip..73,
>Dave   AB7E

HFTA is limited to a total of 150 data points in the .pro file, including 
the tower base location.  You can increase the total profile distance, but 
at the expense of also increasing the interval between sampling points along 
the profile.  What I have done is generate radials for longer distances when 
there are relevant features beyond the default 4400 meter range, then 
manually edit out the "flat" spots in the profile to fit what I feel is 
relevant into the 149 elements of the array.

This has been a purely intellectual experiment, since I never had a way to 
validate the model.  Nor is there much you can do to the antenna design or 
placement usually as a result of such distant geographical features.

Steve, W3AHL