[TowerTalk] HFTA and diferent bands antennas

[David Gilbert]

The REAL Swiss Army knife for antenna modeling would, in my opinion, 
combine the terrain analysis of HFTA with the antenna modeling 
capability of NEC .... and do it for both transmit and receive.  I 
remain convinced that, especially for low angle signals, asymmetric 
terrain that "looks different" to an outgoing signal than it does to an 
incoming signal can cause dramatically different signal levels on the 
two ends of a QSO even if all other considerations (power level, 
antennas, noise level, ground conditions, etc) are equal.  N6BV even 
alludes to that possibility in the ARRL Antenna Book discussion of 
HFTA.  I've privately encouraged him ... begged is probably a more 
accurate description  ... to write an arrival angle version of HFTA, and 
he indicated that if he ever decided to tackle such a task it would be 
sometime in the future.  I fully understand that.  It would be a totally 
different and probably much more complex problem since the incoming 
signal wouldn't be a point source like the outgoing signal is.  Still, 
I'm desperately hoping he gives it a try some time.

And of course there's always vertical polarization .... ;)

73,
Dave   AB7E




On 4/24/2010 5:57 AM, Pete Smith wrote:
> No, it is not possible, I'm afraid.  There's not yet any svh thing as a
> Swiss Army Knife that combines the terrain capabilities of HFTA with the
> antenna modeling abilities of NEC.  Maybe some day...
>
> 73, Pete N4ZR