Topband: [WARNING: A/V UNSCANNABLE]RE: Waller Flag Question

[Jim Brown]

On Mon,9/7/2015 1:05 PM, K1FZ-Bruce wrote:
> Thanks Jim,  There are new hams that do not know how horizontal 
> antennas patterns change over ground. 

Right. In general, horizontally polarized antennas only care about 
height, while vertically polarized antennas care SOME about height, but 
mostly about soil conductivity. I gave a talk at Pacificon and to a 
couple of ham clubs on this based on an extensive NEC modeling study. 
Slides are here.

http://k9yc.com/VertOrHorizontal-Slides.pdf

> On 160 meters, Usually, but nor always, higher is better up to 1/2 
> wavelength for low angle DX..
> Lousy soil, like low conductivity sand, dry desert soil, can put the 
> effective conducting ground much lower than the surface soil
>
> DX does not always come in at low angles. Antenna handbooks ARRL, and 
> Low Band DXing books are worth reading.

N6BV's Antenna Book statistical data for use with HFTA are an excellent 
resource in that regard, but I think the data for 160M is interpolated 
from data for higher frequencies. And yes, the ON4UN book is excellent 
on that topic.

73, Jim K9YC
> 73
> Bruce-K1FZ
>
> www.qsl.net/k1fz/beverage_antenna.html
>
>
>       I saw that statement as well, which noted a gain of -53 dBi. My NEC
> model, using Carlos's dimensions over lousy soil, computes -44 dBi with
> a peak at 24 degrees.
> 73, Jim K9YC
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