Jim
The concept of horizontal dipole is just a name for a wire parallel to the
ground. If you change the description from TOTAL Field on EZENEC and use
Horizontal and Vertical field your results won't be the same. On low bands
Total Field is just one dimension. Horizontal and Vertical makes all the
difference in propagation and signal to noise ratio.
JC
N4IS
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Jim Brown
Sent: Monday, September 07, 2015 5:32 PM
To: topband@contesting.com
Subject: Re: Topband: [WARNING: A/V UNSCANNABLE]RE: Waller Flag Question
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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