[TowerTalk] HF2V Elevated or On Ground

[Jim Brown]

On 11/13/2013 12:48 PM, James Setzler wrote:
> Anyone else have experience with the HF2V mounted up using elevated radials
> versus ground mounted with limited on-ground radials.

Over the summer, I did extensive modeling (NEC) of vertical quarter-wave 
and vertical dipole antennas, comparing performance on the ground and at 
typical roof heights. A report on that work is on my website in the form 
of a pdf of the Power Point for a presentation I did at Pacificon last 
month.

http://k9yc.com/publish.htm

The executive summary -- for all vertical antenna types and almost all 
soil quality, roof mounting outperforms ground mounting. The advantage 
of roof mounting is greatest for the poorest soil, varying from as much 
as 8 dB for very poor soil to a dB or so for extremely good soil.

I did one series of signal strength measurements on a real antenna -- a 
20M vertical dipole that was first measured with the base at ground 
level, then at 10 ft, 20 ft, 30 ft, and 40 ft, and finally with the 
center on the ground and the bottom half horizontal (at W6GJB).  The 
difference between 0 ft and 40 ft was 10 dB over a 5 mile path (to a 
vertical antenna at my QTH). The soil at his QTH is quite poor.

73, Jim K9YC