I agree that the azimuth pattern will be the same, but the elevation
pattern will be quite different, and to my mind is a lot more
important. We're not doing EME here. For example, if I model against
ground, and put the antennas at heights of 50 and 100 feet, my 14 MHz
vertical pattern is very broad and clean, with no second lobe below 35
degrees or so. If I select only the lower antenna in the 50/100 stack,
the clean main lobe moves up from 12 to 20 degrees, which can be a very
useful capability late in an opening.
73, Pete N4ZR
The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at
reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000
On 8/16/2011 9:33 AM, Jay Kesterson K0GU wrote:
> The azimuth pattern will be much the same over ground. If you
> vertically stack antennas very close together you can see interaction
> between the antennas that can degrade the azimuth pattern. Although it
> might improve the elevation pattern (the useless lobes that can cause
> noise pickup from under the antenna). However if you don't have fairly
> flat ground IMO modeling over ground may or may not give you accurate
> results unless you have a program that compensates for the local terrain.
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