Greetings Topband antenna guys,
As a manufacturer of shortened vertical element receiving antennas, I have
been asked the question about sloping ground many times.
It occurred to me one day that I could use Eznec to solve the question. What I
did was to slope the elements with respect to Eznec zero elevation and made the
angle of the elements to the ground the same as if the earth under your sloping
antenna field suddenly went flat and the elements were then leaning. I lean the
verticals in Eznec to the angle offset of the questionable uneven earth.
It is not too hard to program these angles into Eznec and then when you view
the resultant plot you can turn your head or viewing angle so that the plot
zero elevation is at the slope angle or if you have any vertical elements you
simply view it at an angle where the vertical portions are vertical in your
It is a little hard to describe this but starting with a single vertical
element should help to understand the process.
What I found generally was that the patterns of the vertical antennas or
the take off angles mostly simply followed the rising ground and the pattern
stayed mostly the same up to a point where the difference in height of the
verticals was about 1/3 of the height of the element.
I suspect Eznec could easily be used on other style antennas like Beverages
or loops, etc. using my technique with Eznec.
Your results may vary . I have not tried other style antennas except
shortened verticals. I would be interested in hearing results if someone tries
Lee K7TJR OR
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