Many hams --including myself-- have had very good results using only a few
elevated radials.
This question contains an answer with a NEC 4.2 plot comparing the
efficiency of earth vs. elevated radials:
https://ham.stackexchange.com/questions/9823/how-does-the-performance-of-elevated-radials-differ-from-that-of-buried-radials
From the publications of N6LF (Dr. Rudy Severns) and others, they can be
almost the same. Please scroll past the table and graphs down to the
"Relevant links" section at
https://web.archive.org/web/20180815154501/http://w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html
and you can read more proof.
However, *you cannot ground the elevated radials,* AND *you must use a
proper ferrite choke balun on the coax feedline right at the antenna
feedpoint*.
At
https://web.archive.org/web/20170703105635/http://www.w0btu.com/160_meters.html
scroll down to the section "The W0BTU 160 Meter Inverted-L Antenna" for
very important details about how to use elevated radials effectively.
One missing detail there is that these are "gull-wing" radials. That is,
they slope up at a 45° angle from the feedpoint to 10'.
Sorry there are no photos there.
73, Mike
W0BTU
On Thu, Mar 5, 2020, 12:12 PM Gabriel - EA6VQ via Topband <
topband@contesting.com> wrote:
> I have some doubts about installing and inverted L with elevated radials
> for
> 160m. I have been searching in Google and find some contradictory
> information, so I would appreciate very much if you can help me with your
> own experience.
>
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