Ground conductivity's effect on vertical
Ed_G wrote:
Richard,
By "efficient" I was referring to the transfer of power.... to a
presumed 50 ohm antenna input, not to any radiation characteristics !
As I understood it, a half wave vertical can give me this, with a
little effort. I also understood it to have a fairly high take off
angle.... which will certainly give me better in-state coverage than a
good low angle takeoff would..... wouldn't it?
Yes, I know a proper NVIS antenna would be far better than this....
that is why I used the term "some NVIS" characteristics.
TNX
Ed
All the radiation from an antenna isn't concentrated at some "takeoff
angle", but radiates at all angles at various amounts. That distribution
is known as the "elevation pattern" and trying to replace it with a
single "takeoff angle" value loses nearly all the information about how
and where the antenna radiates. The half wavelength vertical radiates
very little above about 60 degrees elevation angle regardless of the
ground characteristics.
Roy Lewallen, W7EL
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