Let's design a short antenna just for fun
Jeff wrote:
I would think a dipole would be a bad candidate for a "short" antenna
as you need to get the matching stuff close to the antenna to avoid
I^2R losses.
Some sort of ground mounted, or close to the ground, antenna might
make a better choice.
A dipole may be a better candidate, if you use a monopole then although
you will be able to put your matching close to the antenna, providing an
effective earth screen becomes vital and earth losses may outweigh any
advantage.
Of course if you do use a dipole it is vital that any matching is at the
feed point and not on the end of a length of coax or the losses will soar.
The issue with dipoles is height.
As the height of a dipole decreases below 1/2 wavelength the pattern
elevation angle starts increasing and very quickly has most of the
energy going straight up.
At 160M that means getting the dipole 260 feet up in the air, and if
you can do that, why would you be concerned about a short antenna
as a full 1/4 wave 160M antenna is only about 140 feet tall?
--
Jim Pennino
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