> Looking at the picture of current distribution in EZNEC
> model shows that the current in the radiator would be the
> same in both cases and in the top loading with L or T is
> either all (corresponding portion) radiated (horizontal in
> L) or cancelled (in balanced T).
Actually Eznec shows the radiation resistance of an Inverted
L goes down (meaning current increases for the same power)
when going from an L to a T. With both antennas resonant,
1000 watts, and a 50 foot vertical section over perfect
ground:
Inverted L
14.25 ohms
8.38 amps
T antenna
12.7 ohms
8.88 amps
The maximum radiation from the horizontal section of this
50 foot high L over average ground is about 10dB below the
maximum radiation of the vertical section. Then horizontal
section does fill in the high angle null, but weakly
compared to just switching to a low dipole.
It probably doesn't matter which type is used in the real
world, they are so close. It's probably a matter of the
space people have than any significant performance
difference. By the way, without a rotating wave it is
impossible for horizontal and vertical polarization to exist
at any fixed point in space. The Inverted L like many
antenna has a pattern that tilts polarization gradually as
the azimuth and elevation is changed. At any one direction
and angle the wave is a single polarization, not a mixture.
73 Tom
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