4.
Bent Antennas.
a. A bent antenna is a compromise antenna when not enough room
exists to install a horizontal antenna or supports high enough to
erect a vertical antenna are not available.
b. Inverted L antennas come in varied configurations.
One
configuration is a half wave. The flattop portion could be a quarter
wave with a counterpoise as the other quarter wave. See figure 63.
Another configuration is only a quarter-wave long.
The horizontal
portion is an eighth wave and the down lead is the other eighth wave.
The other quarter wave is a ground return, a radial, or a
counterpoise may be used.
Figure 63.
Inverted-L military antenna.
5.
Ground Plane Antenna.
a. A ground plane antenna is an antenna with a vertical section
of a quarter wave in length, and with spokes, normally three or four
in number, each of which is a quarter wave or longer in length. The
spokes form the artificial ground. The ground plane is used at VHF
(30 - 300 MHz) and higher frequencies. The ground plane is normally
mounted on top of a mast and is called an elevated ground plane
antenna.
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