Figure 43. A Typical Doublet.
Figure 44. Doublet for path of 100 miles or less, showing
use and placement of counterpoise.
2. The 14 percent off-center fed antenna.
The antenna is a wire
which is a half wave in length.
The feed line is a single wire
attached to the antenna 14 percent from the center.
A counterpoise
may be used to reduce the absorption of the ground reflected wave.
The transmission line should be at right angles to the antenna to
reduce radiation and coupling back to the antenna.
See figure 45.
The radiation resistance is 500 to 600 ohms. Your transmitter would
need an antenna tuning unit to load this antenna, or the transmitter
would have to have the capability of loading antennas over a wide
high power loss.
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