Figure 2-22.—Quadrant antenna.
WHIP ANTENNAS
Hf whip antennas (fig. 2-23) are vertically-polarized omnidirectional monopoles that are used for short-range, ship-to-shore and transportable communications systems. Whip antennas are made of tubular metal or fiberglass, and vary in length from 12 feet to 35 feet, with the latter being the most prevalent. Although whips are not considered as highly efficient antennas, their ease of installation and low cost provide a compromise for receiving and low-to-medium power transmitting installations.
The self-supporting feature of the whip makes it particularly useful where space is limited. Whips can be tilted, a design feature that makes them suited for use along the edges of aircraft carrier flight decks. Aboard submarines, they can be retracted into the sail structure.
Most whip antennas require some sort of tuning system and a ground plane to improve their radiation efficiency throughout the hf spectrum. Without an antenna tuning system, whips generally have a narrow bandwidth and are limited in their power handling
2-13
