The antenna's take off angle is the angle above the horizon that an antenna radiates the largest amount of energy (see figure.2.8) VHF communications antennas are designed so that the energy is radiated parallel to the earth (do not confuse take-off angle and polaration).The take-off angle of an HF communications antenna can determine whether a circuit is successful or not.HF sky wave antennas are designed for specific take-off angles,depending on the circuit distance.High take-off angles are used for short range communication and low take-off angles are use for long range communications.
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