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10 Cards in this Set
- Front
- Back
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What are the two basic classifications of antennas?
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Half-wave (Hertz) and quarter-wave (Marconi)
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What are the three parts of a complete antenna system?
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Coupling device, feeder, and antenna
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What three factors determine the type, size, and shape of an antenna?
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Freguency, power, general direction.
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What is the term used to identify the points of high current and high voltage on an antenna?
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Current and voltage loops.
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What is the term used to identify the points of minimum current and minimum voltage on an antenna?
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Current and voltage nodes.
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The direction of what field is used to designate the polarization of a wave?
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Electric field.
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If a wave's electric lines of force rotate through 360 degrees with every cycle of rf energy, what is the polarization of this wave?
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Circular polarization
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What type of polarization should be used at medium and low frequencies?
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Vertical polarization.
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What type of polarization should be used if an antenna is mounted on a moving vehicle at frequencies below 50 megahertz?
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Vertical polarization.
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What is the radiation resistance of a half-wave antenna in free space?
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73 ohms.
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