"A",
"B",
"C",
"D",
"E",
"F",
"G"/"H",
"I"/"J"/"K"/"L",
"M"/"N"/"O",
"P"/"Q",
"R",
"S",
"T",
"U"/"V"/"W"/"X"/"Y"/"Z"
UHF: Refer to Ultrahigh frequency.
Ultrahigh frequency: [UHF] Frequencies between 300 and 3,000 MHz. Used for TV channels 14-51 [470MHz to 698MHz]
Unbalanced transmission line: A transmission line one of whose
conductors is grounded.
Unidirectional: In one direction only.
Unidirectional Array: An array that radiates in only one general direction.
Uniform Linear Array: An antenna composed of a
relatively large number of usually identical elements
arranged in a single line or in a plane with uniform
spacing and usually with a uniform feed system.
V Antenna. A bidirectional antenna, shaped like a V, which is widely used for communications. An antenna whose elements are in the shape of a 'V'. [Antenna Manufacturers]
Vee antenna: Two long-wire antennas connected to form a vee.
Velocity: The speed of a radio wave through the dielectric medium
it is in.
Vertical dipole: A balanced or dipole antenna oriented vertically.
Vertical polarization: Transmission of radio waves in such a way
that the electric lines of force are vertical (perpendicular to the
Earth’s surface).
Vertical quarter-wave antenna: A monopole (whip) antenna that
is oriented vertically.
Very high frequency: [VHF] Frequencies between 30 and 300 MHz;
transmissions that follow the line of sight path. Used for TV channels 2-13 [54MHz to 216MHz]
Voltage: Electrical pressure, expressed in volts, which is the result
of squeezing electrons together.
Voltage standing-wave ratio: [VSWR] The ratio of the amplitude of the
electric field or voltage at a voltage maximum to that at an adjacent
voltage minimum. Also called VSWR.
Wave Antenna. Same as Beverage Antenna.
Waveguide: A hollow metal tube used as a transmission line to guide energy from one point to another. [WaveGuide Manufacturers]
Wavelength: The distance a wave travels during one complete
cycle. It is equal to the velocity divided by the frequency.
wave propagation—The transmission of RF energy through space.
Whip antenna: A vertical monopole. A flexible rod antenna, usually
between 1/10 and 5/8 wavelength long, supported on
a base insulator. [Antenna Manufacturers]
Whip Antenna
Wire: Conductors in one of many different sizes with different kinds of insulation. [Wire Manufacturers]
Yagi Reflector
Yagi Antenna. A multi-element parasitic array. The elements lie in the same plane as those of the end-fire array. A linear end-fire antenna, consisting of three or more half-wave elements (one driven, one reflector, and one or more directors). A Yagi antenna offers very high directivity and gain. The formal name for a “Yagi antenna” is “Yagi-Uda array.”
Zeppelin Antenna: Text in review.
