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It consists of a network of radial copper wires suspended above the ground, connected to the transmitter feedline ground. It is suspended about 8 feet above ground, so technicians can get access to the helix house at the foot of the tower. Antenna used in Lodge-Muirhead wireless system around 1900, the first counterpoise.
The radial wires either may run above the surface of the earth (elevated radials), on the surface (on ground radials), or buried a centimeter or so under the earth (buried radials). The ends of the wires nearest the antenna base are connected to the antenna system electrical ground, and the far ends are either unconnected, or connected to metal ...
Often random wire antennas are also (inaccurately) referred to as long-wire antennas.There is no accepted minimum size, but actual long-wire antennas must be greater than at least a quarter-wavelength ( 1 / 4 λ) or perhaps greater than a half ( 1 / 2 λ) at the frequency the long wire antenna is used for, and even a half-wave may only be considered "long-ish" rather than "truly ...
A transmatch (antenna tuner) is not required to use this antenna near its nominal design frequency of 14 MHz, and judicious length adjustments can sometimes include one other frequency band. All other frequencies require a transmatch. [citation needed] There are many variants of the G5RV antenna. Two variations of the G5RV design, called ZS6BKW ...
AN-SOF - A Windows simulation software for antennas in free space and above a lossy ground, microstrip patch antennas and printed circuit boards (PCBs). A radial wire ground screen is included and connections to imperfect ground are allowed. Not based on NEC. AutoEZ - An Excel application that works in conjunction with EZNEC v.5.0 & v.6.0 ...
It was laid underground up to the radials in the area between the high and low antennas. [1] Weather proved to be a challenge for the FRD-10 antennas. For example, the antenna at NSGA Winter Harbor had problems due to frost heaving the ground and shifting the reflector screens out of alignment. Digging up the affected poles and replacing them ...
The angle of the slope is usually between 45°–60° and the lower end of the wire is at least 1 ⁄ 6 wavelength above the electrical ground. [3] A sloper is typically fed with a coaxial cable in the center, at the top of the center support mast. At least 1 ⁄ 4 of the wavelength of feedline must be at 90° angle to the antenna. [3]
The RF ground is typically constructed as a star of many radial copper cables buried about 30 cm (1 foot) in the earth, extending out from the base of the vertical wire, and connected together at the center. The radials should ideally be long enough to extend beyond the displacement current region near the antenna.