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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 ...
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.
A mast radiator or mast antenna is a radio tower or mast in which the whole structure is an antenna. Mast antennas are the transmitting antennas typical for long or medium wave broadcasting. Structurally, the only difference is that some mast radiators require the mast base to be insulated from the ground.
Buried in the ground under the antenna is an enormous radial ground system, which forms the bottom 'plate' of the capacitor with the overhead top load. The antenna must be very large at the VLF frequencies used; the supporting masts are 250–300 metres (820–980 ft) high, and the topload is about 1,900 metres (6,200 ft) in diameter.
Since for an omnidirectional antenna the Earth currents travel radially toward the ground point from all directions, the grounding system usually consists of a radial pattern of buried cables extending outward from the base of the mast in all directions, connected together to the ground lead at a terminal next to the base. [16]
The radials should ideally be long enough to extend beyond the displacement current region near the antenna. At VLF frequencies the resistance of the soil becomes a problem, and the radial ground system is usually raised and mounted a few feet above ground, insulated from it, to form a counterpoise.
Used for elevated base station antennas for land mobile radio systems such as police, ambulance, and taxi dispatchers. Mast radiator A radio tower in which the tower structure itself serves as the antenna. Common form of transmitting antenna for AM radio stations and other MF and LF transmitters.
The system was four times more accurate than the prior Navy AN/GRD-6 system with bearing accuracy better than 0.5 degrees. [2] The Navy AN/FRD-10 was slightly smaller and had a narrower frequency range compared to the Air Force AN/FLR-9 system. [2] The FRD-10 had only 2 antenna rings, 870 feet (270 m) and 780 feet (240 m) diameters. [2]