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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 ...
[citation needed] To perform adequately, the counterpoise should extend at least half a wavelength from the antenna tower in all directions. [8] In designing a counterpoise for a medium-wave radio station, for example, radio-waves are a maximum of 566 metres (1,857 ft) long. Therefore, the counterpoise should extend 282 metres (925 ft) from the ...
The Beverage antenna or "wave antenna" is a long-wire receiving antenna mainly used in the low frequency and medium frequency radio bands, invented by Harold H. Beverage in 1921. [1] It is used by amateur radio operators, shortwave listeners, longwave radio DXers and for military applications.
Assuming the building is about 20 feet tall, the length of wire seems to be on the order of 100 feet long – too short to be an HF Beverage antenna. Random wire antenna Moxon (1993) describes the random-wire antenna as an "odd bit of wire". [15] [page needed] It is the typical informal antenna erected for receiving shortwave and AM radio.
A rhombic antenna is made of four sections of wire suspended parallel to the ground in a diamond or "rhombus" shape. Each of the four sides is the same length – about a quarter-wavelength to one wavelength per section – converging but not touching at an angle of about 42° at the fed end and at the far end.
In antennas built for frequencies near or below 600 kHz [b], the length of an antenna's wire segments is usually shorter than a quarter wavelength [c] [ 1 / 4 λ ≈ 125 m (410 feet) [c] at 600 kHz [b]], the shortest length of unloaded straight wire that achieves resonance. [5]
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 ...
This simplified arrangement has several advantages, including a shorter ground distance between the ends. For example, a dipole antenna for the 80 meter band requires a ground length of about 140 feet (43 m) from end to end. An inverted vee with a 40-foot (12 m) apex elevation requires only 115 feet (35 m).