Ad
related to: full wave 2 meter vertical antenna length guide freewalmart.com has been visited by 1M+ users in the past month
Search results
Results from the WOW.Com Content Network
The AT&T receiving Beverage antenna (left) and radio receiver (right) at Houlton, Maine, used for transatlantic telephone calls, from a 1920s magazine. 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]
Traveling wave antennas Traveling wave antennas are notably one of the few types of antennas that are normally not self resonant: Electrical waves induced by received radio waves travel through the antenna wire in the direction that the arriving RF signals are travelling. Only electrical waves traveling toward the feedpoint are collected; waves ...
The 2-meter amateur radio band is a portion of the VHF radio spectrum that comprises frequencies stretching from 144 MHz to 148 MHz [1] in International Telecommunication Union region (ITU) Regions 2 (North and South America plus Hawaii) and 3 (Asia and Oceania) [2] [3] and from 144 MHz to 146 MHz in ITU Region 1 (Europe, Africa, and Russia).
The length of a whip antenna is determined by the wavelength of the radio waves it is used with. Their length varies from compact electrically short antennas 1 / 10 wavelength long, up to 5 / 8 wavelength to improve directivity. The most common type is the quarter-wave whip, which is approximately 1 / 4 wavelength long.
The gain continues to increase up to a maximum of about 3 dB over a quarter-wave monopole at a length of five-eighths wavelength so this is a popular length for ground wave antennas and terrestrial communication antennas. The radiation resistance drops to about 53 ohms at that length.
[6]: 14 Vertical antennas must be used because VLF waves propagate in vertical polarization, but a quarter-wave vertical antenna at 30 kHz (10 km wavelength) would be 2.5 kilometres (8,200 feet) high. So practical transmitting antennas are electrically short, a small fraction of the length at which they would be self-resonant.
Orr (1996) [13] shows a 10, 15, and 20 meter, 2 element quad with boom length of 6′10″. Internally stackable Interaction between antennas of a multiband quad are quite low, even when fed with a single feed line, [ 14 ] so higher frequency (smaller) quad loops can be nested in lower frequency (bigger) quad loops, allowing operation on as ...
The vertical plane is used to plot an antenna's relative field strength perpendicular to the ground (which directly affects a station's coverage area) on a polar graph. Normally, the maximum of 1.000 or 0 dB is at the side (unless there is beam tilt), which is labeled 0°, to 90° at the top and −90° at the bottom.
Ad
related to: full wave 2 meter vertical antenna length guide freewalmart.com has been visited by 1M+ users in the past month