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The location was selected by AT&T in December 1960. The main factors were the topography (set in the Western Maine Mountains ), and the radio interference signal level. Other factors included a location in the Northeastern United States to give a short great circle path to Western Europe , it was located close enough to existing ...
The diamond-shaped tower was patented by Nicholas Gerten and Ralph Jenner for Blaw-Knox July 29, 1930. [5] and was one of the first mast radiators.[1] [6] Previous antennas for medium and longwave broadcasting usually consisted of wires strung between masts, but in the Blaw-Knox antenna, as in modern AM broadcasting mast radiators, the metal mast structure functioned as the antenna. [1]
The antenna is fed power between the bottom of the mast and ground so it requires a grounding (Earthing) system under the antenna to make contact with the soil to collect the return current. One side of the feedline from the helix house is attached to the mast, and the other side to the ground system.
You can stream a lot of TV online, but for things like the Olympics and breaking news, you'll want a local broadcast station to deliver the goods. Buying an antenna isn't like buying a toaster ...
The system had 120 high band antennas and 40 low band antennas which had to be positioned within +/- two minutes of arc and +/- 3 inches of their intended distance from the center of the array. 160 75 ohm coaxial transmission lines were used to carry signals from the antennas had to be electrically matched to within 3/4 of a degree at 10 MHz.
The antenna array is composed of three concentric rings of antenna elements. Each ring of elements receives RF signals for an assigned portion of the 1.5 to 30-MHz radio spectrum. The outer ring normally covers the 2 to 6-MHz range (band A), but also provides reduced coverage down to 1.5 MHz.
The biconical antenna has a broad bandwidth because it is an example of a traveling wave structure; the analysis for a theoretical infinite antenna resembles that of a transmission line. For an infinite antenna, the characteristic impedance at the point of connection is a function of the cone angle only and is independent of the frequency.
Besides small research and experimental antennas, [5] [6] four full-scale ground dipole installations are known to have been constructed; two by the U.S. Navy at Republic, Michigan and Clam Lake, Wisconsin, [2] [7] [8] one by the Russian Navy on the Kola peninsula near Murmansk, Russia, [8] [9] [10] and one in India at the INS Kattabomman naval ...