Word: antennas
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...hooked up with a microwave transmission system at M.I.T., with WGBH, and potentially with a larger Boston-Cambridge community antenna television system. Community events could be televised live. Visual study projects, lectures, seminars and films could be taped and transmitted...
...more precise than any they have ever had before. It is a huge, 328-ft. paraboloid nestled in West Germany's Eifel hills at Effelsberg, about 25 miles southwest of Bonn. More than 75 feet larger than the existing record holder, Britain's big Jodrell Bank radio antenna, the steel-and-aluminum instrument is now undergoing its final checkouts before it begins scanning the heavens in earnest this fall...
Crude Beginnings. In spite of the physical differences, such sensitive radio telescopes operate much like their optical cousins. Instead of gathering ordinary light, they use their big reflectors to capture the radio energy from the invisible part of the electromagnetic spectrum. The curved surface of the antenna acts just like a lens, bringing the radio waves to sharp focus at a point in front of the dish. There they are picked up by a smaller antenna and piped into the telescope's electronic amplifier. The signals may be translated into audible sounds, traced out by pen-and-ink graph...
Meticulous Design. The first radio telescope, a crude antenna that turned on wheels cannibalized from a Model T Ford, was made 40 years ago by a Bell Labs scientist named Karl Jansky. In contrast, the new German instrument is a model of engineering sophistication. The entire telescope can be rotated a full 360° on a circular railroad-type track in only nine minutes. Its plate-and-mesh reflector can be tilted 90° from a point directly overhead to the horizon in only half that time. Furthermore, the telescope has been so meticulously designed that the stresses caused...
...hooked up with a micro wave transmission system at M.I.T.; with WGBH, and ultimately with a larger Boston-Cambridge community antenna television system. Community events could be televised live. Visual study projects, lectures, seminars, and films could be taped and transmitted...