Word: antennas
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...bowl-shaped antenna pointed straight up. Above it floated an object that looked for all the world like a small, square bedspring with a tiny helicopter attached. The rotor blades whirled with a thin whine, and the helicopter strained at the guy wires that kept it from climbing more than 50 ft. There it hovered, its blades spinning sturdily, drawing their power out of invisible microwaves shooting up from below. This was Raytheon Co.'s first public demonstration of an aircraft powered solely by radio energy...
...wires, are needed to intercept Raytheon's beam. In the model helicopter demonstrated last week, they feed direct current at about 100 volts to a small motor taken from an electric drill. The beam of 2,450-megacycle microwaves starts out with three kilowatts of power; the diode antenna turns it into electricity with an efficiency of about...
Near-Perfect Parabola. Haystack is the property of the Air Force, was designed and built by M.I.T.'s Lincoln Laboratory and North American Aviation Inc. for $15 million. Of the total cost, $5,000,000 went in fees for computers, which designed and redesigned the antenna 42 times. The painstaking expense was worth it, producing an antenna that misses, by the thickness of a paper match, being a perfect parabola. Haystack can resolve objects down to 1/60th of a degree, could zero in on an area of the moon just 225 miles in diameter v. 4,500 miles...
...give the 171-ton Haystack its phenomenal accuracy required miracles of designed precision. The huge aluminum antenna floats, for instance, on a film of oil not much thicker than a human hair, moves on a 30-ton bearing with the ease of a ship's gyro. The oil bearing eliminates what engineers call "stiction," for static friction, enables the antenna to rotate through more than three degrees of arc in less than one second, make a complete 180-degree about-face in less than one minute. With such agility, Haystack can track anything that can be tossed into space...
Magnetic Memory. Haystack's radio antenna will also be the most versatile anywhere in the free world. By changing transmitters and receivers it can be used as a superradar, radio telescope, or a radio transmitter to talk to and listen to communications satellites or spacecraft probing the planets. Haystack is so sensitive, and its tasks so enormous, that its operation could never be entrusted to mere men. The antenna beam will be pointed by a Univac 490, which will be able to call on a magnetic memory with a complete astronomical almanac for the sun, moon and eight planets...