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Branly, Édouard

(Encyclopedia)Branly, Édouard ādwärˈ bräNlēˈ [key], French physicist and physician. He was professor of physics at the Catholic Institute, Paris, from 1875. He developed (1890) a coherer for the detection of...

static

(Encyclopedia)static, term formerly use to describe electrical noise in radio reception, especially noise that originates outside a transmitter and receiver, e.g., in the atmosphere or in human-made devices. In gen...

magnetic resonance imaging

(Encyclopedia)magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. The patient lies...

Shklovsky, Iosif Samuilovich

(Encyclopedia)Shklovsky, Iosif Samuilovich yôsˈĭf səmo͞oēlˈəvĭch shklŏfˈskē [key], 1916–85, Soviet astronomer. He was head of the department of radio-astronomy at the Sternberg Astronomical Institute,...

direction finder

(Encyclopedia)direction finder, electronic device used to determine the position of a ship or aircraft. In a simple direction finder a radio receiver is equipped with a revolving directional antenna. The antenna re...

Rockefeller Center

(Encyclopedia)Rockefeller Center, complex of buildings in central Manhattan, New York City, between 48th and 51st streets and Fifth Ave. and the Ave. of the Americas (Sixth Ave.). The project was sponsored by John ...

Voice of America

(Encyclopedia)Voice of America, broadcasting service of the United States Information Agency, est. 1942. Originally set up as a means of fighting the cold war, the Voice of America produces and broadcasts radio pro...

sideband

(Encyclopedia)sideband, any frequency component of a modulated carrier wave other than the frequency of the carrier wave itself, i.e., any frequency added to the carrier as a result of modulation; sidebands carry t...

RFID

(Encyclopedia)RFID: see radio-frequency identification. ...