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Communications Satellite Corporation

(Encyclopedia)Communications Satellite Corporation (Comsat), organization incorporated (1962) by an act of Congress to establish a commercial system of international communications using artificial satellites. Alth...

decibel

(Encyclopedia)decibel dĕsˈəbĕlˌ, –bəl [key], abbr. dB, unit used to measure the loudness of sound. It is one tenth of a bel (named for A. G. Bell), but the larger unit is rarely used. The decibel is a measu...

over-the-counter

(Encyclopedia)over-the-counter, method of buying and selling securities outside the organized stock exchange. Unlike an organized stock exchange, the over-the-counter market is composed of dealers who negotiate mos...

Woods, Granville Taylor

(Encyclopedia)Woods, Granville Taylor,, 1856–1910, African-American inventor, b. Columbus, Ohio. He worked in a railroad shop as a youth, becoming a machinist and blacksmith. He subsequently worked on trains, fir...

local area network

(Encyclopedia)local area network (LAN), a computer network dedicated to sharing data among several single-user workstations or personal computers, each of which is called a node. A LAN can have from two to several ...

Jansky, Karl Guthe

(Encyclopedia)Jansky, Karl Guthe, 1905–50, American radio engineer; b. Norman, Okla. After graduating (1927) from the Univ. of Wisconson, he joined the Bell Telephone Laboratories. While trying to determine the c...

digital-to-analog conversion

(Encyclopedia)digital-to-analog or D/A conversion, the process of changing discrete digital data into a continuously varying signal in relation to a standard or reference. There are two types of converters: electro...

Levitt, William Jaird

(Encyclopedia)Levitt, William Jaird lĕvˈət [key], 1907–94, American builder, b. Brooklyn, N.Y. After studying at New York Univ., he (and his brother) joined his father's construction company; it became (1929) ...

multiplexing

(Encyclopedia)multiplexing, in communication, technique whereby two or more independent messages, or information-bearing signals, are carried by a single common medium, or channel. When multiplexing is performed, t...

histone

(Encyclopedia)histone hĭsˈtōn [key], any of a class of protein molecules found in the chromosomes of eukaryotic cells. They complex with the DNA (see nucleic acid) and pack the DNA into tight masses of chromatin...