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oscillator, electronic

(Encyclopedia)oscillator, electronic ŏsˈəlāˌtər [key], electronic circuit that produces an output signal of a specific frequency. An oscillator generally consists of an amplifier having part of its output ret...

Mahama, John Dramani

(Encyclopedia)Mahama, John Dramani drämäˈnē mähäˈmä [key], 1958–, Ghanaian political leader, grad. Univ. of Ghana, Legon (1981, 1986), Institute of Social Sciences, Moscow (1988). A member of the National...

Sarnoff, David

(Encyclopedia)Sarnoff, David, 1891–1971, American pioneer in radio and television, b. Russia. Emigrating to the United States in 1900, he worked for the Marconi Wireless Company, winning recognition as the narrat...

Lee's Summit

(Encyclopedia)Lee's Summit, city (1990 pop. 46,418), Jackson co., W Mo., in the Kansas City metropolitan area; inc. 1868. The city is an important trucking center and manufactures communications equipment, applianc...

tuning systems

(Encyclopedia)tuning systems, methods for assigning pitches to the twelve Western pitch names that constitute the octave. The term usually refers to this procedure in the tuning of keyboard instruments. The need fo...

Santiago, city, Panama

(Encyclopedia)Santiago säntyäˈgō [key], city (1990 pop. 60,959), W central Panama. Santiago is a communications and commercial center in the Pacific lowlands. It is a provincial and district capital. ...

diet, in nutrition

(Encyclopedia)diet, food and drink regularly consumed for nourishment. Nutritionists generally recommend eating a wide variety of foods; however, some groups of people survive on a very limited diet. The traditiona...

dimension, in mathematics

(Encyclopedia)dimension, in mathematics, number of parameters or coordinates required locally to describe points in a mathematical object (usually geometric in character). For example, the space we inhabit is three...

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