Broadcasting - Radio and Television

Broadcasting - Radio and Television

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Broadcasting is a crucial instrument of modern social and political organization. At its peak of influence in the mid-20th century, radio and television broadcasting was employed by political leaders to address entire nations. Because of radio and television's capacity to reach and influence large numbers of people, and owing to the limited spectrum of frequencies available, governments have commonly regulated broadcasting wherever it has been practiced. In the early 1980s, new technologies--such as cable television and videocassette players--began eroding the dominance of broadcasting in mass communication, splitting audiences into smaller, culturally distinct segments. Previously the only means of delivering radio and television to home receivers, broadcasting is now just one of several delivery systems available to listeners and viewers. Sometimes broadcasting is used in a broader sense to include delivery methods such as wire-borne (cable) transmission, but these are more accurately called "narrowcasting" because they are generally limited to paying subscribers. II THE EMERGENCE OF BROADCAST COMMUNICATION For most of history, long-distance communication depended primarily upon conventional means of transportation. A message could be moved aboard a ship, on horseback, by pigeon, or with a human courier, but in virtually all cases it had to be conveyed as a mass through space like any other material commodity. This basic condition of human communication ended in the 19th century due to a series of technological advances. A Radio Broadcasting The story of radio begins in the development of an earlier medium, the telegraph, which was the first instantaneous system of information movement. Patented simultaneously in 1837 in the United States by inventor Samuel F. B. Morse and in Britain by scientists Sir Charles Wheatstone and Sir William Fothergill Cooke, the electromagnetic telegraph realized the age-old human desire for a means of communication free from the obstacles of long-distance transportation. The first public telegraph line, completed in 1844, ran 64 km (40 mi) from Washington, D.C., to Baltimore, Maryland. Morse's first message, "What hath God wrought?"--transmitted as a coded series of long and short electronic impulses--conveyed his awareness of the momentous proportions of the achievement. Telegraphy proved so useful and popular that over the next half century wires were strung across much of the world, including a transatlantic undersea cable (1866) connecting Europe and North America. The instantaneous passage of a message over a distance that required hours, days, or weeks to traverse by ordinary transport was so radically unfamiliar an experience that some telegraph offices collected admission fees from spectators wanting to witness the feat for themselves. As society began to depend on the telegraph for everything from birthday greetings to the news of momentous events, the limitations of telegraphic communication became apparent. Telegraphy depended on the building and maintenance of a complex system of receiving stations wired to each other along a fixed route and requiring trained operators to transmit and receive messages. The telephone, patented by Scottish-born American inventor Alexander Graham Bell in 1876, made instantaneous communication possible via a desktop appliance available to untrained users. However, it required an even more complex system of wires and switching stations than the telegraph. Neither device could be used by ships at sea or reach the many remote communities that could not afford the costs of lines and stations. Although neither the telephone nor the telegraph could address large numbers of people simultaneously, mass circulation newspapers and magazines benefited greatly from the two devices, translating wired reports into print for mass consumption. News agencies such as the Associated Press and Reuters are still often called wire services, referring to their beginnings as telegraph services.

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