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Telegraph lines continued to be an important means of distributing news feeds from news agencies by teleprinter machine until the rise of the internet in the 1990s. For Western Union, one service remained highly profitable—the wire transfer of money. This service kept Western Union in business long after the telegraph had ceased to be important.
The Electric Telegraph: A Social and Economic History. David and Charles. ISBN 0-7153-5883-9. OCLC 655205099. Mercer, David, The Telephone: The Life Story of a Technology, Greenwood Publishing Group, 2006 ISBN 031333207X; Schwoch, James (2018). Wired into Nature: The Telegraph and the North American Frontier. University of Illinois Press.
The telegraph keys or telephone dial creates trains of on-off current pulses corresponding to the digits 1–9, and 0 (which sends 10 pulses). This equipment originally consisted of two telegraph keys engaged by knife switches, and evolved into the rotary dial telephone. The central office switching equipment has a two-motion stepping switch. A ...
In 1931, the American Telephone and Telegraph Company (AT&T) introduced the Teletypewriter Exchange Service (TWX) which operated over telephone circuits between devices located directly in private businesses. This enabled a secretary to type and send a written message to another TWX machine elsewhere, without using Western Union services, or ...
PBX switchboard, 1975. A telephone switchboard is a device used to connect circuits of telephones to establish telephone calls between users or other switchboards. The switchboard is an essential component of a manual telephone exchange, and is operated by switchboard operators who use electrical cords or switches to establish the connections.
Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades.
Teletype teleprinters in use in England during World War II Example of teleprinter art: a portrait of Dag Hammarskjöld, 1962. A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations.
A telegraph key, clacker, tapper or morse key is a specialized electrical switch used by a trained operator to transmit text messages in Morse code in a telegraphy system. [1] Keys are used in all forms of electrical telegraph systems, including landline (also called wire) telegraphy and radio (also called wireless) telegraphy.