Portal:Telecommunication
The Telecommunication Portal
Telecommunication, often used in its plural form, is the transmission of information with an immediacy comparable to face-to-face communication. As such, slow communications technologies like postal mail and pneumatic tubes are excluded from the definition. Many transmission media have been used for telecommunications throughout history, from smoke signals, beacons, semaphore telegraphs, signal flags, and optical heliographs to wires and empty space made to carry electromagnetic signals. These paths of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent communication sessions. Several methods of long-distance communication before the modern era used sounds like coded drumbeats, the blowing of horns, and whistles. 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. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Other early pioneers in electrical and electronic telecommunications include co-inventors of the telegraph Charles Wheatstone and Samuel Morse, numerous inventors and developers of the telephone including Antonio Meucci and Alexander Graham Bell, inventors of radio Edwin Armstrong and Lee de Forest, as well as inventors of television like Vladimir K. Zworykin, John Logie Baird and Philo Farnsworth.
Since the 1960s, the proliferation of digital technologies has meant that voice communications have gradually been supplemented by data. The physical limitations of metallic media prompted the development of optical fibre. The Internet, a technology independent of any given medium, has provided global access to services for individual users and further reduced location and time limitations on communications. (Full article...)
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The concept of television is the work of many individuals in the late 19th and early 20th centuries. The first practical transmissions of moving images over a radio system used mechanical rotating perforated disks to scan a scene into a time-varying signal that could be reconstructed at a receiver back into an approximation of the original image. Development of television was interrupted by the Second World War. After the end of the war, all-electronic methods of scanning and displaying images became standard. Several different standards for addition of color to transmitted images were developed with different regions using technically incompatible signal standards. Television broadcasting expanded rapidly after World War II, becoming an important mass medium for advertising, propaganda, and entertainment.
Television broadcasts can be distributed over the air by VHF and UHF radio signals from terrestrial transmitting stations, by microwave signals from Earth orbiting satellites, or by wired transmission to individual consumers by cable television. Many countries have moved away from the original analog radio transmission methods and now use digital television standards, providing additional operating features and conserving radio spectrum bandwidth for more profitable uses. Television programming can also be distributed over the Internet. (Full article...)General images
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John Logie Baird FRSE (/ˈloʊɡi bɛərd/; 13 August 1888 – 14 June 1946) was a Scottish inventor, electrical engineer, and innovator who demonstrated the world's first live working television system on 26 January 1926. He went on to invent the first publicly demonstrated colour television system and the first viable purely electronic colour television picture tube.
In 1928 the Baird Television Development Company achieved the first transatlantic television transmission. Baird's early technological successes and his role in the practical introduction of broadcast television for home entertainment have earned him a prominent place in television's history. (Full article...)Did you know (auto-generated) -
- ... that Lucy Feagin founded the Feagin School of Dramatic Art in New York City, where talent scouts for radio, screen, and stage were always present to watch her senior students' plays?
- ... that Red Blanchard, the owner of Iowa radio station KSMN, commuted 800 miles (1280 km) by plane from Mason City each week to host a radio show in Chicago?
- ... that Sunday-school classes were once held in the transmitter building of New Mexico radio station KCLV?
- ... that the owner of a Pennsylvania radio station compared his job to that of Lee Iacocca at Chrysler?
- ... that in Jackson, Tennessee, there was a 50–50 chance a reference to Dixie was about a radio station?
- ... that the government radio station in Mandatory Palestine had an Arab Hour in the late 1930s hosting Palestinian writers like Stephan Hanna Stephan?
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