Portal:Telecommunication

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Telecommunication

Telecom-icon.svg

Telecommunications refers to wave-based communication technology through media such as air, cables etc. Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded drumbeats, lung-blown horns, or sent by loud whistles, for example. In the modern age of electricity and electronics, telecommunications now also includes the use of electrical devices such as telegraphs, telephones, and teleprinters, the use of radio and microwave communications, as well as fiber optics and their associated electronics, plus the use of orbiting satellites and the Internet.

Show new selections

Selected article

Hammer Ace SATCOM Antenna.jpg

An antenna or aerial is an arrangement of aerial electrical conductors designed to transmit or receive radio waves which is a class of electromagnetic waves. In other words, antennas basically convert radio frequency electrical currents into electromagnetic waves and vice versa. Antennas are used in systems such as radio and television broadcasting, point-to-point radio communication, radar, and space exploration. Antennas usually work in air or outer space, but can also be operated under water or even through soil and rock at certain frequencies for short distances.

Physically, an antenna is an arrangement of conductors that generate a radiating electromagnetic field in response to an applied alternating voltage and the associated alternating electric current, or can be placed in an electromagnetic field so that the field will induce an alternating current in the antenna and a voltage between its terminals. Some antenna devices (parabola, horn antenna) just adapt the free space to another type of antenna.

Selected picture

Amateur Radio Station with multiple receivers and transceivers
Credit: NX1Z

This photograph shows the receivers and transceivers used in an amateur radio station. Amateur radio is a hobby in which enthusiasts purchase or build their own equipment and use radio for their own enjoyment. Radio amateurs are licensed to use frequencies in a large number of narrow bands throughout the radio spectrum.

More selected pictures... Read more...

Things to do


Here are some tasks awaiting attention:

In the news

Selected biography

Nikola Tesla (Serbian Cyrillic: Никола Тесла) (10 July 1856 – 7 January 1943[1]) was an inventor, physicist, mechanical engineer and electrical engineer. Born in Smiljan, Military Frontier, Austria-Hungary, he was an ethnic Serb subject of the Austrian Empire and later became an American citizen. Tesla is best known for his many revolutionary contributions to the discipline of electricity and magnetism in the late 19th and early 20th century. Tesla's patents and theoretical work formed the basis of modern alternating current electric power (AC) systems, including the polyphase power distribution systems and the AC motor, with which he helped usher in the Second Industrial Revolution.

References

Did you know?

...that Intelsat 1, known as Early Bird, launched in 1965, provided either 240 voice circuits or one two-way television channel between the United States and Europe.

...that the first telephone message was transmitted in 1876 from one room in Alexander Graham Bell’s house to another.

...that in 1880 France rewarded Bell the Volta Prize, worth 50,000 francs, for his invention.

Categories

Related portals

Wikimedia

The following Wikimedia sister projects provide more on this subject:
Wikibooks  Wikimedia Commons Wikinews  Wikiquote  Wikisource  Wikiversity  Wiktionary 
Books Media News Quotations Texts Learning resources Definitions

Purge server cache