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Shortwave Relay Station
Shortwave relay stations are transmitter sites used by international broadcasters to extend their coverage to areas that cannot be reached easily from their home state. For example, the BBC operates an extensive net of relay stations. These days the programs are fed to the relay sites by satellite, cable/optical fiber or the Internet. Frequencies, transmitter power and antennas depend on the desired coverage. Some regional relays even operate in the medium wave or FM bands. Relay stations are also important to reach listeners in countries that practice radio jamming. Depending on the effect of the shortwave dead zone the target countries can jam the programs only locally, e.g. for bigger cities. For this purpose Radio Free Europe/Radio Liberty with studios in Munich, Germany operated a relay station in Portugal, in the extreme west of Europe, to reach then-communist Eastern Europe. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sistema HR ALLISS
AFK Sistema PAO is a large Russian conglomerate company, founded by Vladimir Yevtushenkov, who was chairman of the corporation's board of directors until 2022. In April, Yevtushenkov's shareholding in Sistema has decreased to 49.2%, and he also stepped down from Sistema's board. Sistema has its headquarters in Moscow. The company's global depository receipts (GDRs) are traded on the London Stock Exchange (ticker symbol ). History In 1993, Evgeny Novitsky and Vladimir Yevtushenkov founded the holding company AFK Sistema, also known as Sistema JSFC, to group together several information technology (IT) and cell phone companies including MTS. Structure Sistema operates a number of consumer service businesses in the areas of: * IT and telecoms — Mobile TeleSystems, Moscow City Telephone Network, SkyLink, Sitronics (formerly known as 'Science Center Concern'), NIIME, Mikron, STROM telecom. * Banking — MTS Bank * E-commerce – Ozon * House-Building and Real Estate — Sistema ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency Antenna Types
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by another antenna connected to a radio receiver. Radio is very widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency Propagation
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by another antenna connected to a radio receiver. Radio is very widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Broadcasting
International broadcasting, in a limited extent, began during World War I, when German and British stations broadcast press communiqués using Morse code. With the severing of Germany's undersea cables, the wireless telegraph station in Nauen was the country's sole means of long-distance communication. The US Navy Radio Service radio station in New Brunswick, Canada, transmitted the 'Fourteen Points' by wireless to Nauen in 1917. In turn, Nauen station broadcast the news of the abdication of Kaiser Wilhelm II on November 10, 1918. History Origins Guglielmo Marconi pioneered the use of short wave radio for long-distance transmissions in the early 1920s. Using a system of parabolic reflector antennae, Marconi's assistant, Charles Samuel Franklin, rigged up a large antenna at Poldhu Wireless Station, Cornwall, running on 25 kW of power. In June and July 1923, wireless transmissions were completed during nights on 97 meters from Poldhu to Marconi's yacht ''Elettra'' in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperial Wireless Chain
The Imperial Wireless Chain was a strategic international communications network of powerful long range radiotelegraphy stations, created by the British government to link the countries of the British Empire. The stations exchanged commercial and diplomatic text message traffic transmitted at high speed by Morse code using paper tape machines. Although the idea was conceived prior to World War I, the United Kingdom was the last of the world's great powers to implement an operational system.Empire Wireless Papers Past, Evening Post (New Zealand), published 1923-04-23, accessed 2010-10-03 The first link in the chain, between Leafield in Oxfordshire and |
Broadcast Relay Station
A broadcast relay station, also known as a satellite station, relay transmitter, broadcast translator (U.S.), re-broadcaster (Canada), repeater ( two-way radio) or complementary station (Mexico), is a broadcast transmitter which repeats (or transponds) the signal of a radio or television station to an area not covered by the originating station. It expands the broadcast range of a television or radio station beyond the primary signal's original coverage or improves service in the original coverage area. The stations may be (but are not usually) used to create a single-frequency network. They may also be used by an AM or FM radio station to establish a presence on the other band. Relay stations are most commonly established and operated by the same organisations responsible for the originating stations they repeat. However, depending on technical and regulatory restrictions, relays may also be set up by unrelated organisations. Types Broadcast translators In its simplest f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio France Internationale
Radio France Internationale, usually referred to as RFI, is the state-owned international radio broadcaster of France. With 37.2 million listeners in 2014, it is one of the most-listened-to international radio stations in the world, along with Deutsche Welle, the BBC World Service, the Voice of America, Radio Netherlands Worldwide, and China Radio International. RFI broadcasts 24 hours per day around the world in French and in 12 other languages in FM, shortwave, medium wave, satellite and on its website. It is a channel of the state company France Médias Monde. The majority of shortwave transmissions are in French and Hausa but also includes some hours of Swahili, Portuguese, Mandinka, and Russian. RFI broadcasts to over 150 countries on 5 continents. Africa is the largest part of radio listeners, representing 60% of the total audience in 2010. In the Paris region, RFI comprises between 150,000 and 200,000 listeners. In 2007, the audience was of 46.1 million listeners, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TDF Group
TDF (which stands for ''Télédiffusion de France'' officially renamed ''TDF'' in 2004) is a French company which provides radio and television transmission services, services for telecommunications operators, and other multimedia services – digitization of content, encoding, storage, etc. Its headquarters are located in Paris. It is the dominant partner in the HDRR WiMAX consortium and is also part of Digital Radio Mondiale. Arkena Arkena was European company that regroups four entities: Cognacq-Jay Image (France), PSN (Poland), Qbrick (Sweden) and SmartJog (France). These entities were all part of the Media Services division of the TDF Group. http://www.broadbandtvnews.com/2014/01/20/arkena-joins-together-all-tdf-media-subsidiaries/ - Broadband TV News, 20 January 2014 Arkena provides full ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint-Aoustrille
Saint-Aoustrille () is a commune in the Indre department in central France. It is named after the 7th-century Saint Austregisilus. Population See also *Communes of the Indre department The following is a list of the 241 communes of the Indre department of France. The communes cooperate in the following intercommunalities (as of 2020):Communes of Indre {{Indre-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Issoudun
Issoudun () is a commune in the Indre department, administrative region of Centre-Val de Loire, France. It is also referred to as ''Issoundun'', which is the ancient name. Geography Location Issoudun is a sub-prefecture, located in the east of the Indre department. It is in the former region of Berry. The surrounding communes are: * Les Bordes (4 km) * Saint-Aoustrille (5 km) * St. Lizaigne (7 km) * Chouday (7 km) * Lizeray (8 km) * Condé (8 km) * Thizay (8 km) * Saint-Georges-sur-Arnon (10 km) * Saint-Ambroix (10 km) * Saugy (10 km) * Saint-Aubin (11 km) * Châteauroux (27 km) * Châtre (41 km) * Le Blanc (79 km) Terrain The river of Théols passes through Issoudun. The commune of Issoudun takes up an area of 36.6 km². Transport The national road N151 passes through the area. The nearest airport is the Marcel Dassault Airport, 27 km away. The Issoudun station is located at 4 Pierre Favrea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Direction Finding
Direction finding (DF), or radio direction finding (RDF), isin accordance with International Telecommunication Union (ITU)defined as radio location that uses the reception of radio waves to determine the direction in which a radio station or an object is located. This can refer to radio or other forms of wireless communication, including radar signals detection and monitoring (ELINT/ESM). By combining the direction information from two or more suitably spaced receivers (or a single mobile receiver), the source of a transmission may be located via triangulation. Radio direction finding is used in the navigation of ships and aircraft, to locate emergency transmitters for search and rescue, for tracking wildlife, and to locate illegal or interfering transmitters. RDF was important in combating German threats during both the World War II Battle of Britain and the long running Battle of the Atlantic. In the former, the Air Ministry also used RDF to locate its own fighter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
