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Start Point Transmitting Station
The Start Point transmitting station is a broadcasting facility at Start Point, Devon, owned by Arqiva. The site is just north-west of the Start Point lighthouse. The station currently transmits a single broadcast: BBC Radio 5 Live on 693 kHz. History 1930s In 1935 the BBC started looking for transmitter sites to improve radio coverage in Devon, Dorset and Cornwall. After investigating 23 sites and carrying out extensive tests, two sites were selected: Start Point and Clevedon in Somerset. Start Point came on air on 14 June 1939 using an ST&C type C100 100 kW transmitter on 1050 kHz, and broadcast the West of England regional programme. A directional aerial array was used to avoid wasting power over the English Channel and to enhance the signal to the east and west. It consisted of two stayed lattice masts, one being a mast radiator and the other a parasitic reflector. Both masts had a break at to allow for the insertion of a loading coil.Pawley, Edward (1972 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Start Point, Devon
Start Point is a promontory in the South Hams district in Devon, England, . Close to the most southerly point in the county, it marks the southern limit of Start Bay, which extends northwards to the estuary of the River Dart. The rocks of the point are greenschist and mica-schist, formed by metamorphism Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of ch ... of Devonian sediments during a period of mountain building towards the end of the Carboniferous period. The name "Start" derives from an Anglo-Saxon word ''steort'', meaning a tail. This root also appears in the names of birds with distinctive tails, like the redstart. Features As a result of the many shipwrecks in the area, Start Point lighthouse was built in 1836 to alert ships to the danger of the point and its surrou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Reflector
In an antenna array made of multiple conductive elements (typically metal rods), a driven element or active element is electrically connected to the receiver or transmitter while a parasitic element or passive radiator is not. Driven elements In a multielement antenna array (such as a Yagi–Uda antenna), the driven element or active element is the element in the antenna (typically a metal rod) which is electrically connected to the receiver or transmitter. In a transmitting antenna it is ''driven'' or ''excited'' by the radio frequency current from the transmitter, and is the source of the radio waves. In a receiving antenna it collects the incoming radio waves for reception, and converts them to tiny oscillating electric currents, which are applied to the receiver. Multielement antennas like the Yagi typically consist of a driven element, connected to the receiver or transmitter through a feed line, and a number of other elements which are not driven, called parasitic e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stokenham
Stokenham ( təʊ̯kən'hæm not stəʊ̯kənəm being a break with other comparators in England) is a village and civil parish in the English county of Devon. The population of the parish at the 2011 census was 1,895. Places in the parish As well as Stokenham the civil parish includes the settlements of Torcross, Beesands, Hallsands, Kellaton, Kernborough, Dunstone, Beeson and Chillington and Bickerton. It forms part of the district of South Hams. History The village of Stokenham was known in Saxon Times as Stoc or ''Stoc Hamme'' ("meaning Stoc meadows"). By the 13th century the town was called Stoke in Hamme. An electoral ward has the same name. The ward population at the 2011 census was 1,895. In Mediaeval times St. Humbert the Confessor (d.1188AD) was locally venerated as patron saint in the town. The area was known in the 19th century for the fine crabs, and in World War II local residents were evacuated from the area, on the eve of D-day. Geography To t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buildings And Structures In Devon
A building, or edifice, is an enclosed structure with a roof and walls standing more or less permanently in one place, such as a house or factory (although there's also portable buildings). Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, prestige, and aesthetic reasons. To better understand the term ''building'' compare the list of nonbuilding structures. Buildings serve several societal needs – primarily as shelter from weather, security, living space, privacy, to store belongings, and to comfortably live and work. A building as a shelter represents a physical division of the human habitat (a place of comfort and safety) and the ''outside'' (a place that at times may be harsh and harmful). Ever since the first cave paintings, buildings have also become objects or canvasses of much artistic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediumwave
Medium wave (MW) is the part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band. During the daytime, reception is usually limited to more local stations, though this is dependent on the signal conditions and quality of radio receiver used. Improved signal propagation at night allows the reception of much longer distance signals (within a range of about 2,000 km or 1,200 miles). This can cause increased interference because on most channels multiple transmitters operate simultaneously worldwide. In addition, amplitude modulation (AM) is often more prone to interference by various electronic devices, especially power supplies and computers. Strong transmitters cover larger areas than on the FM broadcast band but require more energy and longer antennas. Digital modes are possible but have not reached momentum yet. MW was the main radio ban ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC Research
BBC Research & Development is the technical research department of the BBC. Function It has responsibility for researching and developing advanced and emerging media technologies for the benefit of the corporation, and wider UK and European media industries, and is also the technical design authority for a number of major technical infrastructure transformation projects for the UK broadcasting industry. Structure BBC R&D is part of the wider BBC Design & Engineering, and is led by Jatin Aythora, Director, Research & Development. In 2011, the North Lab moved into MediaCityUK in Salford along with several other departments of the BBC, whilst the South Lab remained in White City in London. History In April 1930 the Development section of the BBC became the Research Department. The department as it stands today was formed in 1993 from the merger of the BBC Designs Department and the BBC Research Department. From 2006 to 2008 it was known as Research and Innovation but has sin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brookmans Park Transmitting Station
The Brookmans Park transmitting station is a facility for medium wave (MW) broadcasting at Brookmans Park, Hertfordshire, north of London (). The station was built in the 1920s by the BBC as the first of a network of regional dual ("twin wave" was the term then used) transmitter stations, replacing the city-based ones used previously, and this was to cover the Home Counties, London and South East. The station is now owned by Arqiva and transmits BBC Radio 5 Live, talkSPORT, Absolute Radio and Lyca Radio. History The first station, on 842 kHz, (356m) 50 kW, went into service in on 21 October 1929, the second on 1,148 kHz, (261m) initially 30 kW, followed on 9 March 1930. The original antenna configuration for the station was two T-antennas hung from four 200 ft (61m) towers, one T-antenna to the north of the station and the other to the south of the station. Shortly after the commencement of transmissions, the channels were identified by a name den ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loading Coil
A loading coil or load coil is an inductor that is inserted into an electronic circuit to increase its inductance. The term originated in the 19th century for inductors used to prevent signal distortion in long-distance telegraph transmission cables. The term is also used for inductors in radio antennas, or between the antenna and its feedline, to make an electrically short antenna resonant at its operating frequency. The concept of loading coils was discovered by Oliver Heaviside in studying the problem of slow signalling speed of the first transatlantic telegraph cable in the 1860s. He concluded additional inductance was required to prevent amplitude and time delay distortion of the transmitted signal. The mathematical condition for distortion-free transmission is known as the Heaviside condition. Previous telegraph lines were overland or shorter and hence had less delay, and the need for extra inductance was not as great. Submarine communications cables are particularly sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mast Radiator
Mast, MAST or MASt may refer to: Engineering * Mast (sailing), a vertical spar on a sailing ship * Flagmast, a pole for flying a flag * Guyed mast, a structure supported by guy-wires * Mooring mast, a structure for docking an airship * Radio masts and towers , towers that carry antennas * The primary support for a helicopter rotor * The main vertical structure of a forklift truck * Multi-axis shaker table, an automotive test system * Model for assessment of telemedicine, used to assess long-distance medical treatment Biology * Mast (botany), the edible parts of woody plants * Mast Arboretum, at Stephen F. Austin State University in Nacogdoches, Texas * Mast cell, involved in the allergy response * Mast., in botanical naming, the standard author abbreviation for Maxwell T. Masters * Two microtubule-associated serine/threonine-protein kinase enzymes: ** MAST1, an enzyme that in humans is encoded by the ''MAST1'' gene ** MAST2, an enzyme that in humans is encoded by the ''MAST ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcasting
Broadcasting is the distribution (business), distribution of sound, audio or video content to a dispersed audience via any electronic medium (communication), mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a :wikt:one-to-many, one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and radio receiver, receivers. Before this, all forms of electronic communication (early radio, telephone, and telegraph) were wikt:one-to-one, one-to-one, with the message intended for a single recipient. The term ''broadcasting'' evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Channel
The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kanaal, "The Channel"; german: Ärmelkanal, "Sleeve Channel" ( French: ''la Manche;'' also called the British Channel or simply the Channel) is an arm of the Atlantic Ocean that separates Southern England from northern France. It links to the southern part of the North Sea by the Strait of Dover at its northeastern end. It is the busiest shipping area in the world. It is about long and varies in width from at its widest to at its narrowest in the Strait of Dover."English Channel". ''The Columbia Encyclopedia'', 2004. It is the smallest of the shallow seas around the continental shelf of Europe, covering an area of some . The Channel was a key factor in Britain becoming a naval superpower and has been utilised by Britain as a natural def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Telephones And Cables
Standard Telephones and Cables Ltd (later STC plc) was a British manufacturer of telephone, telegraph, radio, telecommunications, and related equipment. During its history, STC invented and developed several groundbreaking new technologies including pulse-code modulation (PCM) and optical fibres. The company was founded in 1883 in London as International Western Electric by the Western Electric Company, shortly after Western Electric became the telephone equipment supplier for the American Telephone and Telegraph Company (AT&T) in the United States. In 1925, Western Electric divested itself of all foreign operations and sold International Western Electric to International Telephone and Telegraph (ITT), in part to thwart antitrust actions by the American government. In mid-1982, STC became an independent company and was listed on the London Stock Exchange; for a time it was a constituent of the FTSE 100 Index. It was bought by Nortel in 1991. History Early days The company was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
