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405-line
The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting. The number of television lines influences the image resolution, or quality of the picture. It was introduced with the BBC Television Service in 1936, suspended for the duration of World War II, and remained in operation in the UK until 1985. It was also used between 1961 and 1982 in Ireland, as well as from 1957 to 1973 for the Rediffusion Television cable service in Hong Kong. 405-line was approved as System A in the CCIR assignment of broadcast systems. Sometimes called the Marconi-EMI system, it was developed in 1934 by the EMI Research Team led by Isaac Shoenberg. The figure of 405 lines had been chosen following discussions over Sunday lunch at the home of Alan Blumlein. The system used interlacing; EMI had been experimenting with a 243-line all-electronic interlaced system since 1933. In the 405 system the scannin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Television System
Broadcast television systems (or terrestrial television systems outside the US and Canada) are the encoding or formatting systems for the transmission and reception of terrestrial television signals. Analog television systems were standardized by the International Telecommunication Union (ITU) in 1961, with each system designated by a letter ( A- N) in combination with the color standard used (NTSC, PAL or SECAM) - for example PAL-B, NTSC-M, etc.). These analog systems for TV broadcasting dominated until the 2000s. With the introduction of digital terrestrial television (DTT), they were replaced by four main systems in use around the world: ATSC, DVB, ISDB and DTMB. Analog television systems Every analog television system bar one began as a black-and-white system. Each country, faced with local political, technical, and economic issues, adopted a color television standard which was grafted onto an existing monochrome system such as CCIR System M, using gaps in the video ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CCIR System A
CCIR System A was the 405-line analog broadcast television system adopted in the UK and Ireland. System A service started in 1936 and was discontinued in 1982 in Ireland and 1985 in Britain. Specifications Some of the important specs are listed below. * Frame rate: 25 Hz * Interlace: 2/1 * Field rate: 50 Hz * Lines per frame: 405 * Line rate: 10.125 kHz * Visual bandwidth: 3 MHz * Vision modulation: AC3 positive * Preemphasis: none * Sound modulation: A3 * Sound offset: -3.5 MHz * Channel bandwidth: 5 MHz A frame is the total picture. The frame rate is the number of pictures displayed in one second. But each frame is actually scanned twice interleaving odd and even lines. Each scan is known as a field (odd and even fields.) So field rate is twice the frame rate. In each frame there are 405 lines (or 202.5 lines in a field.) So the line rate (line frequency) is 405 times the frame frequency or 405×25=10,125 Hz. The video bandwidth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Shoenberg
Sir Isaac Shoenberg (1 March 1880 – 25 January 1963) was a British electronic engineer born in Belarus who was best known for his role in the history of television. He was the head of the EMI research team that developed the 405-line (Marconi-EMI system), the first fully electronic television system to be used in regular broadcasting when it was introduced with the BBC Television Service in 1936. It was later adopted by other TV organizations around the world. As the head of research at EMI, Schoenberg was Alan Blumlein's supervisor when Blumlein invented stereophonic sound in 1931. Schoenberg was awarded the IET Faraday Medal by the British Institution of Electrical Engineers in 1954 and was knighted by Queen Elizabeth II in 1962. Biography Shoenberg was born on 1 March 1880 to Jewish parents in Pinsk, Imperial Russia (now Belarus) and studied mathematics and electricity at Kiev Polytechnic Institute. He met his wife, Esther Aisenstein, while they both studied at Kiev. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandra Palace
Alexandra Palace is an entertainment and sports venue in North London, situated between Wood Green and Muswell Hill in the London Borough of Haringey. A listed building, Grade II listed building, it is built on the site of Tottenham Wood and the later Tottenham Wood Farm. It was designed by John Johnson (architect, born 1807), John Johnson and Alfred Meeson. It opened in 1873 but following a fire two weeks after its opening, was rebuilt by Johnson. It was intended as "the People's Palace" and as such it is often referred to by the nickname "Ally Pally". At first a private venture, in 1900, the owners planned to sell it and Alexandra Park, London, Alexandra Park for development. A group of neighbouring local authorities managed to acquire it. An Act of Parliament created the Alexandra Palace and Park Trust. The Act required the trustees to maintain the building and park and make them available for the free use and recreation of the public forever. The present trustee is the Londo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
625 Lines
625-line (or CCIR 625/50) is a late 1940s European analog standard-definition television resolution standard. It consists of a 625-line raster, with 576 lines carrying the visible image at 25 interlaced frames per second. It was eventually adopted by countries using 50 Hz utility frequency as regular TV broadcasts resumed after World War II. With the introduction of color television in the 1960s, it became associated with the PAL and SECAM analog color systems. A similar 525-line system was adopted by countries using 60 Hz utility frequency (like the US). Other systems, like 375-line, 405-line, 441-line, 455-line and 819-line existed, but became outdated or had limited adoption. The modern standard-definition digital video resolution 576i is equivalent and can be used to digitize an analogue 625-line TV signal, or to generate a 625-line compatible analog signal. History At the CCIR Stockholm Conference in July 1948 a first 625-line system with an 8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Logie Baird
John Logie Baird (; 13 August 188814 June 1946) was a Scottish inventor, electrical engineer, and innovator who demonstrated the world's first mechanical Mechanical television, television system on 26 January 1926. He went on to invent the first publicly demonstrated colour television system and the first viable purely electronic Color television, 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. In 2006, Baird was named as one of the 10 greatest Scottish scientists in history, having been listed in the National Library of Scotland's 'Scottish Science Hall of Fame'. In 2015, he was inducted into the Scottish Engineering Hall of Fame. In 2017, IEEE unveiled a bronze street plaque at 22 Frith Street (Bar I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC One
BBC One is a British free-to-air public broadcast television channel owned and operated by the BBC. It is the corporation's oldest and flagship channel, and is known for broadcasting mainstream programming, which includes BBC News television bulletins, primetime drama and entertainment, and live BBC Sport events. The channel was launched on 2 November 1936 under the name BBC Television Service, which was the world's first regular television service with a high level of image resolution. It was renamed BBC TV in 1960 and used this name until the launch of the second BBC channel, BBC2, in 1964. The main channel then became known as BBC1. The channel adopted the current spelling of BBC One in 1997. The channel's annual budget for 2012–2013 was £1.14 billion. It is funded by the television licence fee together with the BBC's other domestic television stations and shows uninterrupted programming without commercial advertising. The television channel had the highest reach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Television
Mechanical television or mechanical scan television is an obsolete television system that relies on a mechanism (engineering), mechanical scanning device, such as a rotating disk with holes in it or a rotating mirror drum, to scan the scene and generate the video signal, and a similar mechanical device at the receiver to display the picture. This contrasts with vacuum tube electronic television technology, using electron beam scanning methods, for example in cathode-ray tube (CRT) televisions. Subsequently, modern solid-state liquid-crystal displays (LCD) and LED displays are now used to create and display television pictures. Mechanical scanning methods were used in the earliest experimental television systems in the 1920s and 1930s. One of the first experimental wireless television transmissions was by Scottish inventor John Logie Baird on October 2, 1925, in London. By 1928 many radio stations were broadcasting experimental television programs using mechanical systems. Howeve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1936 In Television
The year 1936 in television involved some significant events. Below is a list of television-related events during 1936. __TOC__ Events *July 7 – At David Sarnoff's request for an experiment of RCA's electronic television technology, NBC's first attempt at actual programming is a 30-minute variety show featuring speeches, dance ensembles, monologues, vocal numbers, and film clips. It is shown to 225 of RCA's licensees on 22 centimeter screens, 343 lines per picture, 30 pictures per second. *August – 72 hours of medium-definition (180-line) television broadcasts of the 1936 Summer Olympics in Berlin are seen by approximately 150,000 people in public viewing rooms in Berlin and Potsdam. *November 2 – The first regular high-definition (then defined as at least 200 lines) television service from the BBC, based at Alexandra Palace in London, officially begins broadcasting (after test transmissions began in August). The service alternates on a weekly basis between John Logie Bai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alan Blumlein
Alan Dower Blumlein (; 29 June 1903 – 7 June 1942) was an English electronics engineer, notable for his many inventions in telecommunications, sound recording, stereophonic sound, television and radar. He received 128 patents and was considered one of the most significant engineers and inventors of his time. He died during World War II, on 7 June 1942, aged 38, during the secret trial of an H2S airborne radar system then under development, when all on board the Halifax bomber in which he was flying were killed when it crashed at Welsh Bicknor in Herefordshire. Early life Alan Dower Blumlein was born on 29 June 1903 in Hampstead, London. His father, Semmy Blumlein, was a German-born naturalised British subject. Semmy was the son of Joseph Blumlein, a German of Jewish descent, and Philippine Hellmann, a French woman of German descent.Semmy Blumlein's father, Joseph B. Blumlein was Jewish, ''see Burns, p. 2'' Alan's mother, Jessie Dower, was Scottish, daughter of William Dow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scan Line
A scan line (also scanline) is one line, or row, in a raster scanning pattern, such as a line of video on a cathode-ray tube (CRT) display of a television set or computer monitor. On CRT screens the horizontal scan lines are visually discernible, even when viewed from a distance, as alternating colored lines and black lines, especially when a progressive scan signal with below maximum vertical resolution is displayed. This is sometimes used today as a visual effect in computer graphics. The term is used, by analogy, for a single row of pixels in a raster graphics image. Scan lines are important in representations of image data, because many image file formats have special rules for data at the end of a scan line. For example, there may be a rule that each scan line starts on a particular boundary (such as a byte or word; see for example BMP file format). This means that even otherwise compatible raster data may need to be analyzed at the level of scan lines in order to conver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monochrome
A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochromatic light refers to electromagnetic radiation that contains a narrow band of wavelengths, which is a distinct concept. Application Of an image, the term monochrome is usually taken to mean the same as black and white or, more likely, grayscale, but may also be used to refer to other combinations containing only tones of a single color, such as green-and-white or green-and-red. It may also refer to sepia displaying tones from light tan to dark brown or cyanotype ("blueprint") images, and early photographic methods such as daguerreotypes, ambrotypes, and tintypes, each of which may be used to produce a monochromatic image. In computing, monochrome has two meanings: * it may mean having only one color which is either on or off (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
