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CCIR System K
CCIR System K is an analog broadcast television system used in countries that adopted CCIR System D on VHF, and identical to it in most respects.https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BT.624-4-1990-PDF-E.pdf Used only for UHF frequencies, its paired with SECAM or PAL color systems. Specifications Some of the important specs are listed below. Television channels were arranged as follows: System K1 French overseas departments and territories used a variation named System K1 for broadcast in VHF. UHF channels were similar to K. See also *Broadcast television systems *Television transmitter A television transmitter is a transmitter that is used for terrestrial (over-the-air) television broadcasting. It is an electronic device that radiates radio waves that carry a video signal representing moving images, along with a synchronized ... * Transposer Notes and references External links World Analogue Television Standards and Waveforms {{Analogue TV tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comité Consultatif International Pour La Radio
The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communications. Its role is to manage the international radio-frequency spectrum and satellite orbit resources and to develop standards for radiocommunication systems with the objective of ensuring the effective use of the spectrum. ITU is required, according to its constitution, to allocate spectrum and register frequency allocation, orbital positions and other parameters of satellites, “in order to avoid harmful interference between radio stations of different countries”. The international spectrum management system is therefore based on regulatory procedures for frequency coordination, notification and registration. ITU-R has a permanent secretariat, the Radiocommunication Bureau, based at the ITU HQ in Geneva, Switzerland. The electeDirector of the Bureauis Mr. Mario Maniewicz; he was first elected by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Television Systems
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 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 2010s. 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 spectrum (ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CCIR System D
CCIR System D is an analog broadcast television system used in the Commonwealth of Independent States, parts of Eastern Europe and People's Republic of China. Initially known as the I.B.T.O. 625-line system this was the first 625-line system, developed by Mark Iosifovich Krivosheev in 1948, and later associated with the SECAM and PAL color systems. Used on VHF only in most countries, it's usually combined with system K on UHF. In China it is used for both VHF and UHF. Specifications Some of the important specs are listed below: Television channels were arranged as follows: * The original assignments of channels 25 to 57 were 2 MHz higher in frequency until c.1984. Channels 58 to 62 were deleted at this time. See also *Broadcast television systems *Television transmitter *Transposer In broadcasting, a transposer or translator is a device in or beyond the service area of a radio or television station transmitter that rebroadcasts signals to receivers whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SECAM
SECAM, also written SÉCAM (, ''Séquentiel de couleur à mémoire'', French for ''color sequential with memory''), is an analog color television system that was used in France, some parts of Europe and Africa, and Russia. It was one of three major analog color television standards, the others being PAL and NTSC. This page primarily discusses the SECAM colour encoding system. The articles on broadcast television systems and analog television further describe frame rates, image resolution, and audio modulation. SECAM video is composite video because the luminance (luma, monochrome image) and chrominance (chroma, color applied to the monochrome image) are transmitted together as one signal. All the countries using SECAM are currently in the process of conversion, or have already converted to Digital Video Broadcasting (DVB), the new pan-European standard for digital television. SECAM remained a major standard into the 2000s. History Development of SECAM predates PAL, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Television Channel
A television channel is a terrestrial frequency or virtual number over which a television station or television network is distributed. For example, in North America, "channel 2" refers to the terrestrial or cable band of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video ( VSB) and 59.75 MHz for analog audio ( FM), or 55.31 MHz for digital ATSC ( 8VSB). Channels may be shared by many different television stations or cable-distributed channels depending on the location and service provider Depending on the multinational bandplan for a given regional n, analog television channels are typically 6, 7, or 8 MHz in bandwidth, and therefore television channel frequencies vary as well. Channel numbering is also different. Digital terrestrial television channels are the same as their analog predecessors for legacy reasons, however through multiplexing, each physical radio frequency (RF) channel can carry several digital subcha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VHF Usage
Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF). VHF radio waves propagate mainly by line-of-sight, so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the visual horizon out to about 160 km (100 miles). Common uses for radio waves in the VHF band are Digital Audio Broadcasting (DAB) and FM radio broadcasting, television broadcasting, two-way land mobile radio systems (emergency, business, private use and military), long range data communication up to several tens of kilometers with radio modems, amateur radio, and marine communications. Air traffic control communications and air navigation systems (e.g. VOR and ILS) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Overseas Departments And Territories
Overseas France (french: France d'outre-mer) consists of 13 French-administered territories outside Europe, mostly the remains of the French colonial empire that chose to remain a part of the French state under various statuses after decolonization. They are part of the European Union. This collective name is used in everyday life in France but is not an administrative designation in its own right. Instead, the five overseas regions have exactly the same administrative status as the metropolitan regions; the five overseas collectivities are semi-autonomous; and New Caledonia is an autonomous territory. Overseas France includes island territories in the Atlantic, Pacific and Indian Oceans, French Guiana on the South American continent, and several peri-Antarctic islands as well as a claim in Antarctica. Excluding the district of Adélie Land, where French sovereignty is effective ''de jure'' by French law, but where the French exclusive claim on this part of Antarctica is f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Television Transmitter
A television transmitter is a transmitter that is used for terrestrial (over-the-air) television broadcasting. It is an electronic device that radiates radio waves that carry a video signal representing moving images, along with a synchronized audio channel, which is received by television receivers ('televisions' or 'TVs') belonging to a public audience, which display the image on a screen. A television transmitter, together with the broadcast studio which originates the content, is called a television station. Television transmitters must be licensed by governments, and are restricted to a certain frequency channel and power level. They transmit on frequency channels in the VHF and UHF bands. Since radio waves of these frequencies travel by line of sight, they are limited by the horizon to reception distances of 40–60 miles depending on the height of transmitter station. Television transmitters use one of two different technologies: ''analog'', in which the picture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposer
In broadcasting, a transposer or translator is a device in or beyond the service area of a radio or television station transmitter that rebroadcasts signals to receivers which can’t properly receive the signals of the transmitter because of a physical obstruction (like a hill). A translator receives the signals of the transmitter and rebroadcasts the signals to the area of poor reception. Sometimes the translator is also called a ''relay transmitter'', ''rebroadcast transmitter'' or ''transposer.'' Since translators are used to cover a small shadowed area, their output powers are usually lower than that of the radio or television station transmitters feeding them. Physical obstruction Reception of RF signals is sensitive to the size of obstruction in the path between the transmitter and the receiver. Generally speaking, if the size exceeds the wavelength the reception is interrupted. Since the wavelength is inversely proportional to frequency, it follows than that the higher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-R Recommendations
The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communications. Its role is to manage the international radio-frequency spectrum and satellite orbit resources and to develop standards for radiocommunication systems with the objective of ensuring the effective use of the spectrum. ITU is required, according to its constitution, to allocate spectrum and register frequency allocation, orbital positions and other parameters of satellites, “in order to avoid harmful interference between radio stations of different countries”. The international spectrum management system is therefore based on regulatory procedures for frequency coordination, notification and registration. ITU-R has a permanent secretariat, the Radiocommunication Bureau, based at the ITU HQ in Geneva, Switzerland. The electeDirector of the Bureauis Mr. Mario Maniewicz; he was first elected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Television Technology
Large-screen television technology (colloquially big-screen TV) developed rapidly in the late 1990s and 2000s. Prior to the development of thin-screen technologies, rear-projection television was standard for larger displays, and jumbotron, a non-projection video display technology, was used at stadiums and concerts. Various thin-screen technologies are being developed, but only liquid crystal display (LCD), plasma display (PDP) and Digital Light Processing (DLP) have been publicly released. Recent technologies like organic light-emitting diode (OLED) as well as not-yet-released technologies like surface-conduction electron-emitter display (SED) or field emission display (FED) are in development to replace earlier flat-screen technologies in picture quality. Large-screen technologies have almost completely displaced cathode-ray tubes (CRT) in television sales due to the necessary bulkiness of cathode-ray tubes. The diagonal screen size of a CRT television is limited to abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Formats
Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems which, in turn, were replaced by flat panel displays of several types. Video systems vary in display resolution, aspect ratio, refresh rate, color capabilities and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcast, magnetic tape, optical discs, computer files, and network streaming. History Analog video Video technology was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) television systems, but several new technologies for video display devices have since been invented. Video was originally exclusively a live technology. Charles Ginsburg led an Ampex research team developing one of the first practical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
