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| {{one source|date=November 2012}}
| | It depends on the quality of the Wordpress theme but even if it's not a professional one you will be able to average 50-60$ EACH link. What I advise you do next is save the backup data file to a remote place like a CD-ROM, external disk drive if you have one or a provider such as Dropbox. One really cool features about this amazing and free wp plugin is that the code it generates is completely portable. Donor oocytes and menopausal pregnancy: Oocyte donation to women of advanced reproductive age: pregnancy results and obstetrical outcomes in patients 45 years and older. This particular wordpress plugin is essential for not only having the capability where you improve your position, but to enhance your organic searches for your website. <br><br> |
| {{Update|date=August 2010}}
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| The '''technology of television''' has changed since its early days using a mechanical system invented by [[Paul Gottlieb Nipkow]] in 1884.
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| ==Elements of a television system==
| | As you know today Word - Press has turn out to be a tremendously popular open source publishing and blogging display place. You may either choose to link only to the top-level category pages or the ones that contain information about your products and services. There are number of web services that offer Word press development across the world. It primarily lays emphasis on improving the search engine results of your website whenever a related query is typed in the search box. This can be done by using a popular layout format and your unique Word - Press design can be achieved in other elements of the blog. <br><br>It is also popular because willing surrogates,as well as egg and sperm donors,are plentiful. s cutthroat competition prevailing in the online space won. If Gandhi was empowered with a blogging system, every event in his life would have been minutely documented so that it could be recounted to the future generations. Thousands of plugins are available in Word - Press plugin's library which makes the task of selecting right set of plugins for your website a very tedious task. Customization of web layout is easy due to the availability of huge selection of templates. <br><br>Google Maps Excellent navigation feature with Google Maps and latitude, for letting people who have access to your account Latitude know exactly where you are. In case you need to hire PHP developers or hire Offshore Code - Igniter development services or you are looking for Word - Press development experts then Mindfire Solutions would be the right choice for a Software Development partner. Exacting subjects in reality must be accumulated in head ahead of planning on your high quality theme. Word - Press is the most popular open source content management system (CMS) in the world today. If you have any sort of concerns concerning where and ways to use [http://www.vws-clan.de/index.php?mod=users&action=view&id=92511 wordpress backup], you could call us at our site. This includes enriching the content with proper key words, tactfully defining the tags and URL. <br><br>As a open source platform Wordpress offers distinctive ready to use themes for free along with custom theme support and easy customization. As a website owner, you can easily manage CMS-based website in a pretty easy and convenient style. Offshore Wordpress development services from a legitimate source caters dedicated and professional services assistance with very simplified yet technically effective development and designing techniques from experienced professional Wordpress developer India. This is because of the customization that works as a keystone for a SEO friendly blogging portal website. The 2010 voting took place from July 7 through August 31, 2010. |
| ''[[File:OTVbelweder-front.jpg|thumb|right|[[Belweder (TV set)|OT-1471 Belweder]], [[People's Republic of Poland|Poland]],'' 1957<br />
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| {{col-begin}}
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| 1. power switch / volume<br />
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| 2. brightness<br />
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| 3. pitch<br />
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| 4. vertical synchro<br />
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| {{col-break}}
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| 5. horizontal synchro<br />
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| 6. contrast<br />
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| 7. channel tuning<br />
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| 8. channel switch
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| {{col-end}}]]
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| The elements of a simple [[Broadcasting|broadcast]] television system are:
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| * An image source. This is the electrical signal representing the visual image, and may be from a [[professional video camera]] in the case of [[live television]], a [[video tape recorder]] for playback of recorded images, or [[telecine]] with a [[flying spot scanner]] for the transfer of [[motion picture]]s to video).
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| * A sound source. This is an electrical signal from a [[microphone]] or from the audio output of a [[video tape recorder]].
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| * A [[transmitter]], which generates [[radio]] signals ([[radio]] waves) and encodes them with picture and sound information.
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| * A [[television antenna]] coupled to the output of the [[transmitter]] for [[broadcasting]] the encoded signals.
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| * A [television antenna to receive the [[Broadcasting|broadcast]] signals.
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| * A receiver (also called a [[Tuner (electronics)|tuner]]), which decodes the picture and sound information from the [[Broadcasting|broadcast]] signals, and whose input is coupled to the antenna of the [[television set]].
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| * A [[display device]], which turns the electrical signals into visual images.
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| * An [[sound|audio]] [[amplifier]] and [[loudspeaker]], which turns electrical signals into sound waves (speech, music, and other sounds) to accompany the images.
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| Practical television systems include equipment for selecting different image sources, mixing images from several sources at once, insertion of pre-recorded video signals, synchronizing signals from many sources, and direct image generation by [[computer]] for such purposes as station identification. The facility for housing such equipment, as well as providing space for stages, sets, offices, etc., is called a [[television studio]], and may be located many miles from the [[transmitter]]. Communication from the studio to the [[transmitter]] is accomplished via a dedicated cable or [[radio]] system.
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| Television signals were originally transmitted exclusively via land-based transmitters. The quality of reception varied greatly, dependent in large part on the location and type of receiving antenna. This led to the proliferation of large rooftop antennas to improve reception in the 1960s, replacing set-top [[Dipole antenna|dipole]] or "rabbit ears" antennas, which however remained popular. [[Rotor (antenna)|Antenna rotors]], set-top controlled [[Servomechanism|servo motors]] to which the mast of the antenna is mounted, to enable rotating the antenna such that it points to the desired transmitter, would also become popular.
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| In most cities today, [[cable television]] providers deliver signals over [[Coaxial cable|coaxial]] or [[Fiber-optic communication|fiber-optic]] cables for a fee. Signals can also be delivered by [[radio]] from [[Satellite television|satellites]] in [[geosynchronous orbit]] and received by [[Parabolic antenna|parabolic dish antennas]], which are comparatively large for [[Analog signal|analog]] signals, but much smaller for [[Digital television|digital]]. Like cable providers, [[satellite television]] providers also require a fee, often less than cable systems. The affordability and convenience of digital satellite reception has led to the proliferation of small dish antennas outside many houses and apartments.
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| [[Digital electronics|Digital]] systems may be inserted anywhere in the chain to provide better image transmission quality, reduction in transmission [[Bandwidth (signal processing)|bandwidth]], special effects, or security of transmission from reception by non-subscribers. A home today might have the choice of receiving analog or [[HDTV]] over the air, analog or digital cable with [[HDTV]] from a [[cable television]] company over [[coaxial cable]], or even from the phone company over [[Fiber-optic communication|fiber optic]] lines. On the road, television can be received by pocket sized televisions, recorded on tape or digital media players, or played back on [[Mobile phone|wireless phones (mobile or "cell" phones)]] over a [[Broadband Internet access|high-speed or "broadband" internet connection]].
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| <!-- Elements of a television system - block diagram here --> | |
| <!-- Image source, camera, film, magnetic tape, exceptionally computer-generated images--> | |
| <!-- Sound source -->
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| <!-- Transmitter, over the air, bandwidth required, antenna, satellite system, cable system, digital encoding, scrambling -->
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| <!-- Receiver, antenna, cable connection, satellite down-converter, digital decode, descramble-->
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| <!-- Display, cathode ray tube, color tube, now LCD, historically mechanical scanned lamp-->
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| <!-- Recorder, analogue magnetic tape, now digital (DVD) -->
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| ==Display technology==
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| {{see|Comparison of display technology|Large-screen television technology|Plasma display|Liquid crystal display television}}
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| [[File:Dv schnittplatz.JPG|thumb|[[Digital video]] equipment in an edit suite]]
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| Thanks to the advances in display technology, there are now several kinds of video displays used in modern TV sets:
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| *'''CRT''' ([[cathode-ray tube]]): The most common screens were direct-view CRTs for up to roughly 100 cm (40 inch) (in 4:3 ratio) and 115 cm (45 inch) (in 16:9 ratio) [[diagonal]]s. These are the least expensive, and are a refined technology that can still provide the best overall picture quality value. As they do not have a fixed [[native resolution]], they are capable of displaying sources with different resolutions at the best possible image quality. The [[frame rate]] or refresh rate of a typical [[NTSC]] format CRT TV is 29.97 Hz, and for the [[PAL]] format, 25 Hz, both are scanned with two fields per frame in an [[Interlaced video|interlace]]d fashion. A typical [[NTSC]] broadcast signal's visible portion has an equivalent resolution of about 640x480 pixels. It actually could be slightly higher than that, but the [[vertical blanking interval]] (VBI), allows other signals to be carried along with the broadcast.
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| *'''[[Rear-projection television|Rear Projection]]''' ('''RPTV'''): Most very large screen TVs (up to 254 cm (100 inch) and beyond) use [[Video projector|projection]] technology. Three types of projection systems are used in projection TVs: CRT-based, [[Liquid crystal display|LCD]]-based, and [[Digital Light Processing|DLP]] (reflective micromirror chip) -based, [[D-ILA]] and [[LCOS]]-based. Projection television has been commercially available since the 1970s, but at that time could not match the image sharpness of the CRT; current models are vastly improved, and offer a cost-effective large-screen display.
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| **A variation is a '''[[video projector]]''', using similar technology, which projects onto a [[Projection screen|screen]]. This is often referred to as "front projection".
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| *'''[[Flat panel display]]''' ([[Liquid crystal display|LCD]] or [[Plasma display|plasma]]): Modern advances have brought [[Flat panel display|flat panels]] to TV that use [[Active-matrix liquid crystal display|active matrix]] LCD or plasma display technology. Flat panel LCDs and plasma displays are as little as 25.4 mm (1 inch) thick and can be hung on a wall like a picture or put over a [[pedestal]]. Some models can also be used as [[Visual display unit|computer monitors]].
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| *'''[[OLED]]''' (organic light-emitting diode) technology has become one of the choices for outdoor video and stadium uses, since the advent of bright [[Light-emitting diode|LEDs]] and driver circuits. OLEDs enable scalable ultra-large flat panel video displays that other technologies are currently not able to match in performance.
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| Each has its pros and cons. Flat panel LCD and plasma displays have a wide viewing angle (around 178 degrees) so they may best suited for a home theatre with a wide seating arrangement. Rear projection screens do not perform well in [[daylight]] or well-lit rooms and so are only suited to darker viewing areas.
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| == Terminology for televisions ==
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| Pixel [[Display resolution|resolution]] is the number of [[pixels]] of one row on a given screen. Before the year 2000 ''horizontal lines of resolution'' was the standard method of measurement for analog video. For example, a VHS VCR might be described as having 250 lines of resolution as measured across a circle circumscribed in the center of the screen (approximately 440 pixels edge-to-edge).
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| A typical resolution of 720×480 and 720x576 means that the television display has 720 pixels across and 480 or 576 pixels on the vertical axis. The higher the resolution on a specified display the sharper the image. Contrast [[ratio]] is a measurement of the range between the lightest and darkest points on the screen.
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| The higher the contrast ratio, the better looking picture there is in terms of richness, deepness, and [[shadow]] detail. The [[brightness]] of a picture measures how vibrant and impacting the colors are. Measured in <math>cd/m^2</math> equivalent to the amount of candles required to power the [[image]].
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| On the other hand, the so-called ''brightness'' and ''contrast'' adjustment controls on televisions and monitors are traditionally used to control different aspects of the picture display. The brightness control shifts the black level, affecting the image intensity or brightness, while the contrast control adjusts the contrast range of the image.<ref>John Watkinson, ''Convergence in Broadcast and Communications Media: The Fundamentals of Audio, Video, Data'', Focal Press, 2001, ISBN 0-240-51509-9</ref>
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| ==Transmission band==
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| There are various bands on which televisions operate depending upon the country. The [[VHF]] and [[UHF]] signals in bands III to V are generally used. Lower frequencies do not have enough [[Bandwidth (signal processing)|bandwidth]] available for television. Although the [[BBC]] initially used Band I VHF at 45 MHz, this frequency is (in the UK) no longer in use for this purpose. Band II is used for FM radio transmissions. Higher frequencies behave more like light and do not penetrate buildings or travel around obstructions well enough to be used in a conventional broadcast TV system, so they are generally only used for [[MMDS]] and [[satellite television]], which uses frequencies from 2 to 12 GHz. TV systems in most countries relay the video as an AM ([[amplitude-modulation]]) signal and the sound as an FM ([[frequency-modulation]]) signal. An exception is [[France]], where the sound is AM.
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| ==Aspect ratios==
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| '''[[Aspect ratio (image)|Aspect ratio]]''' refers to the ratio of the horizontal to vertical measurements of a television's picture. Mechanically scanned television as first demonstrated by [[John Logie Baird]] in 1926 used a 7:3 vertical aspect ratio, oriented for the head and shoulders of a single person in close-up.
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| Most of the early electronic TV systems, from the mid-1930s onward, shared the same [[aspect ratio (image)|aspect ratio]] of 4:3 which was chosen to match the [[Academy ratio|Academy Ratio]] used in cinema films at the time. This ratio was also square enough to be conveniently viewed on round [[cathode ray tube|cathode-ray tubes]] (CRTs), which were all that could be produced given the [[manufacturing]] [[technology]] of the time. (Today's CRT technology allows the manufacture of much wider tubes, and the flat-screen technologies which are becoming steadily more popular have no technical aspect ratio limitations at all.) The [[BBC]]'s television service used a more squarish [http://tcc.members.beeb.net/tchistory.html 5:4] ratio from 1936 to [http://www.pembers.freeserve.co.uk/Test-Cards/Test-Card-Technical.html#Aspect-Ratio 3 April 1950], when it too switched to a 4:3 ratio. This did not present significant problems, as most sets at the time used round tubes which were easily adjusted to the 4:3 ratio when the transmissions changed.
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| [[File:Hd tv samsung LE26R41BD.jpg|thumb|left|A [[Samsung Electronics|Samsung]] LE26R41BD [[High-definition television|HDTV]]]]
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| In the early 1950s, [[movie studio]]s moved towards [[widescreen]] aspect ratios such as [[CinemaScope]] in an effort to distance their product from television. Although this was initially just a [[gimmick]], widescreen is still the format of choice today and 4:3 aspect ratio movies are rare.
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| Yet the various television systems were not originally designed to be compatible with film at all. Traditional, narrow-screen movies are projected onto a television camera either so that the top of the screens line up to show facial features, or, for films with subtitles, the bottoms. What this means is that filmed newspapers or long captions filling the screen for explanation are cut off at each end. Similarly, while the frame rate of sound films is 24 per second, the screen scanning rate of the NTSC is 29.97 [[Hertz|Hz]] (per second), which requires a complex scanning schedule. That of PAL and SECAM are 50 Hz, which means that films are shortened (and the sound is offkey) by scanning each frame twice for 25 per second.
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| The switch to [[digital television]] systems has been used as an opportunity to change the standard television picture format from the old ratio of 4:3 (1.33:1) to an aspect ratio of 16:9 (approximately 1.78:1). This enables TV to get closer to the aspect ratio of modern widescreen [[film|movies]], which range from 1.66:1 through 1.85:1 to 2.35:1. There are two methods for transporting widescreen content, the most common of which uses what is called [[full screen anamorphic|anamorphic widescreen]] format. This format is very similar to the technique used to fit a widescreen movie frame inside a 1.33:1 35 mm film frame. The image is compressed horizontally when recorded, then expanded again when played back. The anamorphic widescreen 16:9 format was first introduced via European [[PALplus]] television broadcasts and then later on "widescreen" Laser Discs and [[DVD]]s; the [[ATSC Standards|ATSC]] [[High-definition television|HDTV]] system uses straight widescreen format, no horizontal compression or expansion is used.
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| Recently "widescreen" has spread from television to computing where both [[desktop computer|desktop]] and [[laptop]] computers are commonly equipped with widescreen displays. There are some complaints about distortions of movie picture ratio due to some DVD playback software not taking account of aspect ratios; but this may subside as the DVD playback software matures. Furthermore, computer and laptop widescreen displays are in the 16:10 aspect ratio both physically in size and in pixel counts, and not in 16:9 of consumer televisions, leading to further complexity. This was a result of widescreen computer display engineers' assumption that people viewing 16:9 content on their computer would prefer that an area of the screen be reserved for playback controls, [[subtitles]] or their Taskbar, as opposed to viewing content full-screen.
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| ===Aspect ratio incompatibility===
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| The television industry's changing of [[Aspect ratio (image)|aspect ratios]] is not without difficulties, and can present a considerable problem.
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| Displaying a widescreen aspect (rectangular) image on a conventional aspect (square or 4:3) display can be shown:
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| *in "[[letterbox]]" format, with black horizontal bars at the top and bottom
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| *with part of the image being cropped, usually the extreme left and right of the image being cut off (or in "[[pan and scan]]", parts selected by an operator or a viewer)
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| *with the image horizontally compressed
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| A conventional aspect (square or 4:3) image on a widescreen aspect (rectangular with longer horizon) display can be shown:
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| *in "[[pillar box (film)|pillar box]]" format, with black vertical bars to the left and right
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| *with upper and lower portions of the image cut off (or in "tilt and scan", parts selected by an operator)
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| *with the image vertically compressed
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| A common compromise is to shoot or create material at an aspect ratio of 14:9, and to lose some image at each side for 4:3 presentation, and some image at top and bottom for 16:9 presentation. In recent years, the cinematographic process known as [[Super 35]] (championed by [[James Cameron]]) has been used to film a number of major movies such as [[Titanic (1997 film)|''Titanic'']], ''[[Legally Blonde]]'', ''[[Austin Powers (film series)|Austin Powers]]'', and ''[[Crouching Tiger, Hidden Dragon]]''. This process results in a camera-negative which can then be used to create both wide-screen theatrical prints, and standard "[[Fullscreen (cinema)|full screen]]" releases for television/VHS/DVD which avoid the need for either "[[letterbox]]ing" or the severe loss of information caused by conventional "[[pan-and-scan]]" cropping.
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| == Sound ==
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| {{further2|[[NICAM]], [[Multichannel television sound|MTS]], and [[Zweikanalton]]}}
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| == Data ==
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| {{further2|[[Teletext]]}}
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| == The end of analog television broadcasting ==
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| {{main|Digital switchover}}
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| === NTSC ===
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| {{update|section|date=November 2010}}
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| In North America, the basic signal standards since 1941 had been compatible enough in 2007 that even the oldest monochrome televisions could still receive color broadcasts. However, the United States Congress passed a law which required the cessation of all conventional television broadcast signals by February 2009. After that date all [[NTSC]] standard televisions with analog-only tuners went dark unless fitted with a digital [[ATSC tuner]], and the spectrum previously occupied by those analog channels was auctioned off by the United States' Federal Communications Commission for other uses.
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| === PAL and SECAM ===
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| [[PAL]] and [[SECAM]] are expected not to be broadcast in Europe and Eurasia by the mid-2020s. PAL-M may have a similar decommissioning timeline.
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| The [[European Union]] has recommended its members to close down analogue terrestrial television by 2012. Luxembourg and the Netherlands already completed their closedowns in 2006, and Finland and Sweden closed down their analogue broadcasts in 2007. | |
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| Britain started its digital switch in October 2007. At 2AM on Wednesday 17 October 2007, the BBC2 transmitter covering the Whitehaven and Copeland areas (NW England) was disabled. The remaining four analogue channels ceased broadcasting shortly after. The original five channels are now available only in digital form, alongside approximately 15 additional free-to-air channels.
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| == New developments ==
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| {{col-begin}}
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| {{col-break}}
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| * [[3D television]]
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| * [[Ambilight]]
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| * [[Broadcast flag]]
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| * [[CableCARD]]
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| * [[Digital Light Processing]] (DLP)
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| * [[Digital Rights Management]] (DRM)
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| * [[Digital television]] (DTV)
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| * [[Digital Video Recorder]]s (DVR)
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| * [[Direct Broadcast Satellite]] TV (DBS)
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| * [[DVD]] and [[HD DVD]] standards
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| * [[Blu-ray Disc]]
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| * [[Flat panel display]]
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| * [[Flicker-free]] (100 Hz or 120 Hz, depending on country)
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| * [[High Definition TV]] (HDTV)
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| * [[High-Definition Multimedia Interface]] (HDMI)
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| * [[IPTV]] also known as [[Internet television]] (IPTV)
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| * [[Laser TV]] display technology
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| {{col-break}}
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| * [[Liquid crystal display television]] (LCD)
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| * [[Mirror TV]]
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| * [[OLED TV]] - Roll up TV (using organic light-emitting diodes)
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| * [[P2PTV]]
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| * [[Pay-per-view]]
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| * [[Personal video recorder]]s (PVR)
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| * [[Picture-in-picture]] (PiP)
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| * [[Pixelplus]]
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| * [[Placeshifting]]
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| * [[Plasma display]]
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| * [[Remote control]]s
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| * [[Surface-conduction electron-emitter display]] (SED) display technology
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| * The [[Slingbox]]
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| * [[Time shifting]]
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| * [[Video on-demand]] (VOD)
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| * [[Ultra High Definition Television]] (UHDTV)
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| * [[Web TV]]
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| {{col-break}}
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| [[File:Long screen television.jpg|thumb|right|A long screen television in Korea.]]
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| {{col-end}}
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| == Exterior designs ==
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| In the early days of television, cabinets were made of wood grain (often simulated particularly in the later years), however, they went out of style in the 1980s. Up until the late 1970s, console TV/Hi Fi's were common. These were large (about 6' wide by 4' high) wooden cabinets containing a television, speakers, [[radio]] and a [[phonograph|turntable]].
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| ==See also==
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| * [[Broadcast safe]]
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| * [[Electronic waste]]
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| * [[History of display technology]]
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| * [[History of television]]
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| ==References==
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| {{reflist}}
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| <br>
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| {{Video formats}}
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| {{Telecommunications}}
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| {{Use dmy dates|date=October 2010}}
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| {{DEFAULTSORT:Technology Of Television}}
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| [[Category:Television technology|*]]
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| [[Category:Media technology]]
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| [[Category:Television terminology]]
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| [[Category:History of television]]
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