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interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Televisi%C3%B3_electromec%C3%A0nica" title="Televisió electromecànica – Catalan" lang="ca" hreflang="ca" data-title="Televisió electromecànica" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Mechanisches_Fernsehen" title="Mechanisches Fernsehen – German" lang="de" hreflang="de" data-title="Mechanisches Fernsehen" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Televisi%C3%B3n_electromec%C3%A1nica" title="Televisión electromecánica – Spanish" lang="es" hreflang="es" data-title="Televisión electromecánica" data-language-autonym="Español" data-language-local-name="Spanish" 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class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Television that relies on a scanning device to display images</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"Televisor" redirects here. Not to be confused with a <a href="/wiki/Television_set" title="Television set">television set</a>, called a "televisor" in several languages.</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Science_and_Invention_Television_1928.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Science_and_Invention_Television_1928.jpg/370px-Science_and_Invention_Television_1928.jpg" decoding="async" width="370" height="206" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Science_and_Invention_Television_1928.jpg/555px-Science_and_Invention_Television_1928.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Science_and_Invention_Television_1928.jpg/740px-Science_and_Invention_Television_1928.jpg 2x" data-file-width="1138" data-file-height="633" /></a><figcaption>Watching a homemade mechanical-scan television receiver in 1928. The "televisor" (right) which produces the picture uses a spinning metal disk with a series of holes in it, called a <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a>, in front of a <a href="/wiki/Neon_lamp" title="Neon lamp">neon lamp</a>. Each hole in the disk passing in front of the lamp produces a scan line which makes up the image. The video signal from the television receiver unit (left) is applied to the neon lamp, causing its brightness to vary with the brightness of the image at each point. This system produced a dim orange image 1.5 inches (3.8 cm) square, with 48 scan lines, at a frame rate of 7.5 frames per second.</figcaption></figure> <p><b>Mechanical television</b> or <b>mechanical scan television</b> is an obsolete <a href="/wiki/Television" title="Television">television</a> system that relies on a <a href="/wiki/Mechanism_(engineering)" title="Mechanism (engineering)">mechanical</a> scanning device, such as a rotating disk with holes in it or a rotating mirror drum, to scan the scene and generate the <a href="/wiki/Video" title="Video">video</a> signal, and a similar mechanical device at the receiver to display the picture. This contrasts with <a href="/wiki/Vacuum_tube" title="Vacuum tube">vacuum tube</a> electronic television technology, using <a href="/wiki/Electron_beam" class="mw-redirect" title="Electron beam">electron beam</a> scanning methods, for example in <a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">cathode-ray tube</a> (CRT) televisions. Subsequently, modern solid-state <a href="/wiki/Liquid-crystal_display" title="Liquid-crystal display">liquid-crystal displays</a> (LCD) and <a href="/wiki/LED_display" title="LED display">LED displays</a> are now used to create and display television pictures. </p><p>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 <a href="/wiki/John_Logie_Baird" title="John Logie Baird">John Logie Baird</a> on October 2, 1925, in London. By 1928 many radio stations were broadcasting experimental television programs using mechanical systems. However the technology never produced images of sufficient quality to become popular with the public. Mechanical-scan systems were largely superseded by electronic-scan technology in the mid-1930s, which was used in the first commercially successful television broadcasts which began in the late 1930s. In the U.S., experimental stations such as <a href="/wiki/W2XAB" class="mw-redirect" title="W2XAB">W2XAB</a> in New York City began broadcasting mechanical television programs in 1931 but discontinued operations on February 20, 1933, until returning with an all-electronic system in 1939. </p><p>A mechanical television receiver was also called a <b>televisor</b>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/History_of_television" title="History of television">History of television</a></div> <div class="mw-heading mw-heading3"><h3 id="Early_research">Early research</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=2" title="Edit section: Early research"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first mechanical raster scanning techniques were developed in the 19th century for <a href="/wiki/Facsimile" title="Facsimile">facsimile</a>, the transmission of still images by wire. <a href="/wiki/Alexander_Bain_(inventor)" title="Alexander Bain (inventor)">Alexander Bain</a> introduced the facsimile machine in 1843 to 1846. <a href="/wiki/Frederick_Bakewell" title="Frederick Bakewell">Frederick Bakewell</a> demonstrated a working laboratory version in 1851. The first practical facsimile system, working on telegraph lines, was developed and put into service by <a href="/wiki/Giovanni_Caselli" title="Giovanni Caselli">Giovanni Caselli</a> from 1856 onward.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Willoughby_Smith" title="Willoughby Smith">Willoughby Smith</a> discovered the <a href="/wiki/Photoconductivity" title="Photoconductivity">photoconductivity</a> of the element <a href="/wiki/Selenium" title="Selenium">selenium</a> in 1873, laying the groundwork for the <a href="/wiki/Selenium_cell" class="mw-redirect" title="Selenium cell">selenium cell</a> which was used as a pickup in most mechanical scan systems. </p><p>In 1885, <a href="/wiki/Henry_Sutton_(inventor)" title="Henry Sutton (inventor)">Henry Sutton</a> in <a href="/wiki/Ballarat,_Australia" class="mw-redirect" title="Ballarat, Australia">Ballarat, Australia</a> designed what he called a <a href="/wiki/Telephane" class="mw-redirect" title="Telephane">telephane</a> for transmission of images via telegraph wires, based on the <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow spinning disk</a> system, <a href="/wiki/Resistive_opto-isolator#History" title="Resistive opto-isolator">selenium photocell</a>, <a href="/wiki/Nicol_prism" title="Nicol prism">Nicol prisms</a> and <a href="/wiki/Kerr_effect" title="Kerr effect">Kerr effect</a> cell.<sup id="cite_ref-Withers_4-0" class="reference"><a href="#cite_note-Withers-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 319">: 319 </span></sup> Sutton's design was published internationally in 1890.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> An account of its use to transmit and preserve a still image was published in the <a href="/wiki/The_Washington_Star" title="The Washington Star">Evening Star</a> in Washington in 1896.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Ernst_Ruhmer_demonstrating_simple_television_system_(1909).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/91/Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg/220px-Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg" decoding="async" width="220" height="166" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/91/Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg/330px-Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/91/Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg/440px-Ernst_Ruhmer_demonstrating_simple_television_system_%281909%29.jpg 2x" data-file-width="674" data-file-height="510" /></a><figcaption>Ernst Ruhmer demonstrating his experimental television system, which was capable of transmitting 5×5 <a href="/wiki/Pixel" title="Pixel">pixel</a> images of simple shapes over telephone lines, using a 25-element selenium cell receiver (1909)<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>The first demonstration of the <i>instantaneous</i> transmission of images was made by a German physicist, <a href="/wiki/Ernst_Ruhmer" title="Ernst Ruhmer">Ernst Ruhmer</a>, who arranged 25 selenium cells as the picture elements for a television receiver. In late 1909 he successfully demonstrated in Belgium the transmission of simple images over a telephone wire from the <a href="/wiki/Palais_de_Justice,_Brussels" class="mw-redirect" title="Palais de Justice, Brussels">Palace of Justice</a> at Brussels to the city of Liege, a distance of 115 km (71 mi). This demonstration was described at the time as "the world's first working model of television apparatus".<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> The limited number of elements meant his device was only capable of representing simple geometric shapes, and the cost was very high; at a price of £15 (US$45) per selenium cell, he estimated that a 4,000 cell system would cost £60,000 (US$180,000), and a 10,000 cell mechanism capable of reproducing "a scene or event requiring the background of a landscape" would cost £150,000 (US$450,000). Ruhmer expressed the hope that the 1910 Brussels <span title="French-language text"><i lang="fr"><a href="/wiki/Brussels_International_1910" class="mw-redirect" title="Brussels International 1910">Exposition Universelle et Internationale</a></i></span> would sponsor the construction of an advanced device with significantly more cells, as a showcase for the exposition. However, the estimated expense of £250,000 (US$750,000) proved to be too high.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>The publicity generated by Ruhmer's demonstration spurred two French scientists, Georges Rignoux and A. Fournier in Paris, to announce similar research that they had been conducting.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> A matrix of 64 <a href="/wiki/Selenium_cell" class="mw-redirect" title="Selenium cell">selenium cells</a>, individually wired to a mechanical <a href="/wiki/Commutator_(electric)" title="Commutator (electric)">commutator</a>, served as an electronic <a href="/wiki/Retina" title="Retina">retina</a>. In the receiver, a type of <a href="/wiki/Kerr_effect" title="Kerr effect">Kerr cell</a> modulated the light and a series of variously angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. A separate circuit regulated synchronization. The 8 x 8 <a href="/wiki/Pixel" title="Pixel">pixel</a> resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> An updated image was transmitted "several times" each second.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>In 1911, <a href="/wiki/Boris_Rosing" title="Boris Rosing">Boris Rosing</a> and his student <a href="/wiki/Vladimir_Zworykin" class="mw-redirect" title="Vladimir Zworykin">Vladimir Zworykin</a> created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "<a href="/wiki/Karl_Ferdinand_Braun" title="Karl Ferdinand Braun">Braun</a> tube" (<a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">cathode-ray tube</a> or "CRT") in the receiver. Moving images were not possible because, in the scanner, "the sensitivity was not enough and the selenium cell was very laggy".<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Television_demonstrations">Television demonstrations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=3" title="Edit section: Television demonstrations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Nipkow_disk.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/08/Nipkow_disk.svg/200px-Nipkow_disk.svg.png" decoding="async" width="200" height="200" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/08/Nipkow_disk.svg/300px-Nipkow_disk.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/08/Nipkow_disk.svg/400px-Nipkow_disk.svg.png 2x" data-file-width="260" data-file-height="260" /></a><figcaption>The <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a>. This schematic shows the circular paths traced by the holes, that may also be square for greater precision. The area of the disk outlined in black shows the region scanned.</figcaption></figure> <p>As a 23-year-old German university student, <a href="/wiki/Paul_Nipkow" class="mw-redirect" title="Paul Nipkow">Paul Julius Gottlieb Nipkow</a> proposed and patented the <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a> in 1884.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image. Although he never built a working model of the system, Nipkow's spinning-disk "<a href="/wiki/Rasterisation" title="Rasterisation">image rasterizer</a>" was the key mechanism used in most mechanical scan systems, in both the transmitter and receiver.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Constantin_Perskyi" title="Constantin Perskyi">Constantin Perskyi</a> had coined the word <i>television</i> in a paper read to the International Electricity Congress at the <a href="/wiki/Exposition_Universelle_(1900)" title="Exposition Universelle (1900)">International World Fair</a> in <a href="/wiki/Paris" title="Paris">Paris</a> on August 24, 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> However, it was the 1907 invention of the first <a href="/wiki/Amplifier" title="Amplifier">amplifying</a> <a href="/wiki/Vacuum_tube" title="Vacuum tube">vacuum tube</a>, the <a href="/wiki/Triode" title="Triode">triode</a>, by <a href="/wiki/Lee_de_Forest" title="Lee de Forest">Lee de Forest</a>, that made the design practical.<sup id="cite_ref-Sending_Photographs_by_Telegraph_17-0" class="reference"><a href="#cite_note-Sending_Photographs_by_Telegraph-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:378px;max-width:378px"><div class="trow"><div class="tsingle" style="width:222px;max-width:222px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:John_Logie_Baird_and_Stooky_Bill.png" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/John_Logie_Baird_and_Stooky_Bill.png/220px-John_Logie_Baird_and_Stooky_Bill.png" decoding="async" width="220" height="167" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/John_Logie_Baird_and_Stooky_Bill.png/330px-John_Logie_Baird_and_Stooky_Bill.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b2/John_Logie_Baird_and_Stooky_Bill.png/440px-John_Logie_Baird_and_Stooky_Bill.png 2x" data-file-width="1071" data-file-height="811" /></a></span></div><div class="thumbcaption">Baird in 1925 with his transmitter equipment and dummies "James" and "Stooky Bill" <i>(right)</i>.</div></div><div class="tsingle" style="width:152px;max-width:152px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:John_Logie_Baird_and_television_receiver.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/John_Logie_Baird_and_television_receiver.jpg/150px-John_Logie_Baird_and_television_receiver.jpg" decoding="async" width="150" height="167" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/John_Logie_Baird_and_television_receiver.jpg/225px-John_Logie_Baird_and_television_receiver.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/John_Logie_Baird_and_television_receiver.jpg/300px-John_Logie_Baird_and_television_receiver.jpg 2x" data-file-width="683" data-file-height="762" /></a></span></div><div class="thumbcaption">Baird and his television receiver</div></div></div></div></div> <p>Scottish inventor <a href="/wiki/John_Logie_Baird" title="John Logie Baird">John Logie Baird</a> in 1925 built some of the first prototype video systems, which employed the <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a>. On March 25, 1925, Baird gave the first public demonstration of televised <a href="/wiki/Silhouette" title="Silhouette">silhouette</a> images in motion, at <a href="/wiki/Selfridges" title="Selfridges">Selfridge's</a> Department Store in London.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> Since human faces had inadequate contrast to show up on his primitive system, he televised a ventriloquist's dummy named "Stooky Bill" talking and moving, whose painted face had higher contrast. By January 26, 1926, he demonstrated the transmission of image of a face in motion by radio. This is widely regarded as being the world's first public television demonstration. Baird's system used the <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a> for both scanning the image and displaying it. A brightly illuminated subject was placed in front of a spinning Nipkow disk set with lenses which swept images across a static photocell. The thallium sulphide (Thalofide) cell, developed by <a href="/wiki/Theodore_Case" title="Theodore Case">Theodore Case</a> in the USA, detected the light reflected from the subject and converted it into a proportional electrical signal. This was transmitted by AM radio waves to a receiver unit, where the video signal was applied to a neon light behind a second Nipkow disk rotating synchronized with the first. The brightness of the neon lamp was varied in proportion to the brightness of each spot on the image. As each hole in the disk passed by, one <a href="/wiki/Scan_line" title="Scan line">scan line</a> of the image was reproduced. Baird's disk had 30 holes, producing an image with only 30 scan lines, just enough to recognize a human face. In 1927, Baird transmitted a signal over 438 miles (705 km) of telephone line between London and <a href="/wiki/Glasgow" title="Glasgow">Glasgow</a>. In 1928, Baird's company (Baird Television Development Company/Cinema Television) broadcast the first transatlantic television signal, between London and New York, and the first shore-to-ship transmission. In 1929, he became involved in the first experimental mechanical television service in Germany. In November of the same year, Baird and <a href="/wiki/Bernard_Natan" title="Bernard Natan">Bernard Natan</a> of <a href="/wiki/Path%C3%A9" title="Pathé">Pathé</a> established France's first television company, Télévision-<a href="/wiki/John_Logie_Baird" title="John Logie Baird">Baird</a>-Natan. In 1931, he made the first outdoor remote broadcast, of <a href="/wiki/Epsom_Derby" title="Epsom Derby">The Derby</a>.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> In 1932, he demonstrated <a href="/wiki/Very_high_frequency" title="Very high frequency">ultra-short wave</a> television. Baird's mechanical system reached a peak of 240-lines of resolution on <a href="/wiki/BBC" title="BBC">BBC</a> television broadcasts in 1936 though the mechanical system did not scan the televised scene directly. Instead a <a href="/wiki/17.5_mm_film" title="17.5 mm film">17.5 mm film</a> was shot, rapidly developed and then scanned while the film was still wet. </p><p>An American inventor, <a href="/wiki/Charles_Francis_Jenkins" title="Charles Francis Jenkins">Charles Francis Jenkins</a> also pioneered the television. He published an article on "Motion Pictures by Wireless" in 1913, but it was not until December 1923 that he transmitted moving silhouette images for witnesses, and it was on June 13, 1925, that he publicly demonstrated synchronized transmission of silhouette pictures. In 1925 Jenkins used <a href="/wiki/Nipkow_disk" title="Nipkow disk">Nipkow disk</a> and transmitted the silhouette image of a toy windmill in motion, over a distance of five miles (8 km) from a naval radio station in Maryland to his laboratory in Washington, D.C., using a lensed disk scanner with a 48-line resolution.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-glinsky_21-0" class="reference"><a href="#cite_note-glinsky-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> He was granted the U.S. patent No. 1,544,156 (Transmitting Pictures over Wireless) on June 30, 1925 (filed March 13, 1922). </p><p>On December 25, 1925, <a href="/wiki/Kenjiro_Takayanagi" title="Kenjiro Takayanagi">Kenjiro Takayanagi</a> demonstrated a television system with a 40-line resolution that employed a Nipkow disk scanner and <a href="/wiki/CRT_display" class="mw-redirect" title="CRT display">CRT display</a> at Hamamatsu Industrial High School in Japan. This prototype is still on display at the Takayanagi Memorial Museum in <a href="/wiki/Shizuoka_University" title="Shizuoka University">Shizuoka University</a>, Hamamatsu Campus.<sup id="cite_ref-nhk.or.jp_22-0" class="reference"><a href="#cite_note-nhk.or.jp-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> By 1927, he improved the resolution to 100 lines, which was unrivaled until 1931.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> By 1928, he was the first to transmit human faces in half-tones. His work had an influence on the later work of <a href="/wiki/Vladimir_K._Zworykin" title="Vladimir K. Zworykin">Vladimir K. Zworykin</a>.<sup id="cite_ref-abramson_24-0" class="reference"><a href="#cite_note-abramson-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> In Japan he is viewed as the man who completed the first all-electronic television.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> His research in creating a production model was halted by the US after Japan lost <a href="/wiki/World_War_II" title="World War II">World War II</a>.<sup id="cite_ref-nhk.or.jp_22-1" class="reference"><a href="#cite_note-nhk.or.jp-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Jenkins_mechanical_scan_television_camera_1931.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Jenkins_mechanical_scan_television_camera_1931.jpg/220px-Jenkins_mechanical_scan_television_camera_1931.jpg" decoding="async" width="220" height="355" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Jenkins_mechanical_scan_television_camera_1931.jpg/330px-Jenkins_mechanical_scan_television_camera_1931.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Jenkins_mechanical_scan_television_camera_1931.jpg/440px-Jenkins_mechanical_scan_television_camera_1931.jpg 2x" data-file-width="495" data-file-height="798" /></a><figcaption>Jenkins Television Co. rotating disk television camera, 1931</figcaption></figure> <p><a href="/wiki/Herbert_E._Ives" title="Herbert E. Ives">Herbert E. Ives</a> and <a href="/wiki/Frank_Gray_(researcher)" title="Frank Gray (researcher)">Frank Gray</a> of Bell Telephone Laboratories gave a dramatic demonstration of mechanical television on April 7, 1927. The reflected-light television system included both small and large viewing screens. The small receiver had a 2 by 2.5 inches (5 by 6 cm) screen (width by height). The large receiver had a screen 24 by 30 inches (61 by 76 cm) (width by height). Both sets were capable of reproducing reasonably accurate, monochromatic moving images. Along with the pictures, the sets also received synchronized sound. The system transmitted images over two paths: first, a <a href="/wiki/Copper_wire_and_cable" class="mw-redirect" title="Copper wire and cable">copper wire</a> link from Washington to New York City, then a radio link from <a href="/wiki/Whippany,_New_Jersey" title="Whippany, New Jersey">Whippany, New Jersey</a>. Comparing the two transmission methods, viewers noted no difference in quality. Subjects of the telecast included <a href="/wiki/Secretary_of_Commerce" class="mw-redirect" title="Secretary of Commerce">Secretary of Commerce</a> <a href="/wiki/Herbert_Hoover" title="Herbert Hoover">Herbert Hoover</a>. A <a href="/wiki/Flying-spot_scanner" title="Flying-spot scanner">flying-spot scanner</a> beam illuminated these subjects. The scanner that produced the beam had a 50-aperture disk. The disc revolved at a rate of 18 frames per second, capturing one frame about every 56 <a href="/wiki/Millisecond" title="Millisecond">milliseconds</a>. (Today's systems typically transmit 30 or 60 frames per second, or one frame every 33.3 or 16.7 milliseconds respectively.) Television historian Albert Abramson underscored the significance of the Bell Labs demonstration: "It was in fact the best demonstration of a mechanical television system ever made to this time. It would be several years before any other system could even begin to compare with it in picture quality."<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> </p><p>In 1928, <a href="/wiki/General_Electric" title="General Electric">General Electric</a> launched their own experimental television station <i>W2XB</i>, broadcasting from the GE plant in Schenectady, New York. The station was popularly known as "<a href="/wiki/WGY_(AM)" title="WGY (AM)">WGY</a> Television", named after the GE owned radio station <a href="/wiki/WGY_(AM)" title="WGY (AM)">WGY</a>. The station eventually converted to an all-electronic system in the 1930s and in 1942, received a commercial license as <a href="/wiki/WRGB" title="WRGB">WRGB</a>. The station is still operating today. </p><p>Meanwhile, in the <a href="/wiki/Soviet_Union" title="Soviet Union">Soviet Union</a>, <a href="/wiki/L%C3%A9on_Theremin" class="mw-redirect" title="Léon Theremin">Léon Theremin</a> had been developing a mirror drum-based television, starting with 16 lines resolution in 1925, then 32 lines and eventually 64 using <a href="/wiki/Interlaced_video" title="Interlaced video">interlacing</a> in 1926, and as part of his thesis on May 7, 1926, he electrically transmitted and then projected near-simultaneous moving images on a five-foot (1.5 m) square screen.<sup id="cite_ref-glinsky_21-1" class="reference"><a href="#cite_note-glinsky-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> By 1927 he achieved an image of 100 lines, a resolution that was not surpassed until 1931 by RCA, with 120 lines.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (September 2009)">citation needed</span></a></i>]</sup> </p><p>Because only a limited number of holes could be made in the disks, and disks beyond a certain diameter became impractical, image resolution on mechanical television broadcasts was relatively low, ranging from about 30 lines up to 120 or so. Nevertheless, the image quality of 30-line transmissions steadily improved with technical advances, and by 1933 the UK broadcasts using the Baird system were remarkably clear.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> A few systems ranging into the 200-line region also went on the air. </p><p>180-lines broadcast tests were carried out by the <a href="/wiki/Reichs-Rundfunk-Gesellschaft" title="Reichs-Rundfunk-Gesellschaft">Reichs-Rundfunk-Gesellschaft</a> in 1935, with a 16 kW (21 hp) transmitter in <a href="/wiki/Berlin" title="Berlin">Berlin</a>.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> Transmissions lasted 90 minutes a day, three days a week, with sound/visions frequencies being 6.7 m (22 ft) and 6.985 m (22.92 ft). </p><p>Likewise, a 180-line system that Compagnie des Compteurs (CDC) installed in <a href="/wiki/Paris" title="Paris">Paris</a> was tested in 1935, and a 180-line system by <a href="/wiki/Peck_Television_Corp." title="Peck Television Corp.">Peck Television Corp.</a> started in 1935 at station VE9AK in <a href="/wiki/Montreal" title="Montreal">Montreal</a>, Quebec, Canada.<sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-halign-center" typeof="mw:File/Thumb"><a href="/wiki/File:Early_Television_System_Diagram.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2a/Early_Television_System_Diagram.png/750px-Early_Television_System_Diagram.png" decoding="async" width="750" height="410" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2a/Early_Television_System_Diagram.png/1125px-Early_Television_System_Diagram.png 1.5x, //upload.wikimedia.org/wikipedia/commons/2/2a/Early_Television_System_Diagram.png 2x" data-file-width="1152" data-file-height="630" /></a><figcaption><div class="center" style="width:auto; margin-left:auto; margin-right:auto;">Block diagram of <a href="/wiki/General_Electric" title="General Electric">General Electric</a> mechanical scan television system, Radio News (April 1928)</div></figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Color_television">Color television</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=4" title="Edit section: Color television"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Colour_Televisor.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Colour_Televisor.JPG/220px-Colour_Televisor.JPG" decoding="async" width="220" height="195" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Colour_Televisor.JPG/330px-Colour_Televisor.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Colour_Televisor.JPG/440px-Colour_Televisor.JPG 2x" data-file-width="2258" data-file-height="2005" /></a><figcaption>A color televisor. A test card (the famous <a href="/wiki/Test_card_F" class="mw-redirect" title="Test card F">test card F</a>) can just be seen through the lens on the right.</figcaption></figure> <p>John Baird's 1928 color television experiments had inspired Goldmark's more advanced <a href="/wiki/Field-sequential_color_system" title="Field-sequential color system">field-sequential color system</a>.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> The CBS <a href="/wiki/Color_television" title="Color television">color television</a> system invented by <a href="/wiki/Peter_Carl_Goldmark" title="Peter Carl Goldmark">Peter Goldmark</a> used such technology in 1940.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> In Goldmark's system, stations transmit color saturation values electronically; however, mechanical methods are also used. At the transmitting camera, a mechanical disc filters hues (colors) from reflected studio lighting. At the receiver, a synchronized disc paints the same hues over the CRT. As the viewer watches pictures through the color disc, the pictures appear in full color. </p><p>Later, simultaneous color systems superseded the CBS-Goldmark system, but mechanical color methods continued to find uses. Early color sets were very expensive: over $1,000 in the money of the time. Inexpensive adapters allowed owners of black-and-white <a href="/wiki/NTSC" title="NTSC">NTSC</a> television sets to receive color telecasts. The most prominent of these adapters is Col-R-Tel, a 1955 NTSC to field-sequential converter.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> This system operates at NTSC scanning rates, but uses a disc like the obsolete CBS system had. The disc converts the black-and-white set to a field-sequential set. Meanwhile, Col-R-Tel electronics recover NTSC color signals and sequence them for disc reproduction. The electronics also synchronize the disc to the NTSC system. In Col-R-Tel, the electronics provide the saturation values (chroma). These electronics cause chroma values to superimpose over brightness (luminance) changes of the picture. The disc paints the hues (color) over the picture. </p><p>A few years after Col-R-Tel, the <a href="/wiki/Apollo_program" title="Apollo program">Apollo Moon missions</a> also adopted field-sequential techniques. The lunar color cameras all had color wheels. These <a href="/wiki/Westinghouse_Electric_Corporation_(1886)" class="mw-redirect" title="Westinghouse Electric Corporation (1886)">Westinghouse</a> and later <a href="/wiki/RCA" title="RCA">RCA</a> cameras sent field-sequential color television pictures to Earth. The Earth receiving stations included electronic equipment that converted the raw colour video signals into the NTSC standard.<sup id="cite_ref-Apollo_Sequential_Color_TV_34-0" class="reference"><a href="#cite_note-Apollo_Sequential_Color_TV-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Decline">Decline</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=5" title="Edit section: Decline"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The advancement of <a href="/wiki/Vacuum_tube" title="Vacuum tube">vacuum tube</a> electronic television (including <a href="/wiki/Image_dissector" title="Image dissector">image dissectors</a> and other camera tubes and CRTs for the reproducer) marked the beginning of the end for mechanical systems as the dominant form of television. Mechanical TV usually only produced small images. It was the main type of TV until the 1930s. </p><p>Vacuum tube television, first demonstrated in September 1927 in <a href="/wiki/San_Francisco" title="San Francisco">San Francisco</a> by <a href="/wiki/Philo_Farnsworth" title="Philo Farnsworth">Philo Farnsworth</a>, and then publicly by Farnsworth at the <a href="/wiki/Franklin_Institute" title="Franklin Institute">Franklin Institute</a> in <a href="/wiki/Philadelphia" title="Philadelphia">Philadelphia</a> in 1934, was rapidly overtaking mechanical television. Farnsworth's system was first used for broadcasting in 1936, reaching 400 to more than 600 lines with fast field scan rates, along with competing systems by <a href="/wiki/Philco" title="Philco">Philco</a> and <a href="/wiki/DuMont_Laboratories" title="DuMont Laboratories">DuMont Laboratories</a>. In 1939, <a href="/wiki/Radio_Corporation_of_America" class="mw-redirect" title="Radio Corporation of America">RCA</a> paid Farnsworth $1 million for his patents after ten years of litigation, and RCA began demonstrating all-electronic television at the <a href="/wiki/1939_World%27s_Fair" class="mw-redirect" title="1939 World's Fair">1939 World's Fair</a> in <a href="/wiki/New_York_City" title="New York City">New York City</a>. The last mechanical television broadcasts ended in 1939 at stations run by a handful of public universities in the United States. </p> <div class="mw-heading mw-heading3"><h3 id="'Scophony'_mechanical_display_receiver"><span id=".27Scophony.27_mechanical_display_receiver"></span>'Scophony' mechanical display receiver</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=6" title="Edit section: 'Scophony' mechanical display receiver"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Scophony" title="Scophony">Scophony</a></div> <p>Early <a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">Cathode-Ray Television tube displays</a> were small in size. The 'Scophony' television receiver of 1938, an advanced television receiver that used a mechanical display, was capable of displaying a 405-line picture (compatible with the then <a href="/wiki/405-line_television_system" title="405-line television system">405-line television system</a> used in the United Kingdom) on a display that was 24-inches wide and 20-inches high. A version intended for theater audiences had a 6 feet wide display. It was also capable of being set up for the US <a href="/wiki/441-line_television_system#United_States" title="441-line television system">441-line television system</a>. For 405 lines, it used a high-speed scanner running at 30,375 r.p.m. and a low speed mirror drum running at around 250 r.p.m., in conjunction with a <a href="/wiki/Jeffree_cell" title="Jeffree cell">Jeffree cell</a> to modulate a focused light beam from a <a href="/wiki/Mercury_lamp" class="mw-redirect" title="Mercury lamp">mercury lamp</a>. It used 39 vacuum tubes in its electronic circuits, and consumed around 1,000 Watts. Although producing impressive results and reaching the marketplace, the receiver was very expensive, costing around twice as much as a cathode-ray television. It was not a commercial success, and television transmissions in the UK were suspended for the duration of the Second World War, sealing its fate. No complete receiver survives, although some components do.<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Modern_applications_of_mechanical_scanning">Modern applications of mechanical scanning</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=7" title="Edit section: Modern applications of mechanical scanning"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Since the 1970s, some <a href="/wiki/Amateur_radio" title="Amateur radio">amateur radio</a> enthusiasts have experimented with mechanical systems. The early light source of a <a href="/wiki/Neon_lamp" title="Neon lamp">neon lamp</a> has now been replaced with super-bright <a href="/wiki/Light-emitting_diode" title="Light-emitting diode">LEDs</a>. There is some interest in creating these systems for <a href="/wiki/Narrow-bandwidth_television" title="Narrow-bandwidth television">narrow-bandwidth television</a>, which would allow a small or large moving image to fit into a channel less than 40 kHz wide (modern TV systems usually have a channel about 6 MHz wide, 150 times larger). Also associated with this is <a href="/wiki/Slow-scan_television" title="Slow-scan television">slow-scan TV</a> – although that typically used electronic systems utilising the P7 CRT until the 1980s and <a href="/wiki/Personal_computer" title="Personal computer">PCs</a> thereafter. There are three known mechanical monitor forms:<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (August 2016)">citation needed</span></a></i>]</sup> two fax printer-like monitors made in the 1970s, and in 2013 a small drum monitor with a coating of glow paint where the image is painted on the rotating drum with a <a href="/wiki/Ultraviolet" title="Ultraviolet">UV</a> laser. </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Mechanical_Television_with_LED_Strips.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Mechanical_Television_with_LED_Strips.jpg/281px-Mechanical_Television_with_LED_Strips.jpg" decoding="async" width="281" height="196" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Mechanical_Television_with_LED_Strips.jpg/422px-Mechanical_Television_with_LED_Strips.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Mechanical_Television_with_LED_Strips.jpg/562px-Mechanical_Television_with_LED_Strips.jpg 2x" data-file-width="2122" data-file-height="1480" /></a><figcaption>Television machine with 4 LED strips</figcaption></figure> <p><a href="/wiki/Digital_light_processing" title="Digital light processing">Digital light processing</a> (DLP) projectors use an array of tiny (16 μm<sup>2</sup>) <a href="/wiki/Electrostatics" title="Electrostatics">electrostatically</a>-actuated mirrors selectively reflecting a light source to create an image. Many low-end DLP systems also use a <a href="/wiki/Color_wheel_(optics)" title="Color wheel (optics)">color wheel</a> to provide a sequential color image, a feature that was common on many early color television systems before the <a href="/wiki/Shadow_mask" title="Shadow mask">shadow mask</a> CRT provided a practical method for producing a simultaneous color image. </p><p>Another place where high-quality imagery is produced by opto-mechanics is the <a href="/wiki/Laser_printer" class="mw-redirect" title="Laser printer">laser printer</a>, where a small rotating mirror is used to deflect a modulated laser beam in one axis while the motion of the <a href="/wiki/Photoconductivity" title="Photoconductivity">photoconductor</a> provides the motion in the other axis. A modification of such a system using high power lasers is used in laser video projectors, with resolutions as high as 1024 lines and each line containing over 1,500 points. Such systems produce, arguably, the best quality video images. They are used, for instance, in <a href="/wiki/Planetarium" title="Planetarium">planetariums</a>. </p><p>Mechanical techniques are also used in long wave <a href="/wiki/Infrared" title="Infrared">infrared</a> cameras used in military applications such as night vision for fighter pilots. These cameras use a high sensitivity infrared photo receptor (usually cooled to increase sensitivity), but instead of conventional lenses, these systems use rotating prisms to provide a 525 or 625 line standard video output. The optical parts are made from germanium, because glass is opaque at the wavelengths involved. Similar cameras have also found a role in sporting events where they are able to show (for example) where a ball has struck a bat. </p><p><a href="/wiki/Laser_lighting_display" title="Laser lighting display">Laser lighting display</a> techniques are combined with computer <a href="/wiki/Emulator" title="Emulator">emulation</a> in the LaserMAME project.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> It is a <a href="/wiki/Vector_graphics" title="Vector graphics">vector</a>-based system, unlike the <a href="/wiki/Raster_scan" title="Raster scan">raster</a> displays thus-far described. <a href="/wiki/Laser" title="Laser">Laser</a> light reflected from computer-controlled mirrors traces out images generated by classic arcade software which is executed by a specially modified version of the <a href="/wiki/MAME" title="MAME">MAME</a> emulation <a href="/wiki/Software" title="Software">software</a>. </p> <div style="clear:both;" class=""></div> <div class="mw-heading mw-heading2"><h2 id="Technical_aspects">Technical aspects</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=8" title="Edit section: Technical aspects"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Flying_spot_scanners">Flying spot scanners</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=9" title="Edit section: Flying spot scanners"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Flying-spot_scanner" title="Flying-spot scanner">Flying-spot scanner</a></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Flying_spot_scanner_1931.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/29/Flying_spot_scanner_1931.jpg/200px-Flying_spot_scanner_1931.jpg" decoding="async" width="200" height="263" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/29/Flying_spot_scanner_1931.jpg/300px-Flying_spot_scanner_1931.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/29/Flying_spot_scanner_1931.jpg/400px-Flying_spot_scanner_1931.jpg 2x" data-file-width="608" data-file-height="798" /></a><figcaption>Flying spot scanner in a television studio in 1931. This type was used for "head shots" of performers speaking, singing or playing instruments. A bright spot of light projected from the lens at center scanned the subject's face, and the light reflected at each point was picked up by the 8 <a href="/wiki/Phototube" title="Phototube">phototubes</a> in the dish-shaped mirrors.</figcaption></figure> <p>The most common method for creating the video signal was the "flying spot scanner", developed as a remedy for the low sensitivity that photoelectric cells had at the time. Instead of a television camera that took pictures, a flying spot scanner projected a bright spot of light that scanned rapidly across the subject scene in a <a href="/wiki/Raster_scan" title="Raster scan">raster</a> pattern, in a darkened studio. The light reflected from the subject was picked up by banks of <a href="/wiki/Photoelectric_cell" class="mw-redirect" title="Photoelectric cell">photoelectric cells</a> and amplified to become the video signal. </p><p>In the scanner the narrow light beam was produced by an <a href="/wiki/Arc_lamp" title="Arc lamp">arc lamp</a> shining through the holes in a spinning Nipkow disk. Each sweep of the spot across the scene produced a "scan line" of the picture. A single "frame" of the picture was typically made up of 24, 48, or 60 scan lines. The scene was typically scanned 15 or 20 times per second, producing 15 or 20 video frames per second. The varying brightness of the point where the spot fell reflected varying amounts of light, which was converted to a proportionally varying electronic signal by the photoelectric cells. To achieve adequate sensitivity, instead of a single cell, a number of photoelectric cells were used. Like mechanical television itself, flying spot technology grew out of phototelegraphy (facsimile). This scanning method began in the 19th century. </p><p>The flying spot method has two disadvantages: </p> <ul><li>Actors must perform in near darkness</li> <li>Flying spot cameras tend to work unreliably outdoors in daylight</li></ul> <p>In 1928, Ray Kell from the United States' <a href="/wiki/General_Electric" title="General Electric">General Electric</a> proved that flying spot scanners could work outdoors. The scanning light source must be brighter than other incident illumination. </p><p>Kell was the engineer who ran a 24-line camera that telecast pictures of New York governor <a href="/wiki/Al_Smith" title="Al Smith">Al Smith</a>. Smith was accepting the Democratic nomination for presidency. As Smith stood outside the capital in Albany, Kell managed to send usable pictures to his associate Bedford at station <a href="/wiki/WGY_(AM)" title="WGY (AM)">WGY</a>, which was broadcasting Smith's speech. The rehearsal went well, but then the real event began. The newsreel cameramen switched on their floodlights. </p><p>Unfortunately for Kell, his scanner only had a 1 kW lamp inside it. The floodlights threw much more light on Governor Smith. These floods simply overwhelmed Kell's imaging photocells. In fact, the floods made the unscanned part of the image as bright as the scanned part. Kell's photocells couldn't discriminate reflections off Smith (from the AC scanning beam) from the flat, DC light from the floodlamps. </p><p>The effect is very similar to extreme overexposure in a still camera: The scene disappears, and the camera records a flat, bright light. If used in favorable conditions, however, the picture comes out correctly. Similarly, Kell proved that outdoors in favorable conditions, his scanner worked. </p> <figure class="mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Flying_spot_scanner_television_studio_1931.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Flying_spot_scanner_television_studio_1931.png/315px-Flying_spot_scanner_television_studio_1931.png" decoding="async" width="315" height="225" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Flying_spot_scanner_television_studio_1931.png/473px-Flying_spot_scanner_television_studio_1931.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Flying_spot_scanner_television_studio_1931.png/630px-Flying_spot_scanner_television_studio_1931.png 2x" data-file-width="1104" data-file-height="788" /></a><figcaption>A scene being televised by flying spot scanner in a television studio in 1931. The Nipkow disk in the flying spot scanner <i>(bottom)</i> projects a spot of light that scans the subject in a raster pattern in the darkened studio. Nearby photocell pickup units convert the reflected light to a signal proportional to the brightness of the reflected area, which goes through the control board to the transmitter.</figcaption></figure> <p>The BBC television service used the flying spot method until 1935, and German television used flying spot methods as late as 1938. However, flying spot techniques remained in use in many applications after the demise of mechanical television. The German inventor <a href="/wiki/Manfred_von_Ardenne" title="Manfred von Ardenne">Manfred von Ardenne</a> designed a flying spot scanner with a CRT as the light source, and CRT-based flying spot scanners became a common technique for <a href="/wiki/Telecine#Flying_spot_scanner" title="Telecine">telecine</a>. In the 1950s, <a href="/wiki/DuMont_Television_Network" title="DuMont Television Network">DuMont</a> marketed <a href="/wiki/Vitascan" title="Vitascan">Vitascan</a>, an entire flying-spot color studio system. <a href="/wiki/Laser_scanner" class="mw-redirect" title="Laser scanner">Laser scanners</a> continue to use a flying spot approach. </p> <div class="mw-heading mw-heading3"><h3 id="Larger_videos">Larger videos</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=10" title="Edit section: Larger videos"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A few mechanical TV systems could produce images several feet or meters wide and of comparable quality to the CRT televisions that were to follow. CRT technology at that time was limited to small, low-brightness screens. One such system was developed by <a href="/wiki/Ulises_Armand_Sanabria" title="Ulises Armand Sanabria">Ulises Armand Sanabria</a> in Chicago. By 1934, Sanabria demonstrated a projection system which had a 30-foot (9.1 m) image.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> </p><p>Perhaps the best<sup class="noprint Inline-Template" style="margin-left:0.1em; white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Manual_of_Style/Words_to_watch#Unsupported_attributions" title="Wikipedia:Manual of Style/Words to watch"><span title="The material near this tag may use weasel words or too-vague attribution. (March 2021)">according to whom?</span></a></i>]</sup> mechanical televisions of the 1930s used the <a href="/wiki/Scophony" title="Scophony">Scophony</a> system, which could produce images of more than 400 lines and display them on screens at least 9 by 12 feet (2.7 m × 3.7 m) in size (at least a few models of this type were actually produced). </p><p>The Scophony system used multiple drums rotating at fairly high speed to create the images. One using a <a href="/wiki/441-line_television_system" title="441-line television system">441-line</a> American standard of the day had a small drum rotating at 39,690 <a href="/wiki/Revolutions_per_minute" title="Revolutions per minute">rpm</a> (a second slower drum moved at just a few hundred rpm). </p> <div class="mw-heading mw-heading3"><h3 id="Aspect_ratios">Aspect ratios</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=11" title="Edit section: Aspect ratios"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Some mechanical equipment scanned lines vertically rather than <a href="/wiki/Horizontal_plane" class="mw-redirect" title="Horizontal plane">horizontally</a>, as in modern TVs. An example of this method is the Baird 30-line system. Baird's British system created a picture in the shape of a very narrow, vertical rectangle. </p><p>This shape created a "<a href="/wiki/Page_orientation" title="Page orientation">portrait</a>" image, instead of the "landscape" orientation – these terms coming from the concepts of <a href="/wiki/Portrait" title="Portrait">portrait</a> and <a href="/wiki/Landscape_painting" title="Landscape painting">landscape</a> in <a href="/wiki/Art" title="Art">art</a> – that is common today. The position of a framing mask before the Nipkow disk determines the scan line orientation. Placement of the framing mask at the left or right side of the disk gives vertical scan lines. Placement at the top or bottom of the disk gives horizontal scan lines. </p><p>Baird's earliest television images had very low definition. These images could only show one person clearly. For this reason, a vertical "portrait" image made more sense to Baird than a horizontal "landscape" image. Baird chose a shape three units wide by seven high. This shape is only about half as wide as a traditional portrait and close in proportion to a typical doorway. </p><p>Instead of entertainment television, Baird might have had point-to-point communication in mind. Another television system followed that reasoning. The 1927 system developed by <a href="/wiki/Herbert_E._Ives" title="Herbert E. Ives">Herbert E. Ives</a> at AT&T's <a href="/wiki/Bell_Laboratories" class="mw-redirect" title="Bell Laboratories">Bell Laboratories</a> was a large-screen television system and the most advanced television of its day. The Ives 50-line system also produced a vertical "portrait" picture. Since AT&T intended to use television for telephony, the vertical shape was logical: phone calls are usually conversations between just two people. A <a href="/wiki/Picturephone" class="mw-redirect" title="Picturephone">picturephone</a> system would depict one person on each side of the line. </p><p>Meanwhile, in the US, Germany and elsewhere, other inventors planned to use television for entertainment purposes. These inventors began with square or "landscape" pictures. (For example, the television systems of <a href="/wiki/Ernst_Alexanderson" title="Ernst Alexanderson">Ernst Alexanderson</a>, <a href="/wiki/Frank_Conrad" title="Frank Conrad">Frank Conrad</a>, <a href="/wiki/Charles_Francis_Jenkins" title="Charles Francis Jenkins">Charles Francis Jenkins</a>, William Peck<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> and <a href="/wiki/Ulises_Armand_Sanabria" title="Ulises Armand Sanabria">Ulises Armand Sanabria</a>.<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup>) These inventors realized that television is about relationships between people.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (March 2021)">citation needed</span></a></i>]</sup> From the very beginning, these inventors allowed picture space for two-shots. Soon, images increased to 60 lines or more. The camera could easily photograph several people at once. Then even Baird switched his picture mask to a horizontal image. Baird's "zone television" is an early example of rethinking his extremely narrow screen format. For entertainment and most other purposes, even today, landscape remains the more practical shape. </p> <div class="mw-heading mw-heading2"><h2 id="Recording">Recording</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=12" title="Edit section: Recording"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Phonovision" title="Phonovision">Phonovision</a></div> <p>In the days of commercial mechanical television transmissions, a system of recording images (but not sound) was developed, using a modified gramophone recorder. Marketed as "<a href="/wiki/Phonovision" title="Phonovision">Phonovision</a>", this system, which was never fully perfected, proved to be complicated to use as well as quite expensive, yet managed to preserve a number of early broadcast images that would otherwise have been lost. Scottish computer engineer Donald F. McLean has painstakingly reconstructed the analogue playback technology required to view these recordings, and has given lectures and presentations on his collection of mechanical television recordings made between 1925 and 1933.<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>Among the discs in Dr. McLean's collection are a number of test recordings made by television pioneer <a href="/wiki/John_Logie_Baird" title="John Logie Baird">John Logie Baird</a> himself. One disc, dated "28th March 1928" and marked with the title "Miss Pounsford", shows several minutes of a woman's face in what appears to be very animated conversation. In 1993, the woman was identified by relatives as Mabel Pounsford, and her brief appearance on the disc is one of the earliest known television video recordings of a human.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Bibliography">Bibliography</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=13" title="Edit section: Bibliography"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Beyer, Rick, <i>The Greatest Stories Never Told : 100 tales from history to astonish, bewilder, & stupefy</i>, A&E Television Networks, 2003, <style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-06-001401-6" title="Special:BookSources/0-06-001401-6">0-06-001401-6</a></li> <li>Cavendish, Marshall (Corp), <i>Inventors and Inventions</i>, Marshall Cavendish, 2007, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-7614-7763-2" title="Special:BookSources/0-7614-7763-2">0-7614-7763-2</a></li> <li>Huurdeman, Anton A., <i>The worldwide history of telecommunications</i>, Wiley-IEEE, 2003, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-471-20505-2" title="Special:BookSources/0-471-20505-2">0-471-20505-2</a></li> <li>Sarkar, Tapan K. et al., <i>History of wireless</i>, John Wiley and Sons, 2006, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-471-71814-9" title="Special:BookSources/0-471-71814-9">0-471-71814-9</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=14" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/List_of_experimental_television_stations" title="List of experimental television stations">List of experimental television stations</a></li> <li><a href="/wiki/List_of_years_in_television" title="List of years in television">List of years in television</a></li> <li><a href="/wiki/Television_systems_before_1940" title="Television systems before 1940">Television systems before 1940</a></li> <li><a href="/wiki/Narrow-bandwidth_television" title="Narrow-bandwidth television">Narrow-bandwidth television</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mechanical_television&action=edit&section=15" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">Huurdeman, p. 149 <i>The first telefax machine to be used in practical operation was invented by an Italian priest and professor of physics, Giovanni Caselli (1815–1891).</i></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">Beyer, p. 100 <i>The telegraph was the hot new technology of the moment, and Caselli wondered if it was possible to send pictures over telegraph wires. He went to work in 1855, and over the course of six years perfected what he called the "pantelegraph." It was the world's first practical fax machine.</i></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160115141648/http://www.telephonecollecting.org/caselli.htm">"Giovanni Caselli and the Pantelegraph"</a>. Archived from <a rel="nofollow" class="external text" href="http://www.telephonecollecting.org/caselli.htm">the original</a> on 2016-01-15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Giovanni+Caselli+and+the+Pantelegraph&rft_id=http%3A%2F%2Fwww.telephonecollecting.org%2Fcaselli.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-Withers-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-Withers_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWithers1887" class="citation book cs1"><a href="/wiki/William_Bramwell_Withers" title="William Bramwell Withers">Withers, William Bramwell</a> (1887). <a rel="nofollow" class="external text" href="https://archive.org/details/historyofballara00with"><i>The History of Ballarat, from the First Pastoral Settlement to the Present Time</i></a> (2nd ed.). Ballarat: F.W. Niven And Co. pp. 316–319. <a href="/wiki/OL_(identifier)" class="mw-redirect" title="OL (identifier)">OL</a> <a rel="nofollow" class="external text" href="https://openlibrary.org/works/OL9436501W">9436501W</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+History+of+Ballarat%2C+from+the+First+Pastoral+Settlement+to+the+Present+Time&rft.place=Ballarat&rft.pages=316-319&rft.edition=2nd&rft.pub=F.W.+Niven+And+Co&rft.date=1887&rft_id=https%3A%2F%2Fopenlibrary.org%2Fworks%2FOL9436501W%23id-name%3DOL&rft.aulast=Withers&rft.aufirst=William+Bramwell&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fhistoryofballara00with&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.histv.net/henry-sutton-telephany-1890">1885 Telephane system diagrams</a> – Telegraphic Journal and Electrical Review 7 November 1890</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://chroniclingamerica.loc.gov/lccn/sn83045462/1896-10-17/ed-1/seq-17.pdf">Pictures by Wire, <i>The Evening Star</i>, (Saturday, 16 October, 1896), p.3.</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20181209123736/https://chroniclingamerica.loc.gov/lccn/sn83045462/1896-10-17/ed-1/seq-17.pdf">Archived</a> December 9, 2018, at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://babel.hathitrust.org/cgi/pt?id=mdp.39015031441952;view=1up;seq=489">"Another Electric Distance-Seer"</a>, <i>Literary Digest</i>, September 11, 1909, page 384.</span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://babel.hathitrust.org/cgi/pt?id=uiug.30112064281592;view=1up;seq=223">"Seeing by Wire"</a>, <i>Industrial World</i>, January 31, 1910, pp. viii-x (reprinted from the <i>London Mail</i>).</span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><i>Ibid.</i></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text">"Television on the Way", <i>Kansas City Star</i>, January 30, 1910, p. 20C. (Reprinted in <i>American Broadcasting</i>, edited by Lawrence W. Lichty and Malachi C. Topping, 1976, pp. 45-46.)</span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://babel.hathitrust.org/cgi/pt?id=pst.000020206536;view=1up;seq=162">"Television 'In Sight'"</a>, <i>The Literary Digest</i>, January 2, 1910, pp. 138-139.</span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text">Henry de Varigny, "<a rel="nofollow" class="external text" href="http://histv2.free.fr/rignoux/rignoux1909.htm">La vision à distance</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160303231305/http://histv2.free.fr/rignoux/rignoux1909.htm">Archived</a> 2016-03-03 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>", <i>L'Illustration</i>, Paris, December 11, 1909, p. 451.</span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=gZcwhVyiMqsC&q=zworykin+rosing+selenium">R. W. Burns, <i>Television: An International History of the Formative Years</i></a>, IET, 1998, p. 119. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-85296-914-7" title="Special:BookSources/0-85296-914-7">0-85296-914-7</a>.</span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text">Shiers, George and May (1997), <i>Early Television: A Bibliographic Guide to 1940</i>. Taylor & Francis, pp. 13, 22. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8240-7782-2" title="Special:BookSources/978-0-8240-7782-2">978-0-8240-7782-2</a>.</span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text">Shiers & Shiers, p. 13, 22.</span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text">"<a rel="nofollow" class="external text" href="https://www.histv.net/perskyi-1900">Télévision au moyen de l'électricité</a>", <i>Congrès Inographs by Telegraph", </i>The New York Times<i>, Sunday Magazine, September 20, 1907, p. 7.</i></span> </li> <li id="cite_note-Sending_Photographs_by_Telegraph-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-Sending_Photographs_by_Telegraph_17-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://query.nytimes.com/gst/abstract.html?res=9A07E4DA1331E733A25757C2A9649C946697D6CF">"Sending Photographs by Telegraph"</a>, <i>The New York Times</i>, Sunday Magazine, September 20, 1907, p. 7.</span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation journal cs1"><a rel="nofollow" class="external text" href="https://doi.org/10.1038%2F115504a0">"Current Topics and Events"</a>. <i>Nature</i>. <b>115</b> (2892): 504–508. 1925. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1925Natur.115..504.">1925Natur.115..504.</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1038%2F115504a0">10.1038/115504a0</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature&rft.atitle=Current+Topics+and+Events&rft.volume=115&rft.issue=2892&rft.pages=504-508&rft.date=1925&rft_id=info%3Adoi%2F10.1038%2F115504a0&rft_id=info%3Abibcode%2F1925Natur.115..504.&rft_id=https%3A%2F%2Fdoi.org%2F10.1038%252F115504a0&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text">J. L. Baird, "<a rel="nofollow" class="external text" href="http://www.bairdtelevision.com/1932.html">Television in 1932</a>", <i>BBC Annual Report</i>, 1933.</span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text">"Radio Shows Far Away Objects in Motion", <i>The New York Times</i>, June 14, 1925, p. 1.</span> </li> <li id="cite_note-glinsky-21"><span class="mw-cite-backlink">^ <a href="#cite_ref-glinsky_21-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-glinsky_21-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGlinsky2000" class="citation book cs1">Glinsky, Albert (2000). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/thereminethermus00glin"><i>Theremin: Ether Music and Espionage</i></a></span>. Urbana, Illinois: University of Illinois Press. pp. <a rel="nofollow" class="external text" href="https://archive.org/details/thereminethermus00glin/page/41">41</a>–45. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-252-02582-2" title="Special:BookSources/0-252-02582-2"><bdi>0-252-02582-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Theremin%3A+Ether+Music+and+Espionage&rft.place=Urbana%2C+Illinois&rft.pages=41-45&rft.pub=University+of+Illinois+Press&rft.date=2000&rft.isbn=0-252-02582-2&rft.aulast=Glinsky&rft.aufirst=Albert&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fthereminethermus00glin&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-nhk.or.jp-22"><span class="mw-cite-backlink">^ <a href="#cite_ref-nhk.or.jp_22-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-nhk.or.jp_22-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160101180643/http://www.nhk.or.jp/strl/aboutstrl/evolution-of-tv-en/p05/"><i>Kenjiro Takayanagi: The Father of Japanese Television</i></a>, NHK (Japan Broadcasting Corporation), 2002, retrieved 2009-05-23.</span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=wQhlFaxDwrsC&pg=PA220"><i>High Above: The untold story of Astra, Europe's leading satellite company</i>, page 220</a>, <a href="/wiki/Springer_Science%2BBusiness_Media" title="Springer Science+Business Media">Springer Science+Business Media</a></span> </li> <li id="cite_note-abramson-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-abramson_24-0">^</a></b></span> <span class="reference-text">Albert Abramson, <i>Zworykin, Pioneer of Television</i>, University of Illinois Press, 1995, p. 231. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-252-02104-5" title="Special:BookSources/0-252-02104-5">0-252-02104-5</a>.</span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><i><a href="/wiki/Popular_Photography" title="Popular Photography">Popular Photography</a></i>, <a rel="nofollow" class="external text" href="https://books.google.com/books?id=DJsbJq2_djkC&pg=PA5">November 1990, page 5</a></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text">Abramson, Albert, <i>The History of Television, 1880 to 1941</i>, McFarland & Co., Inc., 1987, p. 101. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-89950-284-7" title="Special:BookSources/978-0-89950-284-7">978-0-89950-284-7</a>.</span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text">Donald F. McLean, <i>Restoring Baird's Image</i> (London: IEEE, 2000), p. 184.</span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHerbert2004" class="citation book cs1">Herbert, Stephen (2004). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=BlZF20ggFhsC&dq=german+180+lines+tv&pg=PA13"><i>A History of Early Television</i></a>. Taylor & Francis. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/9780415326674" title="Special:BookSources/9780415326674"><bdi>9780415326674</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+History+of+Early+Television&rft.pub=Taylor+%26+Francis&rft.date=2004&rft.isbn=9780415326674&rft.aulast=Herbert&rft.aufirst=Stephen&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DBlZF20ggFhsC%26dq%3Dgerman%2B180%2Blines%2Btv%26pg%3DPA13&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/ve9ak.html">"VE9AK entry at"</a>. Earlytelevision.org<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-03-02</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=VE9AK+entry+at&rft.pub=Earlytelevision.org&rft_id=http%3A%2F%2Fwww.earlytelevision.org%2Fve9ak.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/peck.html">"Peck Television Corporation Console Receiver and Camera"</a>. Early Television Museum<span class="reference-accessdate">. Retrieved <span class="nowrap">18 February</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Peck+Television+Corporation+Console+Receiver+and+Camera&rft.pub=Early+Television+Museum&rft_id=http%3A%2F%2Fwww.earlytelevision.org%2Fpeck.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.thewritingworks.com/nostalgia.html">The Smith, Kline & French Medical Color TV Unit</a>.</span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://novia.net/~ereitan/Color_Sys_CBS.html">CBS Field Sequential Color System</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100105183213/http://novia.net/~ereitan/Color_Sys_CBS.html">Archived</a> 2010-01-05 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>.</span> </li> <li id="cite_note-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-33">^</a></b></span> <span class="reference-text">Hawes Mechanical Television Archive, <a rel="nofollow" class="external text" href="http://www.hawestv.com/mtv_color/colrtel_block.htm">How Col-R-Tel Works</a>.</span> </li> <li id="cite_note-Apollo_Sequential_Color_TV-34"><span class="mw-cite-backlink"><b><a href="#cite_ref-Apollo_Sequential_Color_TV_34-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWood2005" class="citation cs2">Wood, Bill (2005), <a rel="nofollow" class="external text" href="https://www.hq.nasa.gov/alsj/ApolloTV-Acrobat7.pdf">"Apollo Television"</a> <span class="cs1-format">(PDF)</span>, in Jones, Eric M.; Glover, Ken (eds.), <i>Apollo Lunar Surface Journal</i>, Washington, DC: NASA (published 1996–2013), p. 12</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Apollo+Television&rft.btitle=Apollo+Lunar+Surface+Journal&rft.place=Washington%2C+DC&rft.pages=12&rft.pub=NASA&rft.date=2005&rft.aulast=Wood&rft.aufirst=Bill&rft_id=http%3A%2F%2Fwww.hq.nasa.gov%2Falsj%2FApolloTV-Acrobat7.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-35"><span class="mw-cite-backlink"><b><a href="#cite_ref-35">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://blog.scienceandmediamuseum.org.uk/the-last-remaining-scophony-tv-receiver-high-speed-scanner-motor/">"The last remaining Scophony TV receiver high-speed scanner motor?"</a>. <i>National Science and Media Museum blog</i>. 2014-03-21<span class="reference-accessdate">. Retrieved <span class="nowrap">2024-04-21</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=National+Science+and+Media+Museum+blog&rft.atitle=The+last+remaining+Scophony+TV+receiver+high-speed+scanner+motor%3F&rft.date=2014-03-21&rft_id=https%3A%2F%2Fblog.scienceandmediamuseum.org.uk%2Fthe-last-remaining-scophony-tv-receiver-high-speed-scanner-motor%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.earlytelevision.org/yanczer_scophony.html">"The Scophony System"</a>. <i>www.earlytelevision.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-04-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.earlytelevision.org&rft.atitle=The+Scophony+System&rft_id=https%3A%2F%2Fwww.earlytelevision.org%2Fyanczer_scophony.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://nightlase.com.au/lasermame/">"LaserMAME"</a>. 2007-10-15. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20071015191810/http://nightlase.com.au/lasermame/">Archived</a> from the original on 2007-10-15<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-03-12</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=LaserMAME&rft.date=2007-10-15&rft_id=http%3A%2F%2Fnightlase.com.au%2Flasermame%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-38">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/u_a_sanabria.html">"Ulises Armand Sanabria"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Ulises+Armand+Sanabria&rft_id=http%3A%2F%2Fwww.earlytelevision.org%2Fu_a_sanabria.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.terramedia.co.uk/quotations/Quotes_P.htm">Media quotations</a>.</span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/u_a_sanabria.html">"Ulises Armand Sanabria at Early Television website"</a>. Earlytelevision.org<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-03-02</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Ulises+Armand+Sanabria+at+Early+Television+website&rft.pub=Earlytelevision.org&rft_id=http%3A%2F%2Fwww.earlytelevision.org%2Fu_a_sanabria.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AMechanical+television" class="Z3988"></span></span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.tvdawn.com/">The World's Earliest Television Recordings</a>.</span> </li> <li id="cite_note-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-42">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.tvdawn.com/tvimage.htm#RWT115">Phonovision: The Recovered Images</a>.</span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 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class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" decoding="async" width="30" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/45px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/59px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></div> <div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Mechanical-scan_television_systems" class="extiw" title="commons:Category:Mechanical-scan television systems">Mechanical-scan television systems</a></span>.</div></div> </div> <ul><li><a rel="nofollow" class="external text" href="https://www.televisor.co.uk">Televisor</a></li> <li><a rel="nofollow" class="external text" href="https://www.taswegian.com/NBTV/forum/">NBTV Forum - Build Your own Mechanical TV</a></li> <li><a rel="nofollow" class="external text" href="http://www.hawestv.com/">Mechanical Television & Illusion Generators</a></li> <li><a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=n7T1TY6HbLQ">Television with 4 rotating LED – Strips</a></li> <li><a rel="nofollow" class="external text" href="http://www.hawestv.com/mtv_page/mtv_page.htm">Hawes Mechanical Television Archive</a></li> <li><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/">Early Television Foundation and Museum</a></li> <li><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/mechanical_stations.html">List of Mechanical Television Stations in the US and Canada 1928–1939</a></li> <li><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/yanczer_scoph.html">Scophony System</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080517012320/http://www.earlytelevision.org/yanczer_scoph.html">Archived</a> 2008-05-17 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li> <li><a rel="nofollow" class="external text" href="http://www.tvdawn.com/">The World's Earliest Television Recordings – Restored!</a></li> <li><a rel="nofollow" class="external text" href="http://www.hawestv.com/moon_cam/moonctel.htm">Field-sequential, color television on moon missions</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20071015032655/http://www.nightlase.com.au/lasermame/">LaserMAME – Mechanically-scanned, giant versions of vector-based arcade games</a></li> <li><a rel="nofollow" class="external text" href="http://www.earlytelevision.org/w9xaa.html">WCFL is on the air with Television Programs</a> WCFL Radio Magazine Fall-1928</li></ul> <p><br /> </p> <div class="navbox-styles"><style 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abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Video_formats" title="Template:Video formats"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Video_formats" title="Template talk:Video formats"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Video_formats" title="Special:EditPage/Template:Video formats"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Broadcast_video_formats" style="font-size:114%;margin:0 4em"><a href="/wiki/Video" title="Video">Broadcast video formats</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible uncollapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Television" style="font-size:114%;margin:0 4em">Television</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Analog_television" title="Analog television">Analog</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/405-line_television_system" title="405-line television system">405 lines</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CCIR_System_A" title="CCIR System A">System A</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/525_lines" title="525 lines">525 lines</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CCIR_System_M" title="CCIR System M">System M</a> (Color systems: <a href="/wiki/NTSC" title="NTSC">NTSC</a>, <a href="/wiki/NTSC-J" title="NTSC-J">NTSC-J</a>, <a href="/wiki/Clear-Vision" title="Clear-Vision">Clear-Vision</a>, <a href="/wiki/PAL-M" title="PAL-M">PAL-M</a>)</li> <li><a href="/wiki/B-MAC" title="B-MAC">B-MAC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/625_lines" title="625 lines">625 lines</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CCIR_System_B" title="CCIR System B">System B</a>, <a href="/wiki/CCIR_System_C" title="CCIR System C">C</a>, <a href="/wiki/CCIR_System_D" title="CCIR System D">D</a>, <a href="/wiki/CCIR_System_G" title="CCIR System G">G</a>, <a href="/wiki/CCIR_System_H" title="CCIR System H">H</a>, <a href="/wiki/CCIR_System_I" title="CCIR System I">I</a>, <a href="/wiki/CCIR_System_K" title="CCIR System K">K</a>, <a href="/wiki/CCIR_System_L" title="CCIR System L">L</a>, <a href="/wiki/CCIR_System_N" title="CCIR System N">N</a> (Color systems: <a href="/wiki/PAL" title="PAL">PAL</a>, <a href="/wiki/PAL#PALN" title="PAL">PAL-N</a>, <a href="/wiki/PALplus" title="PALplus">PALplus</a>, <a href="/wiki/SECAM" title="SECAM">SECAM</a>)</li> <li><a href="/wiki/Multiplexed_Analogue_Components" title="Multiplexed Analogue Components">MAC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/819_line" title="819 line">819 lines</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CCIR_System_E" title="CCIR System E">System E</a>, <a href="/wiki/CCIR_System_E#System_F" title="CCIR System E">F</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">1125 lines</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Multiple_sub-Nyquist_sampling_encoding" title="Multiple sub-Nyquist sampling encoding">MUSE</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">1250 lines</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/HD-MAC" title="HD-MAC">HD-MAC</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Audio_signal" title="Audio signal">Audio</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Multichannel_television_sound" class="mw-redirect" title="Multichannel television sound">BTSC (MTS)</a></li> <li><a href="/wiki/EIAJ_MTS" title="EIAJ MTS">EIAJ</a></li> <li><a href="/wiki/NICAM" title="NICAM">NICAM</a></li> <li><a href="/wiki/Second_audio_program" title="Second audio program">SAP</a></li> <li><a href="/wiki/Sound-in-Syncs" title="Sound-in-Syncs">Sound-in-Syncs</a></li> <li><a href="/wiki/Zweikanalton" title="Zweikanalton">Zweikanalton (A2/IGR)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Hidden signals</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Closed_captioning" title="Closed captioning">Captioning</a></li> <li><a href="/wiki/CGMS-A" title="CGMS-A">CGMS-A</a></li> <li><a href="/wiki/Electronic_program_guide" title="Electronic program guide">EPG</a></li> <li><a href="/wiki/Ghost-canceling_reference" title="Ghost-canceling reference">GCR</a></li> <li><a href="/wiki/Programme_Delivery_Control" title="Programme Delivery Control">PDC</a></li> <li><a href="/wiki/Teletext" title="Teletext">Teletext</a></li> <li><a href="/wiki/Vertical_blanking_interval" title="Vertical blanking interval">VBI</a></li> <li><a href="/wiki/Video_Encoded_Invisible_Light" title="Video Encoded Invisible Light">VEIL</a></li> <li><a href="/wiki/VIT_signals" title="VIT signals">VIT</a></li> <li><a href="/wiki/Vertical_interval_timecode" title="Vertical interval timecode">VITC</a></li> <li><a href="/wiki/Widescreen_signaling" title="Widescreen signaling">WSS</a></li> <li><a href="/wiki/Extended_Data_Services" title="Extended Data Services">XDS</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Historical</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Television_systems_before_1940" title="Television systems before 1940">Pre-1940</a></li> <li><a class="mw-selflink selflink">Mechanical television</a></li> <li><a href="/wiki/180-line_television_system" title="180-line television system">180-line</a></li> <li><a href="/wiki/343-line_television_system" title="343-line television system">343-line</a></li> <li><a href="/wiki/375-line_television_system" title="375-line television system">375-line</a></li> <li><a href="/wiki/441-line_television_system" title="441-line television system">441-line</a></li> <li><a href="/wiki/455-line_television_system" title="455-line television system">455-line</a></li> <li><a href="/wiki/567-line_television_system" title="567-line television system">567-line</a></li> <li><a href="/wiki/Field-sequential_color_system" title="Field-sequential color system">Field-sequential color system</a></li> <li><a href="/wiki/Soviet_Central_Television#OSKM" title="Soviet Central Television">OSKM</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Digital_television" title="Digital television">Digital</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Interlaced_video" title="Interlaced video">Interlaced</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Standard-definition_television" title="Standard-definition television">SDTV</a> <ul><li><a href="/wiki/480i" title="480i">480i</a></li> <li><a href="/wiki/576i" title="576i">576i</a></li></ul></li> <li><a href="/wiki/High-definition_television" title="High-definition television">HDTV</a> <ul><li><a href="/wiki/1080i" title="1080i">1080i</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Progressive_scan" title="Progressive scan">Progressive</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Low-definition_television" title="Low-definition television">LDTV</a> <ul><li><a href="/wiki/1seg" title="1seg">1seg</a></li> <li><a href="/wiki/Low-definition_television" title="Low-definition television">240p</a></li> <li><a href="/wiki/Low-definition_television" title="Low-definition television">288p</a></li></ul></li> <li><a href="/wiki/Enhanced-definition_television" title="Enhanced-definition television">EDTV</a> <ul><li><a href="/wiki/480p" title="480p">480p</a></li> <li><a href="/wiki/576p" title="576p">576p</a></li></ul></li> <li><a href="/wiki/High-definition_television" title="High-definition television">HDTV</a> <ul><li><a href="/wiki/720p" title="720p">720p</a></li> <li><a href="/wiki/1080p" title="1080p">1080p</a></li></ul></li> <li><a href="/wiki/Ultra-high-definition_television" title="Ultra-high-definition television">UHDTV</a> <ul><li><a href="/wiki/4K_resolution" title="4K resolution">4K</a></li> <li><a href="/wiki/8K_resolution" title="8K resolution">8K</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/H.262/MPEG-2_Part_2" title="H.262/MPEG-2 Part 2">MPEG-2 Video</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ATSC_standards" title="ATSC standards">ATSC</a></li> <li><a href="/wiki/DVB" title="DVB">DVB</a> <ul><li><a href="/wiki/DVB_3D-TV" title="DVB 3D-TV">DVB 3D-TV</a></li></ul></li> <li><a href="/wiki/ISDB" title="ISDB">ISDB</a></li> <li><a href="/wiki/Digital_Terrestrial_Multimedia_Broadcast" title="Digital Terrestrial Multimedia Broadcast">DTMB</a></li> <li><a href="/wiki/ChinaSat_9" title="ChinaSat 9">ABS-S</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Audio_Video_Standard#First_generation" title="Audio Video Standard">AVS</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/China_Multimedia_Mobile_Broadcasting" title="China Multimedia Mobile Broadcasting">CMMB</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Audio_Video_Standard#First_generation" title="Audio Video Standard">AVS+</a><sup id="cite_ref-avs_43-0" class="reference"><a href="#cite_note-avs-43"><span class="cite-bracket">[</span>note 1<span class="cite-bracket">]</span></a></sup></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Digital_Terrestrial_Multimedia_Broadcast" title="Digital Terrestrial Multimedia Broadcast">DTMB</a></li> <li><a href="/wiki/ChinaSat_9" title="ChinaSat 9">ABS-S</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/MPEG-4_Part_2" title="MPEG-4 Part 2">MPEG-4 Visual</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/MobaHo!" title="MobaHo!">MobaHo!</a><sup id="cite_ref-mobaho_44-0" class="reference"><a href="#cite_note-mobaho-44"><span class="cite-bracket">[</span>note 2<span class="cite-bracket">]</span></a></sup></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Advanced_Video_Coding" title="Advanced Video Coding">MPEG-4 AVC</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ATSC_standards#H.264/MPEG-4_AVC" title="ATSC standards">ATSC A/72</a></li> <li><a href="/wiki/China_Multimedia_Mobile_Broadcasting" title="China Multimedia Mobile Broadcasting">CMMB</a></li> <li><a href="/wiki/Digital_multimedia_broadcasting" title="Digital multimedia broadcasting">DMB</a></li> <li><a href="/wiki/Digital_Terrestrial_Multimedia_Broadcast" title="Digital Terrestrial Multimedia Broadcast">DTMB</a></li> <li><a href="/wiki/Digital_Video_Broadcasting" class="mw-redirect" title="Digital Video Broadcasting">DVB</a></li> <li><a href="/wiki/ISDB-T_International" title="ISDB-T International">SBTVD</a></li> <li><a href="/wiki/1seg" title="1seg">1seg</a></li> <li><a href="/wiki/MobaHo!" title="MobaHo!">MobaHo!</a><sup id="cite_ref-mobaho_44-1" class="reference"><a href="#cite_note-mobaho-44"><span class="cite-bracket">[</span>note 2<span class="cite-bracket">]</span></a></sup></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Audio_Video_Standard#Second_generation" title="Audio Video Standard">AVS2</a><sup id="cite_ref-avs_43-1" class="reference"><a href="#cite_note-avs-43"><span class="cite-bracket">[</span>note 1<span class="cite-bracket">]</span></a></sup></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ChinaSat_9" title="ChinaSat 9">ABS-S</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/High_Efficiency_Video_Coding" title="High Efficiency Video Coding">MPEG-H HEVC</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ATSC_3.0" title="ATSC 3.0">ATSC 3.0</a></li> <li><a href="/wiki/Digital_Video_Broadcasting" class="mw-redirect" title="Digital Video Broadcasting">DVB</a></li> <li><a href="/wiki/Digital_multimedia_broadcasting" title="Digital multimedia broadcasting">HD DMB</a></li> <li><a href="/wiki/ISDB#ISDB-S3" title="ISDB">ISDB-S3</a></li> <li><a href="/wiki/Digital_Terrestrial_Multimedia_Broadcast" title="Digital Terrestrial Multimedia Broadcast">DTMB</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em"><a href="/wiki/Surround_sound" title="Surround sound">Audio</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dolby_Digital" title="Dolby Digital">AC-3</a> (<a href="/wiki/Surround_sound" title="Surround sound">5.1</a>)</li> <li><a href="/wiki/Dolby_AC-4" title="Dolby AC-4">AC-4</a></li> <li><a href="/wiki/DTS_(sound_system)" class="mw-redirect" title="DTS (sound system)">DTS</a></li> <li><a href="/wiki/Dynamic_Resolution_Adaptation" title="Dynamic Resolution Adaptation">DRA</a></li> <li><a href="/wiki/MPEG-1_Audio_Layer_II" title="MPEG-1 Audio Layer II">MPEG-1 Audio Layer II</a></li> <li><a href="/wiki/MPEG_Multichannel" title="MPEG Multichannel">MPEG Multichannel</a></li> <li><a href="/wiki/Pulse-code_modulation" title="Pulse-code modulation">PCM</a></li> <li><a href="/wiki/Linear_pulse-code_modulation" class="mw-redirect" title="Linear pulse-code modulation">LPCM</a></li> <li><a href="/wiki/Advanced_Audio_Coding" title="Advanced Audio Coding">AAC</a></li> <li><a href="/wiki/High-Efficiency_Advanced_Audio_Coding" title="High-Efficiency Advanced Audio Coding">HE-AAC</a></li> <li><a href="/wiki/MPEG-H_3D_Audio" title="MPEG-H 3D Audio">MPEG-H 3D Audio</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:5em">Hidden signals</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Active_Format_Description" title="Active Format Description">AFD</a></li> <li><a href="/wiki/Broadcast_flag" title="Broadcast flag">Broadcast flag</a></li> <li><a href="/wiki/Closed_captioning" title="Closed captioning">Captioning</a></li> <li><a href="/wiki/DVB-CPCM" title="DVB-CPCM">CPCM</a></li> <li><a href="/wiki/Electronic_program_guide" title="Electronic program guide">EPG</a></li> <li><a href="/wiki/Teletext" title="Teletext">Teletext</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="text-align: left;"><div><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-avs-43"><span class="mw-cite-backlink">^ <a href="#cite_ref-avs_43-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-avs_43-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">Also used in China's DVB-S/S2 network.</span> </li> <li id="cite_note-mobaho-44"><span class="mw-cite-backlink">^ <a href="#cite_ref-mobaho_44-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-mobaho_44-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">Defunct.</span> </li> </ol></div></div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Technical_issues" style="font-size:114%;margin:0 4em">Technical issues</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/14:9" class="mw-redirect" title="14:9">14:9 compromise</a></li> <li><a href="/wiki/Broadcast-safe" title="Broadcast-safe">Broadcast-safe</a></li> <li><a href="/wiki/Digital_cinema" title="Digital cinema">Digital cinema</a> (<a href="/wiki/Digital_Cinema_Initiative" class="mw-redirect" title="Digital Cinema Initiative">DCI</a>)</li> <li><a href="/wiki/Display_motion_blur" title="Display motion blur">Display motion blur</a></li> <li><a href="/wiki/Moving_image_formats" title="Moving image formats">Moving image formats</a></li> <li><a href="/wiki/MPEG_transport_stream" title="MPEG transport stream">MPEG transport stream</a></li> <li><a href="/wiki/Reverse_Standards_Conversion" title="Reverse Standards Conversion">Reverse Standards Conversion</a></li> <li><a href="/wiki/Television_standards_conversion" title="Television standards conversion">Standards conversion</a></li> <li><a href="/wiki/Television_transmitter" title="Television transmitter">Television transmitter</a></li> <li><a href="/wiki/Test_card" title="Test card">Test card</a></li> <li><a href="/wiki/Video_on_demand" title="Video on demand">Video on demand</a></li> <li><a href="/wiki/Video_processing" title="Video processing">Video processing</a></li> <li><a href="/wiki/Widescreen_signaling" title="Widescreen signaling">Widescreen signaling</a></li> <li>Templates (<a href="/wiki/Template:Analogue_TV_transmitter_topics" title="Template:Analogue TV transmitter topics">Analogue TV Topics</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Telecommunications" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Telecommunications" title="Template:Telecommunications"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Telecommunications" title="Template talk:Telecommunications"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Telecommunications" title="Special:EditPage/Template:Telecommunications"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Telecommunications" style="font-size:114%;margin:0 4em"><a href="/wiki/Telecommunications" title="Telecommunications">Telecommunications</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/History_of_telecommunication" title="History of telecommunication">History</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Beacon#For_defensive_communications" title="Beacon">Beacon</a></li> <li><a href="/wiki/History_of_broadcasting" title="History of broadcasting">Broadcasting</a></li> <li><a href="/wiki/Cable_protection_system" title="Cable protection system">Cable protection system</a></li> <li><a href="/wiki/Cable_television" title="Cable television">Cable TV</a></li> <li><a href="/wiki/Communications_satellite#History" title="Communications satellite">Communications satellite</a></li> <li><a href="/wiki/Computer_network#History" title="Computer network">Computer network</a></li> <li><a href="/wiki/Data_compression" title="Data compression">Data compression</a> <ul><li><a href="/wiki/Audio_coding_format" title="Audio coding format">audio</a></li> <li><a href="/wiki/Discrete_cosine_transform" title="Discrete cosine transform">DCT</a></li> <li><a href="/wiki/Image_compression" title="Image compression">image</a></li> <li><a href="/wiki/Video_coding_format" title="Video coding format">video</a></li></ul></li> <li><a href="/wiki/Digital_media" title="Digital media">Digital media</a> <ul><li><a href="/wiki/Internet_video" title="Internet video">Internet video</a></li> <li><a href="/wiki/Online_video_platform" title="Online video platform">online video platform</a></li> <li><a href="/wiki/Social_media" title="Social media">social media</a></li> <li><a href="/wiki/Streaming_media" title="Streaming media">streaming</a></li></ul></li> <li><a href="/wiki/Drums_in_communication" title="Drums in communication">Drums</a></li> <li><a href="/wiki/Edholm%27s_law" title="Edholm's law">Edholm's law</a></li> <li><a href="/wiki/Electrical_telegraph#History" title="Electrical telegraph">Electrical telegraph</a></li> <li><a href="/wiki/Fax#History" title="Fax">Fax</a></li> <li><a href="/wiki/Heliograph#History" title="Heliograph">Heliographs</a></li> <li><a href="/wiki/Hydraulic_telegraph#Greek_hydraulic_semaphore_system" title="Hydraulic telegraph">Hydraulic telegraph</a></li> <li><a href="/wiki/Information_Age" title="Information Age">Information Age</a></li> <li><a href="/wiki/Information_revolution" class="mw-redirect" title="Information revolution">Information revolution</a></li> <li><a href="/wiki/History_of_the_Internet" title="History of the Internet">Internet</a></li> <li><a href="/wiki/Mass_media#History" title="Mass media">Mass media</a></li> <li><a href="/wiki/History_of_mobile_phones" title="History of mobile phones">Mobile phone</a> <ul><li><a href="/wiki/Smartphone" title="Smartphone">Smartphone</a></li></ul></li> <li><a href="/wiki/Optical_communication" title="Optical communication">Optical telecommunication</a></li> <li><a href="/wiki/Optical_telegraph" title="Optical telegraph">Optical telegraphy</a></li> <li><a href="/wiki/Pager" title="Pager">Pager</a></li> <li><a href="/wiki/Photophone" title="Photophone">Photophone</a></li> <li><a href="/wiki/History_of_prepaid_mobile_phones" title="History of prepaid mobile phones">Prepaid mobile phone</a></li> <li><a href="/wiki/History_of_radio" title="History of radio">Radio</a></li> <li><a href="/wiki/Radiotelephone" title="Radiotelephone">Radiotelephone</a></li> <li><a href="/wiki/Communications_satellite" title="Communications satellite">Satellite communications</a></li> <li><a href="/wiki/Semaphore" title="Semaphore">Semaphore</a> <ul><li><a href="/wiki/Phryctoria" title="Phryctoria">Phryctoria</a></li></ul></li> <li><a href="/wiki/Semiconductor" title="Semiconductor">Semiconductor</a> <ul><li><a href="/wiki/Semiconductor_device" title="Semiconductor device">device</a></li> <li><a href="/wiki/MOSFET" title="MOSFET">MOSFET</a></li> <li><a href="/wiki/History_of_the_transistor" title="History of the transistor">transistor</a></li></ul></li> <li><a href="/wiki/Smoke_signal" title="Smoke signal">Smoke signals</a></li> <li><a href="/wiki/History_of_telecommunication" title="History of telecommunication">Telecommunications history</a></li> <li><a href="/wiki/Telautograph" title="Telautograph">Telautograph</a></li> <li><a href="/wiki/Telegraphy" title="Telegraphy">Telegraphy</a></li> <li><a href="/wiki/Teleprinter" title="Teleprinter">Teleprinter</a> (teletype)</li> <li><a href="/wiki/History_of_the_telephone" title="History of the telephone">Telephone</a></li> <li><i><a href="/wiki/The_Telephone_Cases" title="The Telephone Cases">The Telephone Cases</a></i></li> <li><a href="/wiki/History_of_television" title="History of television">Television</a> <ul><li><a href="/wiki/Digital_television" title="Digital television">digital</a></li> <li><a href="/wiki/Streaming_television" title="Streaming television">streaming</a></li></ul></li> <li><a href="/wiki/Submarine_communications_cable#Early_history:_telegraph_and_coaxial_cables" title="Submarine communications cable">Undersea telegraph line</a></li> <li><a href="/wiki/History_of_videotelephony" title="History of videotelephony">Videotelephony</a></li> <li><a href="/wiki/Whistled_language" title="Whistled language">Whistled language</a></li> <li><a href="/wiki/Wireless_revolution" class="mw-redirect" title="Wireless revolution">Wireless revolution</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Pioneers</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nasir_Ahmed_(engineer)" title="Nasir Ahmed (engineer)">Nasir Ahmed</a></li> <li><a href="/wiki/Edwin_Howard_Armstrong" title="Edwin Howard Armstrong">Edwin Howard Armstrong</a></li> <li><a href="/wiki/Mohamed_M._Atalla" title="Mohamed M. Atalla">Mohamed M. Atalla</a></li> <li><a href="/wiki/John_Logie_Baird" title="John Logie Baird">John Logie Baird</a></li> <li><a href="/wiki/Paul_Baran" title="Paul Baran">Paul Baran</a></li> <li><a href="/wiki/John_Bardeen" title="John Bardeen">John Bardeen</a></li> <li><a href="/wiki/Alexander_Graham_Bell" title="Alexander Graham Bell">Alexander Graham Bell</a></li> <li><a href="/wiki/Emile_Berliner" title="Emile Berliner">Emile Berliner</a></li> <li><a href="/wiki/Tim_Berners-Lee" title="Tim Berners-Lee">Tim Berners-Lee</a></li> <li><a href="/wiki/Francis_Blake_(inventor)" title="Francis Blake (inventor)">Francis Blake</a></li> <li><a href="/wiki/Jagadish_Chandra_Bose" title="Jagadish Chandra Bose">Jagadish Chandra Bose</a></li> <li><a href="/wiki/Charles_Bourseul" title="Charles Bourseul">Charles Bourseul</a></li> <li><a href="/wiki/Walter_Houser_Brattain" title="Walter Houser Brattain">Walter Houser Brattain</a></li> <li><a href="/wiki/Vint_Cerf" title="Vint Cerf">Vint Cerf</a></li> <li><a href="/wiki/Claude_Chappe" title="Claude Chappe">Claude Chappe</a></li> <li><a href="/wiki/Yogen_Dalal" class="mw-redirect" title="Yogen Dalal">Yogen Dalal</a></li> <li><a href="/wiki/Daniel_Davis_Jr." title="Daniel Davis Jr.">Daniel Davis Jr.</a></li> <li><a href="/wiki/Donald_Davies" title="Donald Davies">Donald Davies</a></li> <li><a href="/wiki/Amos_Dolbear" title="Amos Dolbear">Amos Dolbear</a></li> <li><a href="/wiki/Thomas_Edison" title="Thomas Edison">Thomas Edison</a></li> <li><a href="/wiki/Lee_de_Forest" title="Lee de Forest">Lee de Forest</a></li> <li><a href="/wiki/Philo_Farnsworth" title="Philo Farnsworth">Philo Farnsworth</a></li> <li><a href="/wiki/Reginald_Fessenden" title="Reginald Fessenden">Reginald Fessenden</a></li> <li><a href="/wiki/Elisha_Gray" title="Elisha Gray">Elisha Gray</a></li> <li><a href="/wiki/Oliver_Heaviside" title="Oliver Heaviside">Oliver Heaviside</a></li> <li><a href="/wiki/Robert_Hooke" title="Robert Hooke">Robert Hooke</a></li> <li><a href="/wiki/Erna_Schneider_Hoover" title="Erna Schneider Hoover">Erna Schneider Hoover</a></li> <li><a href="/wiki/Harold_Hopkins_(physicist)" title="Harold Hopkins (physicist)">Harold Hopkins</a></li> <li><a href="/wiki/Gardiner_Greene_Hubbard" title="Gardiner Greene Hubbard">Gardiner Greene Hubbard</a></li> <li><a href="/wiki/List_of_Internet_pioneers" title="List of Internet pioneers">Internet pioneers</a></li> <li><a href="/wiki/Bob_Kahn" class="mw-redirect" title="Bob Kahn">Bob Kahn</a></li> <li><a href="/wiki/Dawon_Kahng" title="Dawon Kahng">Dawon Kahng</a></li> <li><a href="/wiki/Charles_K._Kao" title="Charles K. Kao">Charles K. Kao</a></li> <li><a href="/wiki/Narinder_Singh_Kapany" title="Narinder Singh Kapany">Narinder Singh Kapany</a></li> <li><a href="/wiki/Hedy_Lamarr" title="Hedy Lamarr">Hedy Lamarr</a></li> <li><a href="/wiki/Roberto_Landell_de_Moura" title="Roberto Landell de Moura">Roberto Landell de Moura</a></li> <li><a href="/wiki/Innocenzo_Manzetti" title="Innocenzo Manzetti">Innocenzo Manzetti</a></li> <li><a href="/wiki/Guglielmo_Marconi" title="Guglielmo Marconi">Guglielmo Marconi</a></li> <li><a href="/wiki/Robert_Metcalfe" title="Robert Metcalfe">Robert Metcalfe</a></li> <li><a href="/wiki/Antonio_Meucci" title="Antonio Meucci">Antonio Meucci</a></li> <li><a href="/wiki/Samuel_Morse" title="Samuel Morse">Samuel Morse</a></li> <li><a href="/wiki/Jun-ichi_Nishizawa" title="Jun-ichi Nishizawa">Jun-ichi Nishizawa</a></li> <li><a href="/wiki/Charles_Grafton_Page" title="Charles Grafton Page">Charles Grafton Page</a></li> <li><a href="/wiki/Radia_Perlman" title="Radia Perlman">Radia Perlman</a></li> <li><a href="/wiki/Alexander_Stepanovich_Popov" class="mw-redirect" title="Alexander Stepanovich Popov">Alexander Stepanovich Popov</a></li> <li><a href="/wiki/Tivadar_Pusk%C3%A1s" title="Tivadar Puskás">Tivadar Puskás</a></li> <li><a href="/wiki/Johann_Philipp_Reis" title="Johann Philipp Reis">Johann Philipp Reis</a></li> <li><a href="/wiki/Claude_Shannon" title="Claude Shannon">Claude Shannon</a></li> <li><a href="/wiki/Almon_Brown_Strowger" title="Almon Brown Strowger">Almon Brown Strowger</a></li> <li><a href="/wiki/Henry_Sutton_(inventor)" title="Henry Sutton (inventor)">Henry Sutton</a></li> <li><a href="/wiki/Charles_Sumner_Tainter" title="Charles Sumner Tainter">Charles Sumner Tainter</a></li> <li><a href="/wiki/Nikola_Tesla" title="Nikola Tesla">Nikola Tesla</a></li> <li><a href="/wiki/Camille_Tissot" title="Camille Tissot">Camille Tissot</a></li> <li><a href="/wiki/Alfred_Vail" title="Alfred Vail">Alfred Vail</a></li> <li><a href="/wiki/Thomas_A._Watson" title="Thomas A. Watson">Thomas A. Watson</a></li> <li><a href="/wiki/Charles_Wheatstone" title="Charles Wheatstone">Charles Wheatstone</a></li> <li><a href="/wiki/Vladimir_K._Zworykin" title="Vladimir K. Zworykin">Vladimir K. Zworykin</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Transmission_medium" title="Transmission medium">Transmission<br />media</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Coaxial_cable" title="Coaxial cable">Coaxial cable</a></li> <li><a href="/wiki/Fiber-optic_communication" title="Fiber-optic communication">Fiber-optic communication</a> <ul><li><a href="/wiki/Optical_fiber" title="Optical fiber">optical fiber</a></li></ul></li> <li><a href="/wiki/Free-space_optical_communication" title="Free-space optical communication">Free-space optical communication</a></li> <li><a href="/wiki/Molecular_communication" title="Molecular communication">Molecular communication</a></li> <li><a href="/wiki/Radio_wave" title="Radio wave">Radio waves</a> <ul><li><a href="/wiki/Wireless" title="Wireless">wireless</a></li></ul></li> <li><a href="/wiki/Transmission_line" title="Transmission line">Transmission line</a> <ul><li><a href="/wiki/Telecommunication_circuit" title="Telecommunication circuit">telecommunication circuit</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Network_topology" title="Network topology">Network topology</a><br />and switching</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bandwidth_(computing)" title="Bandwidth (computing)">Bandwidth</a></li> <li><a href="/wiki/Telecommunications_link" title="Telecommunications link">Links</a></li> <li><a href="/wiki/Node_(networking)" title="Node (networking)">Nodes</a> <ul><li><a href="/wiki/Terminal_(telecommunication)" title="Terminal (telecommunication)">terminal</a></li></ul></li> <li><a href="/wiki/Network_switch" title="Network switch">Network switching</a> <ul><li><a href="/wiki/Circuit_switching" title="Circuit switching">circuit</a></li> <li><a href="/wiki/Packet_switching" title="Packet switching">packet</a></li></ul></li> <li><a href="/wiki/Telephone_exchange" title="Telephone exchange">Telephone exchange</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Multiplexing" title="Multiplexing">Multiplexing</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Space-division_multiple_access" title="Space-division multiple access">Space-division</a></li> <li><a href="/wiki/Frequency-division_multiplexing" title="Frequency-division multiplexing">Frequency-division</a></li> <li><a href="/wiki/Time-division_multiplexing" title="Time-division multiplexing">Time-division</a></li> <li><a href="/wiki/Polarization-division_multiplexing" title="Polarization-division multiplexing">Polarization-division</a></li> <li><a href="/wiki/Orbital_angular_momentum_multiplexing" title="Orbital angular momentum multiplexing">Orbital angular-momentum</a></li> <li><a href="/wiki/Code-division_multiple_access" title="Code-division multiple access">Code-division</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Communication_protocol" title="Communication protocol">Communication protocol</a></li> <li><a href="/wiki/Computer_network" title="Computer network">Computer network</a></li> <li><a href="/wiki/Data_communication" title="Data communication">Data transmission</a></li> <li><a href="/wiki/Store_and_forward" title="Store and forward">Store and forward</a></li> <li><a href="/wiki/Telecommunications_equipment" title="Telecommunications equipment">Telecommunications equipment</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Telecommunications_network" title="Telecommunications network">Types of network</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cellular_network" title="Cellular network">Cellular network</a></li> <li><a href="/wiki/Ethernet" title="Ethernet">Ethernet</a></li> <li><a href="/wiki/Integrated_Services_Digital_Network" class="mw-redirect" title="Integrated Services Digital Network">ISDN</a></li> <li><a href="/wiki/Local_area_network" title="Local area network">LAN</a></li> <li><a href="/wiki/Mobile_telephony" title="Mobile telephony">Mobile</a></li> <li><a href="/wiki/Next-generation_network" title="Next-generation network">NGN</a></li> <li><a href="/wiki/Public_switched_telephone_network" title="Public switched telephone network">Public Switched Telephone</a></li> <li><a href="/wiki/Radio_network" title="Radio network">Radio</a></li> <li><a href="/wiki/Television_broadcasting" class="mw-redirect" title="Television broadcasting">Television</a></li> <li><a href="/wiki/Telex" title="Telex">Telex</a></li> <li><a href="/wiki/UUCP" title="UUCP">UUCP</a></li> <li><a href="/wiki/Wide_area_network" title="Wide area network">WAN</a></li> <li><a href="/wiki/Wireless_network" title="Wireless network">Wireless network</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Telecommunications_network" title="Telecommunications network">Notable networks</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ARPANET" title="ARPANET">ARPANET</a></li> <li><a href="/wiki/BITNET" title="BITNET">BITNET</a></li> <li><a href="/wiki/CYCLADES" title="CYCLADES">CYCLADES</a></li> <li><a href="/wiki/FidoNet" title="FidoNet">FidoNet</a></li> <li><a href="/wiki/Internet" title="Internet">Internet</a></li> <li><a href="/wiki/Internet2" title="Internet2">Internet2</a></li> <li><a href="/wiki/JANET" title="JANET">JANET</a></li> <li><a href="/wiki/NPL_network" title="NPL network">NPL network</a></li> <li><a href="/wiki/Toasternet" title="Toasternet">Toasternet</a></li> <li><a href="/wiki/Usenet" title="Usenet">Usenet</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Locations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Category:Telecommunications_in_Africa" title="Category:Telecommunications in Africa">Africa</a></li> <li>Americas <ul><li><a href="/wiki/Category:Telecommunications_in_North_America" title="Category:Telecommunications in North America">North</a></li> <li><a href="/wiki/Category:Telecommunications_in_South_America" title="Category:Telecommunications in South America">South</a></li></ul></li> <li><a href="/wiki/Category:Communications_in_Antarctica" title="Category:Communications in Antarctica">Antarctica</a></li> <li><a href="/wiki/Category:Telecommunications_in_Asia" title="Category:Telecommunications in Asia">Asia</a></li> <li><a href="/wiki/Category:Telecommunications_in_Europe" title="Category:Telecommunications in Europe">Europe</a></li> <li><a href="/wiki/Category:Telecommunications_in_Oceania" title="Category:Telecommunications in Oceania">Oceania</a></li> <li>(<a href="/wiki/List_of_telecommunications_regulatory_bodies" title="List of telecommunications regulatory bodies">Global telecommunications regulation bodies</a>)</li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="nowrap"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/Telecom-icon.svg/16px-Telecom-icon.svg.png" decoding="async" width="16" height="16" class="mw-file-element" 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