Mechanical television

192: 473: 956: 357: 787: 27: 341: 1092:.) These inventors realized that television is about relationships between people. 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. 886: 584: 1110:", 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. 4186: 915:

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.

746:. 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. 4196: 603: 511:. (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." 4175: 276: 4206: 38:. 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. 636:

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.

405:. 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 216:

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

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television sets to receive color telecasts. The most prominent of these adapters is Col-R-Tel, a 1955 NTSC to field-sequential converter. 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.

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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

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used such technology in 1940. 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

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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.

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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. He was granted the U.S. patent No. 1,544,156 (Transmitting

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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". The limited number of elements meant his device was only capable of representing simple geometric shapes, and the cost

1052: – 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. 914:

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

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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

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Department Store in London. 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

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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

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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

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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

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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

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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

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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

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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

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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.

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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

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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

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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

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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. By 1927 he achieved an image of 100 lines, a resolution that was not surpassed until 1931 by RCA, with 120 lines.

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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

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A few mechanical TV systems could produce images several feet or meters wide and of comparable quality to the cathode ray tube (CRT) televisions that were to follow. CRT technology at that time was limited to small, low-brightness screens. One such system was developed by

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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

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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

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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

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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

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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

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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

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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.

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thereafter. There are three known mechanical monitor forms: 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

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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

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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

461:, Hamamatsu Campus. By 1927, he improved the resolution to 100 lines, which was unrivaled until 1931. By 1928, he was the first to transmit human faces in half-tones. His work had an influence on the later work of 770:, 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 691:

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

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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).

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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.

211:, 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 734:

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

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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

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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

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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. A matrix of 64

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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.

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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.

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in 1884. 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 "

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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

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steadily improved with technical advances, and by 1933 the UK broadcasts using the Baird system were remarkably clear. A few systems ranging into the 200-line region also went on the air.

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resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet. An updated image was transmitted "several times" each second.

940:. 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 30:

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

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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

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on August 24, 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others. However, it was the 1907 invention of the first

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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.

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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

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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 "

283:. 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. 465:. In Japan he is viewed as the man who completed the first all-electronic television. His research in creating a production model was halted by the US after Japan lost 1033:, 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. 4230: 858:

light reflected from computer-controlled mirrors traces out images generated by classic arcade software which is executed by a specially modified version of the

3450: 1313: 565:. 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). 267:

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".

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demonstrated a working laboratory version in 1851. The first practical facsimile system, working on telegraph lines, was developed and put into service by

944:, which was broadcasting Smith's speech. The rehearsal went well, but then the real event began. The newsreel cameramen switched on their floodlights. 738:. 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 1225:

The first telefax machine to be used in practical operation was invented by an Italian priest and professor of physics, Giovanni Caselli (1815–1891).

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cell. Sutton's design was published internationally in 1890. An account of its use to transmit and preserve a still image was published in the

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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

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paid Farnsworth $ 1 million for his patents after ten years of litigation, and RCA began demonstrating all-electronic television at the

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had been developing a mirror drum-based television, starting with 16 lines resolution in 1925, then 32 lines and eventually 64 using

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created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "

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proved that flying spot scanners could work outdoors. The scanning light source must be brighter than other incident illumination.

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designed a flying spot scanner with a CRT as the light source, and CRT-based flying spot scanners became a common technique for

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display at Hamamatsu Industrial High School in Japan. This prototype is still on display at the Takayanagi Memorial Museum in

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motion by radio. This is widely regarded as being the world's first public television demonstration. Baird's system used the

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A scene being televised by flying spot scanner in a television studio in 1931. The Nipkow disk in the flying spot scanner

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scanning device, such as a rotating disk with holes in it or a rotating mirror drum, to scan the scene and generate the

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couldn't discriminate reflections off Smith (from the AC scanning beam) from the flat, DC light from the floodlamps.

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same hues over the CRT. As the viewer watches pictures through the color disc, the pictures appear in full color.

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to provide a sequential color image, a feature that was common on many early color television systems before the

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television broadcasts in 1936 though the mechanical system did not scan the televised scene directly. Instead a

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The Scophony system used multiple drums rotating at fairly high speed to create the images. One using a

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in Chicago. By 1934, Sanabria demonstrated a projection system which had a 30-foot (9.1 m) image.

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Among the discs in Dr. McLean's collection are a number of test recordings made by television pioneer

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Ernst Ruhmer demonstrating his experimental television system, which was capable of transmitting 5×5

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signal, and a similar mechanical device at the receiver to display the picture. This contrasts with

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demonstrated a television system with a 40-line resolution that employed a Nipkow disk scanner and

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The Greatest Stories Never Told : 100 tales from history to astonish, bewilder, & stupefy

4240: 4018: 4003: 3847: 3798: 3721: 3621: 3299: 3185: 3180: 1085: 774:– although that typically used electronic systems utilising the P7 CRT until the 1980s and 484: 472: 437: 157: 54: 2764: 3940: 3726: 3541: 3486: 3481: 3294: 3259: 3086: 2440: 2097: 1089: 1018: 999: 839: 522:, broadcasting from the GE plant in Schenectady, New York. The station was popularly known as " 74: 1644: 903:

pattern, in a darkened studio. The light reflected from the subject was picked up by banks of

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also adopted field-sequential techniques. The lunar color cameras all had color wheels. These

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images of simple shapes over telephone lines, using a 25-element selenium cell receiver (1909)

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Kell was the engineer who ran a 24-line camera that telecast pictures of New York governor

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The first mechanical raster scanning techniques were developed in the 19th century for

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John Baird's 1928 color television experiments had inspired Goldmark's more advanced

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enthusiasts have experimented with mechanical systems. The early light source of a

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television. Baird's mechanical system reached a peak of 240-lines of resolution on

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Baird in 1925 with his transmitter equipment and dummies "James" and "Stooky Bill"

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The History of Ballarat, from the First Pastoral Settlement to the Present Time

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Another place where high-quality imagery is produced by opto-mechanics is the

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LaserMAME – Mechanically-scanned, giant versions of vector-based arcade games

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wide as a traditional portrait and close in proportion to a typical doorway.

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Likewise, a 180-line system that Compagnie des Compteurs (CDC) installed in

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in 1925 built some of the first prototype video systems, which employed the

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was shot, rapidly developed and then scanned while the film was still wet.

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High Above: The untold story of Astra, Europe's leading satellite company

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provided a practical method for producing a simultaneous color image.

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List of Mechanical Television Stations in the US and Canada 1928–1939

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American standard of the day had a small drum rotating at 39,690

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Pictures over Wireless) on June 30, 1925 (filed March 13, 1922).

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in a paper read to the International Electricity Congress at the

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Flying spot cameras tend to work unreliably outdoors in daylight

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Vacuum tube television, first demonstrated in September 1927 in

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Some mechanical equipment scanned lines vertically rather than

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Perhaps the best mechanical televisions of the 1930s used the

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link from Washington to New York City, then a radio link from

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for transmission of images via telegraph wires, based on the

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Television that relies on a scanning device to display images

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Jenkins Television Co. rotating disk television camera, 1931

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which was used as a pickup in most mechanical scan systems.

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Television: An International History of the Formative Years

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mechanical scan television system, Radio News (April 1928)

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established France's first television company, Télévision-

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system would depict one person on each side of the line.

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In the scanner the narrow light beam was produced by an

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are now used to create and display television pictures.

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earliest known television video recordings of a human.

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in 1935, with a 16 kW (21 hp) transmitter in

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transmission of images was made by a German physicist,

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The World's Earliest Television Recordings – Restored!

19:"Televisor" redirects here. Not to be confused with a 1632:

Kenjiro Takayanagi: The Father of Japanese Television

1972:"Ulises Armand Sanabria at Early Television website" 526:

Television", named after the GE owned radio station

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Field-sequential, color television on moon missions

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The Smith, Kline & French Medical Color TV Unit

1351:, January 31, 1910, pp. viii-x (reprinted from the 518:launched their own experimental television station 96:A mechanical television receiver was also called a 1596: 557:180-lines broadcast tests were carried out by the 127:introduced the facsimile machine in 1843 to 1846. 831:Mechanical techniques are also used in long wave 610:) can just be seen through the lens on the right. 4231:Telecommunications-related introductions in 1925 4222: 2029:Mechanical Television & Illusion Generators 1457:Early Television: A Bibliographic Guide to 1940 1666:, University of Illinois Press, 1995, p. 231. 918:The flying spot method has two disadvantages: 797:(DLP) projectors use an array of tiny (16 μm) 3144: 2105: 985:, an entire flying-spot color studio system. 572:was tested in 1935, and a 180-line system by 1626: 1624: 1512:, Sunday Magazine, September 20, 1907, p. 7. 1495:, Sunday Magazine, September 20, 1907, p. 7. 287:As a 23-year-old German university student, 270: 217: 123:, the transmission of still images by wire. 23:, called a "televisor" in several languages. 4159:Global telecommunications regulation bodies 2119: 2081:WCFL is on the air with Television Programs 1704:, McFarland & Co., Inc., 1987, p. 101. 1157:The worldwide history of telecommunications 606:A color televisor. A test card (the famous 4195: 3151: 3137: 2112: 2098: 1992:The World's Earliest Television Recordings 1590: 1588: 1578:"Radio Shows Far Away Objects in Motion", 1379:, January 30, 1910, p. 20C. (Reprinted in 929:In 1928, Ray Kell from the United States' 907:and amplified to become the video signal. 750:Modern applications of mechanical scanning 3000: 2998: 2024:NBTV Forum - Build Your own Mechanical TV 1856:, in Jones, Eric M.; Glover, Ken (eds.), 1621: 1546: 683:, and then publicly by Farnsworth at the 1656: 1191:List of experimental television stations 989:continue to use a flying spot approach. 954: 884: 785: 762:has now been replaced with super-bright 742:to modulate a focused light beam from a 601: 582: 534:. The station is still operating today. 471: 274: 220:Exposition Universelle et Internationale 190: 65:electronic television technology, using 25: 2034:Television with 4 rotating LED – Strips 1734: 1702:The History of Television, 1880 to 1941 1594: 1585: 1266: 1250:"Giovanni Caselli and the Pantelegraph" 874: 149:in 1873, laying the groundwork for the 4223: 3158: 2995: 2992:Also used in China's DVB-S/S2 network. 2988: 2986: 2044:Early Television Foundation and Museum 1876:National Science and Media Museum blog 1260: 842:techniques are combined with computer 716:'Scophony' mechanical display receiver 3132: 3030: 2131: 2093: 1835:Hawes Mechanical Television Archive, 1131:, A&E Television Networks, 2003, 231:, individually wired to a mechanical 4205: 3031: 1848: 1487:Télévision au moyen de l'électricité 1459:. Taylor & Francis, pp. 13, 22. 1311:, (Saturday, 16 October, 1896), p.3. 922:Actors must perform in near darkness 869: 790:Television machine with 4 LED strips 728:Cathode-Ray Television tube displays 576:started in 1935 at station VE9AK in 2983: 2039:Hawes Mechanical Television Archive 1599:Theremin: Ether Music and Espionage 1423:, Paris, December 11, 1909, p. 451. 597: 13: 1506:"Sending Photographs by Telegraph" 846:in the LaserMAME project. It is a 332:, that made the design practical. 14: 4262: 2012: 2004:Phonovision: The Recovered Images 1817:CBS Field Sequential Color System 1491:Congrès Inographs by Telegraph", 663:electronic television (including 639:A few years after Col-R-Tel, the 362:Baird and his television receiver 114: 69:scanning methods, for example in 4204: 4194: 4185: 4184: 4173: 3794:Free-space optical communication 1329:"Another Electric Distance-Seer" 1024: 992: 355: 339: 1997: 1985: 1964: 1952: 1938: 1927:from the original on 2007-10-15 1913: 1889: 1864: 1829: 1810: 1798: 1776: 1755: 1728: 1715: 1694: 1677: 1664:Zworykin, Pioneer of Television 1652:Springer Science+Business Media 1638: 1572: 1555: 1515: 1479: 1476:Shiers & Shiers, p. 13, 22. 1470: 1455:Shiers, George and May (1997), 1449: 1426: 1402: 1399:, January 2, 1910, pp. 138-139. 1386: 1369: 1335:, September 11, 1909, page 384. 1121: 203:The first demonstration of the 2132: 1358: 1338: 1322: 1300: 1295:1885 Telephane system diagrams 1288: 1242: 1229: 1217: 1201:Television systems before 1940 899:across the subject scene in a 1: 4251:History of telecommunications 2497:Field-sequential color system 2083:WCFL Radio Magazine Fall-1928 1738:A History of Early Television 1725:(London: IEEE, 2000), p. 184. 1211: 1173:, John Wiley and Sons, 2006, 854:displays thus-far described. 616:field-sequential color system 239:. In the receiver, a type of 4180:Telecommunication portal 3961:Telecommunications equipment 3077:Reverse Standards Conversion 1858:Apollo Lunar Surface Journal 1145:, Marshall Cavendish, 2007, 1141:Cavendish, Marshall (Corp), 1095: 559:Reichs-Rundfunk-Gesellschaft 7: 3697:Alexander Stepanovich Popov 1523:"Current Topics and Events" 1206:Narrow-bandwidth television 1196:List of years in television 1184: 894:in the dish-shaped mirrors. 768:narrow-bandwidth television 667:and other camera tubes and 421:. In 1932, he demonstrated 289:Paul Julius Gottlieb Nipkow 10: 4267: 3401:Telecommunications history 1099: 878: 850:-based system, unlike the 736:441-line television system 732:405-line television system 719: 654: 291:proposed and patented the 235:, served as an electronic 164:designed what he called a 107: 103: 47:mechanical scan television 18: 4168: 4110: 4047: 4009:Public Switched Telephone 3969: 3933: 3890: 3831: 3821:telecommunication circuit 3782:Fiber-optic communication 3765: 3527:Francis Blake (telephone) 3474: 3322:Optical telecommunication 3166: 3037: 3026: 2978: 2937: 2864: 2826: 2808: 2755: 2737: 2714: 2696: 2651: 2565: 2523: 2514: 2449: 2378: 2335: 2319: 2303: 2281: 2209: 2169: 2151: 2142: 2138: 2127: 1786:. Early Television Museum 1735:Herbert, Stephen (2004). 1375:"Television on the Way", 1316:December 9, 2018, at the 1268:Withers, William Bramwell 1169:Sarkar, Tapan K. et al., 271:Television demonstrations 3920:Orbital angular-momentum 3357:Satellite communications 3196:Communications satellite 1946:"Ulises Armand Sanabria" 1741:. Taylor & Francis. 1595:Glinsky, Albert (2000). 1143:Inventors and Inventions 795:Digital light processing 311:International World Fair 53:system that relies on a 3799:Molecular communication 3622:Gardiner Greene Hubbard 3451:Undersea telegraph line 3186:Cable protection system 2121:Broadcast video formats 1901:www.earlytelevision.org 1723:Restoring Baird's Image 1533:(2892): 504–508. 1925. 1393:"Television 'In Sight'" 1086:Charles Francis Jenkins 438:Charles Francis Jenkins 188:in Washington in 1896. 75:liquid-crystal displays 3941:Communication protocol 3727:Charles Sumner Tainter 3542:Walter Houser Brattain 3487:Edwin Howard Armstrong 3295:Information revolution 3087:Television transmitter 1582:, June 14, 1925, p. 1. 1090:Ulises Armand Sanabria 1036:This shape created a " 1000:Ulises Armand Sanabria 965: 895: 840:Laser lighting display 791: 754:Since the 1970s, some 611: 594: 477: 449:On December 25, 1925, 436:An American inventor, 284: 218: 200: 39: 4236:Television technology 3915:Polarization-division 3647:Narinder Singh Kapany 3612:Erna Schneider Hoover 3532:Jagadish Chandra Bose 3512:Alexander Graham Bell 3243:online video platform 3072:MPEG transport stream 2899:MPEG-1 Audio Layer II 2462:Mechanical television 2370:Zweikanalton (A2/IGR) 1974:. Earlytelevision.org 1897:"The Scophony System" 1765:. Earlytelevision.org 1690:November 1990, page 5 1438:, IET, 1998, p. 119. 1381:American Broadcasting 1155:Huurdeman, Anton A., 958: 888: 789: 605: 586: 574:Peck Television Corp. 498:Secretary of Commerce 475: 441:In 1925 Jenkins used 381:images in motion, at 278: 194: 110:History of television 43:Mechanical television 29: 3757:Vladimir K. Zworykin 3717:Almon Brown Strowger 3687:Charles Grafton Page 3342:Prepaid mobile phone 3270:Electrical telegraph 3107:Widescreen signaling 3082:Standards conversion 3067:Moving image formats 1410:La vision à distance 1159:, Wiley-IEEE, 2003, 875:Flying spot scanners 641:Apollo Moon missions 494:Whippany, New Jersey 463:Vladimir K. Zworykin 305:had coined the word 170:Nipkow spinning disk 3707:Johann Philipp Reis 3466:Wireless revolution 3428:The Telephone Cases 3285:Hydraulic telegraph 3062:Display motion blur 1851:"Apollo Television" 1849:Wood, Bill (2005), 1837:How Col-R-Tel Works 1685:Popular Photography 1539:1925Natur.115..504. 1408:Henry de Varigny, " 1397:The Literary Digest 1171:History of wireless 1088:, William Peck and 971:Manfred von Ardenne 905:photoelectric cells 881:Flying-spot scanner 698:DuMont Laboratories 659:The advancement of 622:system invented by 505:flying-spot scanner 459:Shizuoka University 162:Ballarat, Australia 3905:Frequency-division 3882:Telephone exchange 3752:Charles Wheatstone 3682:Jun-ichi Nishizawa 3657:Innocenzo Manzetti 3592:Reginald Fessenden 3327:Optical telegraphy 3160:Telecommunications 3113:Analogue TV Topics 2059:2008-05-17 at the 1822:2010-01-05 at the 1721:Donald F. McLean, 1700:Abramson, Albert, 1580:The New York Times 1563:Television in 1932 1510:The New York Times 1493:The New York Times 1415:2016-03-03 at the 1307:Pictures by Wire, 1223:Huurdeman, p. 149 1078:Ernst Alexanderson 966: 896: 792: 685:Franklin Institute 612: 595: 580:, Quebec, Canada. 537:Meanwhile, in the 478: 451:Kenjiro Takayanagi 369:Scottish inventor 303:Constantin Perskyi 285: 201: 174:selenium photocell 135:from 1856 onward. 129:Frederick Bakewell 40: 4218: 4217: 3956:Store and forward 3951:Data transmission 3865:Network switching 3816:Transmission line 3662:Guglielmo Marconi 3627:Internet pioneers 3492:Mohamed M. Atalla 3461:Whistled language 3126: 3125: 3122: 3121: 3022: 3021: 3018: 3017: 3014: 3013: 2904:MPEG Multichannel 2510: 2509: 1710:978-0-89950-284-7 1662:Albert Abramson, 1567:BBC Annual Report 1465:978-0-8240-7782-2 1065:Bell Laboratories 870:Technical aspects 799:electrostatically 706:1939 World's Fair 669:cathode ray tubes 588:Block diagram of 257:Vladimir Zworykin 213:Palace of Justice 143:photoconductivity 4258: 4208: 4207: 4198: 4197: 4188: 4187: 4178: 4177: 4176: 4049:Notable networks 4039:Wireless network 3979:Cellular network 3971:Types of network 3946:Computer network 3833:Network topology 3747:Thomas A. Watson 3602:Oliver Heaviside 3587:Philo Farnsworth 3562:Daniel Davis Jr. 3537:Charles Bourseul 3497:John Logie Baird 3206:Data compression 3201:Computer network 3153: 3146: 3139: 3130: 3129: 3102:Video processing 3032:Technical issues 3028: 3027: 3005: 3002: 2993: 2990: 2521: 2520: 2253:(Color systems: 2181:(Color systems: 2149: 2148: 2140: 2139: 2129: 2128: 2114: 2107: 2100: 2091: 2090: 2007: 2001: 1995: 1989: 1983: 1982: 1980: 1979: 1968: 1962: 1959:Media quotations 1956: 1950: 1949: 1942: 1936: 1935: 1933: 1932: 1917: 1911: 1910: 1908: 1907: 1893: 1887: 1886: 1884: 1883: 1868: 1862: 1861: 1855: 1846: 1840: 1833: 1827: 1814: 1808: 1802: 1796: 1795: 1793: 1791: 1780: 1774: 1773: 1771: 1770: 1763:"VE9AK entry at" 1759: 1753: 1752: 1732: 1726: 1719: 1713: 1698: 1692: 1681: 1675: 1660: 1654: 1642: 1636: 1628: 1619: 1618: 1602: 1592: 1583: 1576: 1570: 1559: 1553: 1552: 1550: 1548:10.1038/115504a0 1519: 1513: 1503: 1497: 1483: 1477: 1474: 1468: 1453: 1447: 1430: 1424: 1406: 1400: 1390: 1384: 1377:Kansas City Star 1373: 1367: 1362: 1356: 1349:Industrial World 1345:"Seeing by Wire" 1342: 1336: 1326: 1320: 1309:The Evening Star 1304: 1298: 1292: 1286: 1285: 1264: 1258: 1257: 1252:. Archived from 1246: 1240: 1233: 1227: 1221: 1115:John Logie Baird 977:. In the 1950s, 931:General Electric 681:Philo Farnsworth 665:image dissectors 620:color television 598:Color television 590:General Electric 516:General Electric 423:ultra-short wave 371:John Logie Baird 359: 343: 297:image rasterizer 265:cathode-ray tube 255:and his student 223: 139:Willoughby Smith 133:Giovanni Caselli 86:John Logie Baird 71:cathode-ray tube 34:, in front of a 4266: 4265: 4261: 4260: 4259: 4257: 4256: 4255: 4221: 4220: 4219: 4214: 4174: 4172: 4164: 4106: 4043: 3965: 3929: 3886: 3835: 3827: 3768: 3761: 3667:Robert Metcalfe 3522:Tim Berners-Lee 3470: 3290:Information Age 3162: 3157: 3127: 3118: 3097:Video on demand 3042:14:9 compromise 3033: 3010: 3009: 3008: 3003: 2996: 2991: 2984: 2974: 2933: 2929:MPEG-H 3D Audio 2860: 2822: 2804: 2751: 2733: 2710: 2692: 2647: 2561: 2506: 2445: 2374: 2331: 2315: 2299: 2277: 2205: 2165: 2134: 2123: 2118: 2087: 2061:Wayback Machine 2054:Scophony System 2015: 2010: 2002: 1998: 1990: 1986: 1977: 1975: 1970: 1969: 1965: 1957: 1953: 1944: 1943: 1939: 1930: 1928: 1919: 1918: 1914: 1905: 1903: 1895: 1894: 1890: 1881: 1879: 1870: 1869: 1865: 1853: 1847: 1843: 1834: 1830: 1824:Wayback Machine 1815: 1811: 1803: 1799: 1789: 1787: 1782: 1781: 1777: 1768: 1766: 1761: 1760: 1756: 1749: 1733: 1729: 1720: 1716: 1699: 1695: 1682: 1678: 1661: 1657: 1643: 1639: 1629: 1622: 1615: 1593: 1586: 1577: 1573: 1560: 1556: 1521: 1520: 1516: 1504: 1500: 1484: 1480: 1475: 1471: 1454: 1450: 1431: 1427: 1417:Wayback Machine 1407: 1403: 1391: 1387: 1374: 1370: 1363: 1359: 1343: 1339: 1333:Literary Digest 1327: 1323: 1318:Wayback Machine 1305: 1301: 1293: 1289: 1265: 1261: 1248: 1247: 1243: 1234: 1230: 1222: 1218: 1214: 1187: 1124: 1104: 1098: 1061:Herbert E. Ives 1027: 995: 883: 877: 872: 752: 724: 718: 657: 600: 593: 481:Herbert E. Ives 367: 366: 365: 364: 363: 360: 352: 351: 344: 273: 145:of the element 141:discovered the 117: 112: 106: 49:is an obsolete 24: 17: 12: 11: 5: 4264: 4254: 4253: 4248: 4243: 4241:Videotelephony 4238: 4233: 4216: 4215: 4213: 4212: 4202: 4192: 4182: 4169: 4166: 4165: 4163: 4162: 4155: 4150: 4145: 4140: 4135: 4134: 4133: 4128: 4120: 4114: 4112: 4108: 4107: 4105: 4104: 4099: 4094: 4089: 4084: 4079: 4074: 4069: 4064: 4059: 4053: 4051: 4045: 4044: 4042: 4041: 4036: 4031: 4026: 4021: 4016: 4011: 4006: 4001: 3996: 3991: 3986: 3981: 3975: 3973: 3967: 3966: 3964: 3963: 3958: 3953: 3948: 3943: 3937: 3935: 3931: 3930: 3928: 3927: 3922: 3917: 3912: 3907: 3902: 3900:Space-division 3896: 3894: 3888: 3887: 3885: 3884: 3879: 3878: 3877: 3872: 3862: 3861: 3860: 3850: 3845: 3839: 3837: 3829: 3828: 3826: 3825: 3824: 3823: 3813: 3812: 3811: 3801: 3796: 3791: 3790: 3789: 3779: 3773: 3771: 3763: 3762: 3760: 3759: 3754: 3749: 3744: 3739: 3737:Camille Tissot 3734: 3729: 3724: 3719: 3714: 3712:Claude Shannon 3709: 3704: 3702:Tivadar Puskás 3699: 3694: 3689: 3684: 3679: 3674: 3672:Antonio Meucci 3669: 3664: 3659: 3654: 3649: 3644: 3642:Charles K. Kao 3639: 3634: 3629: 3624: 3619: 3617:Harold Hopkins 3614: 3609: 3604: 3599: 3594: 3589: 3584: 3579: 3574: 3569: 3564: 3559: 3554: 3549: 3544: 3539: 3534: 3529: 3524: 3519: 3517:Emile Berliner 3514: 3509: 3504: 3499: 3494: 3489: 3484: 3478: 3476: 3472: 3471: 3469: 3468: 3463: 3458: 3456:Videotelephony 3453: 3448: 3447: 3446: 3441: 3431: 3424: 3419: 3413: 3408: 3403: 3398: 3393: 3392: 3391: 3386: 3381: 3371: 3370: 3369: 3359: 3354: 3352:Radiotelephone 3349: 3344: 3339: 3334: 3329: 3324: 3319: 3318: 3317: 3307: 3302: 3297: 3292: 3287: 3282: 3277: 3272: 3267: 3262: 3257: 3256: 3255: 3250: 3245: 3240: 3238:Internet video 3230: 3229: 3228: 3223: 3218: 3213: 3203: 3198: 3193: 3188: 3183: 3178: 3172: 3170: 3164: 3163: 3156: 3155: 3148: 3141: 3133: 3124: 3123: 3120: 3119: 3117: 3116: 3109: 3104: 3099: 3094: 3089: 3084: 3079: 3074: 3069: 3064: 3059: 3052:Digital cinema 3049: 3047:Broadcast-safe 3044: 3038: 3035: 3034: 3024: 3023: 3020: 3019: 3016: 3015: 3012: 3011: 3007: 3006: 2994: 2981: 2980: 2979: 2976: 2975: 2973: 2972: 2967: 2962: 2957: 2952: 2950:Broadcast flag 2947: 2941: 2939: 2938:Hidden signals 2935: 2934: 2932: 2931: 2926: 2921: 2916: 2911: 2906: 2901: 2896: 2891: 2886: 2881: 2870: 2868: 2862: 2861: 2859: 2858: 2853: 2848: 2843: 2838: 2832: 2830: 2824: 2823: 2821: 2820: 2814: 2812: 2806: 2805: 2803: 2802: 2797: 2792: 2787: 2782: 2777: 2772: 2767: 2761: 2759: 2753: 2752: 2750: 2749: 2743: 2741: 2735: 2734: 2732: 2731: 2726: 2720: 2718: 2712: 2711: 2709: 2708: 2702: 2700: 2694: 2693: 2691: 2690: 2685: 2680: 2675: 2674: 2673: 2663: 2657: 2655: 2649: 2648: 2646: 2645: 2644: 2643: 2638: 2628: 2627: 2626: 2621: 2611: 2610: 2609: 2604: 2594: 2593: 2592: 2587: 2582: 2571: 2569: 2563: 2562: 2560: 2559: 2558: 2557: 2547: 2546: 2545: 2540: 2529: 2527: 2518: 2512: 2511: 2508: 2507: 2505: 2504: 2499: 2494: 2489: 2484: 2479: 2474: 2469: 2464: 2459: 2453: 2451: 2447: 2446: 2444: 2443: 2438: 2433: 2428: 2423: 2418: 2413: 2408: 2403: 2398: 2393: 2388: 2382: 2380: 2379:Hidden signals 2376: 2375: 2373: 2372: 2367: 2365:Sound-in-Syncs 2362: 2357: 2352: 2347: 2341: 2339: 2333: 2332: 2330: 2329: 2323: 2321: 2317: 2316: 2314: 2313: 2307: 2305: 2301: 2300: 2298: 2297: 2287: 2285: 2279: 2278: 2276: 2275: 2270: 2215: 2213: 2207: 2206: 2204: 2203: 2198: 2175: 2173: 2167: 2166: 2164: 2163: 2157: 2155: 2146: 2136: 2135: 2125: 2124: 2117: 2116: 2109: 2102: 2094: 2085: 2084: 2078: 2073: 2068: 2063: 2051: 2046: 2041: 2036: 2031: 2026: 2021: 2014: 2013:External links 2011: 2009: 2008: 1996: 1984: 1963: 1951: 1937: 1923:. 2007-10-15. 1912: 1888: 1863: 1841: 1828: 1809: 1797: 1775: 1754: 1747: 1727: 1714: 1693: 1676: 1655: 1637: 1620: 1613: 1584: 1571: 1561:J. L. Baird, " 1554: 1514: 1498: 1478: 1469: 1448: 1425: 1421:L'Illustration 1401: 1385: 1368: 1357: 1337: 1321: 1299: 1287: 1259: 1256:on 2016-01-15. 1241: 1235:Beyer, p. 100 1228: 1215: 1213: 1210: 1209: 1208: 1203: 1198: 1193: 1186: 1183: 1182: 1181: 1167: 1153: 1139: 1123: 1120: 1097: 1094: 1063:at AT&T's 1026: 1023: 994: 991: 987:Laser scanners 927: 926: 923: 879:Main article: 876: 873: 871: 868: 821:photoconductor 751: 748: 720:Main article: 717: 714: 656: 653: 624:Peter Goldmark 599: 596: 587: 501:Herbert Hoover 361: 354: 353: 345: 338: 337: 336: 335: 334: 272: 269: 229:selenium cells 125:Alexander Bain 116: 115:Early research 113: 105: 102: 21:television set 15: 9: 6: 4: 3: 2: 4263: 4252: 4249: 4247: 4244: 4242: 4239: 4237: 4234: 4232: 4229: 4228: 4226: 4211: 4203: 4201: 4193: 4191: 4183: 4181: 4171: 4170: 4167: 4160: 4156: 4154: 4151: 4149: 4146: 4144: 4141: 4139: 4136: 4132: 4129: 4127: 4124: 4123: 4121: 4119: 4116: 4115: 4113: 4109: 4103: 4100: 4098: 4095: 4093: 4090: 4088: 4085: 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Perlman 3690: 3688: 3685: 3683: 3680: 3678: 3675: 3673: 3670: 3668: 3665: 3663: 3660: 3658: 3655: 3653: 3650: 3648: 3645: 3643: 3640: 3638: 3635: 3633: 3630: 3628: 3625: 3623: 3620: 3618: 3615: 3613: 3610: 3608: 3605: 3603: 3600: 3598: 3595: 3593: 3590: 3588: 3585: 3583: 3582:Lee de Forest 3580: 3578: 3577:Thomas Edison 3575: 3573: 3570: 3568: 3567:Donald Davies 3565: 3563: 3560: 3558: 3555: 3553: 3552:Claude Chappe 3550: 3548: 3545: 3543: 3540: 3538: 3535: 3533: 3530: 3528: 3525: 3523: 3520: 3518: 3515: 3513: 3510: 3508: 3505: 3503: 3500: 3498: 3495: 3493: 3490: 3488: 3485: 3483: 3480: 3479: 3477: 3473: 3467: 3464: 3462: 3459: 3457: 3454: 3452: 3449: 3445: 3442: 3440: 3437: 3436: 3435: 3432: 3430: 3429: 3425: 3423: 3420: 3417: 3414: 3412: 3409: 3407: 3404: 3402: 3399: 3397: 3396:Smoke signals 3394: 3390: 3387: 3385: 3382: 3380: 3377: 3376: 3375: 3374:Semiconductor 3372: 3368: 3365: 3364: 3363: 3360: 3358: 3355: 3353: 3350: 3348: 3345: 3343: 3340: 3338: 3335: 3333: 3330: 3328: 3325: 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Burns, 1429: 1422: 1418: 1414: 1411: 1405: 1398: 1394: 1389: 1382: 1378: 1372: 1366: 1361: 1354: 1350: 1346: 1341: 1334: 1330: 1325: 1319: 1315: 1312: 1310: 1303: 1296: 1291: 1283: 1279: 1275: 1274: 1269: 1263: 1255: 1251: 1245: 1239: 1232: 1226: 1220: 1216: 1207: 1204: 1202: 1199: 1197: 1194: 1192: 1189: 1188: 1180: 1179:0-471-71814-9 1176: 1172: 1168: 1166: 1165:0-471-20505-2 1162: 1158: 1154: 1152: 1151:0-7614-7763-2 1148: 1144: 1140: 1138: 1137:0-06-001401-6 1134: 1130: 1127:Beyer, Rick, 1126: 1125: 1119: 1116: 1111: 1109: 1103: 1093: 1091: 1087: 1083: 1079: 1073: 1071: 1066: 1062: 1057: 1053: 1051: 1047: 1043: 1039: 1034: 1032: 1025:Aspect ratios 1022: 1020: 1016: 1011: 1008: 1003: 1001: 993:Larger videos 990: 988: 984: 980: 976: 972: 962: 957: 953: 949: 945: 943: 939: 934: 932: 924: 921: 920: 919: 916: 913: 908: 906: 902: 893: 887: 882: 867: 865: 861: 857: 853: 849: 845: 841: 837: 834: 829: 827: 824:instance, in 822: 818: 817:laser printer 813: 811: 808: 804: 800: 796: 788: 784: 782: 777: 773: 769: 765: 761: 757: 756:amateur radio 747: 745: 741: 737: 733: 729: 723: 713: 711: 710:New York City 707: 703: 699: 695: 690: 686: 682: 678: 677:San Francisco 673: 670: 666: 662: 652: 650: 646: 642: 637: 634: 628: 625: 621: 617: 609: 604: 591: 585: 581: 579: 575: 571: 566: 564: 560: 555: 551: 548: 544: 543:Léon Theremin 540: 535: 533: 529: 525: 521: 517: 512: 510: 506: 502: 499: 495: 491: 486: 482: 474: 470: 468: 464: 460: 456: 452: 447: 444: 439: 434: 432: 428: 424: 420: 416: 412: 408: 407:Bernard Natan 404: 399: 394: 393:Theodore Case 389: 384: 380: 376: 372: 358: 349: 342: 333: 331: 330:Lee de Forest 327: 323: 320: 316: 312: 308: 304: 300: 298: 294: 290: 282: 277: 268: 266: 262: 258: 254: 249: 247: 242: 238: 234: 230: 225: 222: 221: 214: 210: 206: 205:instantaneous 198: 193: 189: 187: 183: 179: 175: 171: 167: 163: 159: 154: 152: 151:selenium cell 148: 144: 140: 136: 134: 130: 126: 122: 111: 101: 99: 94: 92: 87: 82: 80: 76: 72: 68: 67:electron beam 64: 60: 56: 52: 48: 44: 37: 33: 28: 22: 3892:Multiplexing 3767:Transmission 3732:Nikola Tesla 3722:Henry Sutton 3677:Samuel Morse 3607:Robert Hooke 3572:Amos Dolbear 3507:John Bardeen 3426: 3406:Telautograph 3310:Mobile phone 3265:Edholm's law 3248:social media 3181:Broadcasting 2653:MPEG-2 Video 2461: 2191:Clear-Vision 2086: 1999: 1987: 1976:. 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In 1939, 661:vacuum tube 608:test card F 547:interlacing 490:copper wire 443:Nipkow disk 388:Nipkow disk 383:Selfridge's 375:Nipkow disk 322:vacuum tube 293:Nipkow disk 281:Nipkow disk 182:Kerr effect 63:vacuum tube 32:Nipkow disk 4225:Categories 4138:Antarctica 4097:Toasternet 4019:Television 3502:Paul Baran 3434:Television 3418:(teletype) 3411:Telegraphy 3389:transistor 3367:Phryctoria 3337:Photophone 3315:Smartphone 3305:Mass media 2955:Captioning 2757:MPEG-4 AVC 2525:Interlaced 2450:Historical 2386:Captioning 2345:BTSC (MTS) 2320:1250 lines 2304:1125 lines 2133:Television 1978:2010-03-02 1931:2021-03-12 1906:2024-04-22 1882:2024-04-21 1769:2010-03-02 1648:, page 220 1212:References 1100:See also: 1068:people. A 892:phototubes 862:emulation 647:and later 618:. The CBS 485:Frank Gray 379:silhouette 319:amplifying 307:television 233:commutator 108:See also: 77:(LCD) and 55:mechanical 51:television 4122:Americas 4111:Locations 4082:Internet2 3843:Bandwidth 3547:Vint Cerf 3444:streaming 3422:Telephone 3362:Semaphore 3253:streaming 3092:Test card 2765:ATSC A/72 2671:DVB 3D-TV 2283:819 lines 2211:625 lines 2171:525 lines 2153:405 lines 2019:Televisor 1096:Recording 1046:landscape 981:marketed 844:emulation 760:neon lamp 514:In 1928, 419:The Derby 398:scan line 251:In 1911, 241:Kerr cell 166:telephane 156:In 1885, 121:facsimile 98:televisor 36:neon lamp 4190:Category 4077:Internet 4067:CYCLADES 3984:Ethernet 3934:Concepts 3858:terminal 3809:wireless 3632:Bob Kahn 3475:Pioneers 3300:Internet 3191:Cable TV 3004:Defunct. 2970:Teletext 2836:ATSC 3.0 2492:567-line 2487:455-line 2482:441-line 2477:375-line 2472:343-line 2467:180-line 2457:Pre-1940 2411:Teletext 2291:System E 2219:System B 2179:System M 2161:System A 2057:Archived 1925:Archived 1820:Archived 1413:Archived 1314:Archived 1282:9436501W 1270:(1887). 1238:machine. 1185:See also 1042:portrait 1038:portrait 1015:441-line 1007:Scophony 983:Vitascan 975:telecine 961:(bottom) 938:Al Smith 912:arc lamp 864:software 833:infrared 722:Scophony 578:Montreal 172:system, 147:selenium 4210:Commons 4200:Outline 4153:Oceania 4072:FidoNet 4057:ARPANET 3870:circuit 3439:digital 3168:History 2851:ISDB-S3 2800:MobaHo! 2747:MobaHo! 2516:Digital 2263:PALplus 1569:, 1933. 1535:Bibcode 783:laser. 655:Decline 403:Glasgow 348:(right) 263:tube" ( 104:History 4148:Europe 4118:Africa 4102:Usenet 4062:BITNET 3999:Mobile 3875:packet 3384:MOSFET 3379:device 3176:Beacon 2924:HE-AAC 2846:HD DMB 2391:CGMS-A 2327:HD-MAC 2187:NTSC-J 2144:Analog 1745: 1708: 1670: 1611: 1527:Nature 1463: 1442: 1280: 1177: 1163: 1149: 1135: 979:DuMont 901:raster 852:raster 848:vector 726:Early 694:Philco 563:Berlin 326:triode 324:, the 237:retina 4246:Video 4131:South 4126:North 4087:JANET 4024:Telex 4014:Radio 3853:Nodes 3848:Links 3769:media 3347:Radio 3332:Pager 3260:Drums 3226:video 3221:image 3211:audio 2866:Audio 2818:ABS-S 2790:SBTVD 2729:ABS-S 2688:ABS-S 2631:UHDTV 2624:1080p 2555:1080i 2355:NICAM 2337:Audio 2267:SECAM 2259:PAL-N 2201:B-MAC 2195:PAL-M 1854:(PDF) 1607:–45. 1365:Ibid. 856:Laser 570:Paris 415:Baird 411:Pathé 328:, by 315:Paris 261:Braun 246:pixel 197:pixel 91:W2XAB 59:video 4143:Asia 4029:UUCP 3989:ISDN 2960:CPCM 2914:LPCM 2884:AC-4 2874:AC-3 2856:DTMB 2810:AVS2 2795:1seg 2780:DTMB 2770:CMMB 2724:DTMB 2716:AVS+ 2706:CMMB 2683:DTMB 2678:ISDB 2661:ATSC 2619:720p 2614:HDTV 2607:576p 2602:480p 2597:EDTV 2590:288p 2585:240p 2580:1seg 2575:LDTV 2550:HDTV 2543:576i 2538:480i 2533:SDTV 2502:OSKM 2431:VITC 2421:VEIL 2350:EIAJ 2311:MUSE 2183:NTSC 1792:2012 1743:ISBN 1706:ISBN 1668:ISBN 1609:ISBN 1461:ISBN 1440:ISBN 1175:ISBN 1161:ISBN 1147:ISBN 1133:ISBN 1044:and 860:MAME 764:LEDs 696:and 633:NTSC 532:WRGB 520:W2XB 503:. 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