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Television systems before 1940

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Television systems before 1940

A number of experimental and broadcast pre World War II television systems were tested. The first ones were mechanical based (mechanical television) and of very low resolution, sometimes with no sound. Later TV systems were electronic (electronic television).

France

  • France 1930 (mechanical): 30 lines, 12.5 frame/s
  • France 1932 (mechanical): 60 lines, 12.5 frame/s, 3:7 vertical aspect ratio, vertical scanning ~35x60 pixels per frame, sound, live images
  • France 1935-1936: 375 lines
  • France 1935-1939 (electronic): 455 lines
  • France 1943-1956 (electronic): 441 lines

Germany

  • Doberitz 1932 (mechanical): 48 lines, 25 frame/s, 4:3 horizontal aspect ratio, ~64x48 pixels per frame, sound, talking movies
  • Berlin R.P.Z. 1932 (mechanical): 60 lines, 25 frame/s, 4:3 horizontal aspect ratio, ~83x60 pixels per frame, test movies and live images
  • Germany 1932: 90 lines
  • Germany 1935: 180 lines
  • Germany 1937: 441 lines, 25 frame/s, line frequency 11025 Hz. Vision 46.0 MHz Sound 43.2 MHz.
  • Germany 1940: 1000 lines signal projection, no glass screen but projection screen (successful experiments in Reichspost laboratories, but no mass production, note that in Germany public telegraphy, telephone, and radio services were subject to the Reichspostministerium since the early 20th century, and TV was regarded a postal issue as well until the 1980s)

Netherlands

  • Netherlands 1930s: 441 lines, 25 frame/s, line frequency 11025 Hz
  • Late 1940s: 567 lines

Poland

  • Warsaw 1937 (mechanical): 120 lines, test movies and live images from a studio
  • Electronic TV (343 lines) was under development and was publicly demonstrated during the Radio Exhibition in Warsaw in August 1939, regular operations planned to start at the beginning of 1940, work stopped because of the outbreak of World War II.

Switzerland

  • Switzerland 1932 (mechanical): 30 lines, 16.6 frame/s, 4:3 horizontal aspect ratio, ~40x30 pixels per frame, test movies and live images

Italy

During the 1930s there were also experimental transmissions from the Vatican - but further details are unknown

  • Italy 1932 (mechanical): 60 lines, 20 frame/s, 4:3 horizontal aspect ratio, ~45x60 pixels per frame, test movies and live images
  • Italy 1937 (electronic): 375 lines, 25 frame/s, 4:3 horizontal aspect ratio, daily from Rome, between 6pm and 9.30pm on 6.9 meters with a power of 2 kW
  • Italy 1939 (electronic): 441 lines, 25 frame/s, 4:3 horizontal aspect ratio, regular service from Rome and Milan. 2 kW transmission power on VHF 45 MHz

UK

Mechanical

  • England 1926 (Baird mechanical): 30 lines, 5 frame/s, black-and-white experimental transmissions
  • England 1928 (Baird mechanical): 30 lines, 5 frame/s, first experimental color TV transmissions
  • London 1932 (Baird mechanical) : 30 lines, 12.5 frame/s, 3:7 vertical aspect ratio, vertical scanning, ~70x30 pixels per frame, sound, live TV from studio
  • England 1936 (Baird): 240 lines, 25 frame/s, line frequency 6000 Hz, used from November 1936 to February 1937

Electronic

  • UK (1936, EMI): 405 lines / 50 Hz. Used by the BBC Alexandra Palace television station initially from November 1936 to 1939 and then 1945 to 1985 (interruption due to 2nd World War).
    • The EMI 405 lines system was the first to have an ITU System Letter Designation.
    • The EMI system is officially known as System A. As the EMI system predates PAL, there is no PAL designator in the ITU television system table.

USSR

  • USSR 1932 (mechanical): 30 lines, 12.5 frame/s, 4:3 horizontal aspect ratio, ~40x30 pixels per frame, test movies and live images
  • USSR 1938 (electronic): 343 lines, 25 frame/s, 4:3 horizontal aspect ratio, later (1940) replaced to 441 lines, 25fps. (RCA made equipment used).

North America

  • USA 1933: 240 lines
  • USA 1936: 343 lines; limited public demonstrations in New York City (RCA) and Philadelphia (Philco). Field tests in Los Angeles used various line systems, but adopted RCA's 441 lines system by 1938.
  • USA 1938-9: First TV receivers sold on a very limited basis, mostly in New York. Manufacturers included RCA, General Electric, DuMont, and Andrea.
  • USA 1937-1941: 441 lines @ 30 f.p.s.(RCA) and 605 lines (Proposed by Philco).
  • USA 1941-2009: 525 line System-M officially mandated on July 1, 1941 when the Federal Communications Commission issued the first commercial licenses. In use until 2009, when the FCC mandated cessation of analog broadcasting and conversion to the current 1080-line ATSC digital system. This system is still in use in the USA, by a dwindling number of low-power (LPTV) stations who may operate in System-M through August, 2015. System-M is still widely used in closed circuits to send content from video game devices, cable and satellite services, VCR units and digital converter boxes to analog receivers.

See also

Individual television stations

Broadcast television systems

Related topics in television systems

External links

  • (in German) Rolf Wigand: Technische Beschreibung des E 1 (Zeitgenössischer Artikel in „Radio-Mentor", pdf 295 kB)
  • (in German) Eckhard Etzold: Ausführliche Webseite mit vielen Fotos sowie Schaltbild des E 1


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