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This is a list of pre-World War II television stations of the 1920s and 1930s. Most of these experimental stations were located in Europe (notably in the United Kingdom, France, Germany, Italy, Poland, the Netherlands, and Russia), Australia, Canada, and the United States. Some present-day broadcasters trace their origins to these early stations.
All television licenses in the United States were officially "experimental" before July 1941, as the NTSC television standard had yet to be developed, and some American television broadcasters continued operating under experimental licenses as late as 1947, although by then they were using the same technical standards as their commercial brethren.
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Call sign (original) | Call sign (current) | Frequency* | Channel (current) | Location (city) | On air | Owner (original) | Original broadcast system | Current broadcast system |
---|---|---|---|---|---|---|---|---|
Baird Television Development Company Ltd [1] via BBC transmitter 2LO [ citation needed ] | 361 meters 831 kHz [2] | London, England, United Kingdom | 1926–1935 [ citation needed ] | British Broadcasting Company | Mechanical television 30 lines 25 frame/s | [ dubious – discuss ] | ||
W2XB (also branded as WGY-TV from its sister radio station) | WRGB | 2.15 MHz | 6 | Schenectady Albany, New York, United States | May 10, 1928 – present | General Electric Co. | Mechanical television 24 (later 48) lines/21 frame/s | NTSC-M from 1942–2009; now ATSC digital. |
W1XAY (also branded as WLEX from its sister radio station) | 3.5 MHz | Lexington, Massachusetts, United States | June 14, 1928– March 1930 | The Boston Post | Mechanical television 48 lines/18 frame/s | |||
W3XK | 1.605 MHz & 6.42 MHz, later 2.00–2.10 MHz | Wheaton Washington, D.C., United States | July 2, 1928– 1932 | Charles Jenkins Laboratories | Mechanical television 48 lines | |||
W2XAL (also branded as WRNY from its sister radio station) | New York City, New York, United States | August 13, 1928– 1929 | Experimenter Publishing | Mechanical television 48 lines | ||||
W1WX (later became W1XAV) | 2.12 MHz | Boston, Massachusetts, United States | Spring 1929–1931 | Shortwave and Television Laboratory | Mechanical television 48 & 60 lines/15 frame/s | |||
W2XBS | WNBC | 2.75–2.85 MHz | Formerly Channel 1; moved to VHF Channel 4 from 1946–2009 (remains PSIP virtual channel); allocated to digital channel 28 from 1999–2018; moved to channel share with WNJU on channel 36 from 2018–present | New York City, New York, United States | 1929–1932, 1936–present | National Broadcasting Company | Mechanical television 60 lines/20 frame/s | 1941–2009, NTSC-M; now ATSC digital |
3UZ. Experiments carried out on the radio station after it had officially closed down for the night. [3] | 930 kHz | Melbourne, Victoria, Australia | 1929 | Oliver John Nilsen | Mechanical television | |||
3DB. Experiments carried out on the radio station after it had officially closed down for the night. [3] | 1180 kHz | Melbourne, Victoria, Australia | 1929 | The Herald and Weekly Times | Mechanical television | |||
W9XAP | WNBQ-TV (1948–1964) [4] now WMAQ-TV | VHF Channel 5 | Chicago, Illinois, United States | August 27, 1930– August 1933. 1948-present. [5] [6] [7] [8] [9] | National Broadcasting Company | Mechanical television | 1948–2009 NTSC-M; now ATSC digital | |
VE9EC | 41 MHz | Montreal, Quebec, Canada | 1931–1935 | La Presse and CKAC radio | Mechanical television 60–150 lines | |||
W6XAO | KCBS-TV | Formerly on Channel 1, now VHF Channel 2 | Los Angeles, California, United States | June 1931– 1933, 1937–1948 as experimental Don Lee station; May 6, 1948– present | Don Lee | Mechanical television, film only, 80 lines/20 frame/s | 1948–2009, NTSC-M; now ATSC digital | |
Amateur radio station 4CM [10] | 136 metres | Brisbane, Queensland, Australia | 1934 | Dr Val McDowall | Early experiments with electronic television | |||
W6XYZ | KTLA-TV | Formerly on Channel 4, now VHF Channel 5 | Los Angeles, California, United States | June 1942– 1946 experimental, Jan. 22, 1947– present | Paramount | 1947–2009, NTSC-M, now ATSC digital | ||
W2XAB | WCBS-TV | 2.1–2.2 MHz | Now VHF Channel 2 | New York City, New York, United States | July 31, 1931– February 1933, 1939–present | Columbia Broadcasting System | Mechanical television 60 lines/20 frame/s | 1941–2009, NTSC-M, now ATSC digital |
W2XWV | WNYW | Channel 4 (1938–1944), Channel 5 (1944 – present) | New York City, New York, United States | 1938– present | Allen B. DuMont | Unknown | 1944–2009 NTSC-M, now ATSC digital | |
W3XE | WPTZ (now KYW-TV) | – | VHF Channel 3 | Philadelphia, Pennsylvania, United States | 1932–present | Philco Corporation | Mechanical television | 1941–2009, NTSC-M, now ATSC digital |
W9XBK | WBKB (now WBBM-TV) | Formerly on Channel 4, then on VHF Channel 2, Now on VHF Channel 12 | Chicago, Illinois, United States | 1940–present | Balaban & Katz | 1944–2009, NTSC-M, now ATSC digital | ||
W9XZV | Later KS2XBS (Phonevision experimental on Channel 2) | VHF Channel 1 | Chicago, Illinois, United States | 1939–1953 | ||||
2LO (BBC Television Service) | BBC One | 361 meters 831 kHz [2] | UHF (Channels 21–68, throughout UK) | London, England, United Kingdom | August 22, 1932– September 11, 1935 | British Broadcasting Corporation | Mechanical television 30 lines/12.5 frame/s | Now DVB |
BBC Television Service (Alexandra Palace) | BBC One | 45 MHz [11] | UHF (Channels 21–68, throughout UK and on Astra 2D satellite) | London, England, United Kingdom | November 1936– September 3, 1939, June 7, 1946 – present | British Broadcasting Corporation | Mechanical television 240 lines (Baird system) and electronic television 405 line (Marconi-EMI system)/25 frame/s | Now DVB |
EIAR – Stazione sperimentale radiovisione di Monte Mario | RAI – Radiotelevisione Italiana | 40.54 MHz (audio), 44.12 MHz (video) | VHF (channel 9) and UHF (channels 25, 26, 30 and 40) | Rome, Italy | July 22, 1939– May 10, 1940 | Electronic television 441 lines / 21 to 42 frame/s. | Now DVB | |
EIAR – Stazione sperimentale radiovisione Torre Littoria (now Torre Branca) | 40.50 MHz (audio), 44.00 MHz (video) | Milan, Italy | April 12–28, 1940 | Electronic television 441 lines / 21 to 42 frame/s. | ||||
Radiovision PTT (1935) later Paris Television (1943) then RTF (1946) (Eiffel Tower) | TF1 | 37 MHz (180 & 455 lines) later 42–46 MHz (441 lines) | UHF Channels 21–69 (System L + DVB throughout France and FTA on AB3 satellite) | Paris, France | November 1935 – 1937 (60 lines, then 180 lines) later 1938–1939 (455 lines) then 1943–1956 (441 lines) | Ministry of Information | Mechanical television 60 then 180 line later electronic television 455 then 441 line/25 frame/s | Now DVB |
Fernsehsender Paul Nipkow | Berlin Potsdam, Germany | 1935–1944 (tests started in 1929) | Deutscher Fernseh-Rundfunk | Electronic television 180 lines/25 frame/s/50 fields/sec (started broadcasting in 441 lines in mid-1937) | ||||
Moscow test broadcasting station МТЦ (from Shukhov tower) | LW band | Moscow, Soviet Union, now Russia | 1931–1941 | Mechanical television | ||||
USSR TV (ТВ СССР) | Первый канал | 49.75 MHz (video) 56.25 MHz (audio) | TV channels:R1 (441 lines 25 fps) | Moscow, USSR, now Russia | 1938–1941, 1945-1949 | Ministry of Culture | Electronic television | Now SECAM, PAL also DVB |
Doświadczalna Stacja Telewizyjna | Telewizja Polska | TVP channels: TVP1, TVP2, etc. | Warsaw, Poland | 1935–1939 (test broadcasting: 1937–38) | Mechanical television | Now PAL and DVB | ||
Call sign (original) | Call sign (current) | Frequency* | Channel (current) | Location (city) | On air | Owner (original) | Original broadcast system | Current broadcast system |
NTSC is the first American standard for analog television, published and adopted in 1941. In 1961, it was assigned the designation System M. It is also known as EIA standard 170.
A television channel, or TV channel, is a terrestrial frequency or virtual number over which a television station or television network is distributed. For example, in North America, channel 2 refers to the terrestrial or cable band of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video (VSB) and 59.75 MHz for analog audio (FM), or 55.31 MHz for digital ATSC (8VSB). Channels may be shared by many different television stations or cable-distributed channels depending on the location and service provider
Terrestrial television or over-the-air television (OTA) is a type of television broadcasting in which the content is transmitted via radio waves from the terrestrial (Earth-based) transmitter of a TV station to a TV receiver having an antenna. The term terrestrial is more common in Europe and Latin America, while in Canada and the United States it is called over-the-air or simply broadcast. This type of TV broadcast is distinguished from newer technologies, such as satellite television, in which the signal is transmitted to the receiver from an overhead satellite; cable television, in which the signal is carried to the receiver through a cable; and Internet Protocol television, in which the signal is received over an Internet stream or on a network utilizing the Internet Protocol. Terrestrial television stations broadcast on television channels with frequencies between about 52 and 600 MHz in the VHF and UHF bands. Since radio waves in these bands travel by line of sight, reception is generally limited by the visual horizon to distances of 64–97 kilometres (40–60 mi), although under better conditions and with tropospheric ducting, signals can sometimes be received hundreds of kilometers distant.
The FM broadcast band is a range of radio frequencies used for FM broadcasting by radio stations. The range of frequencies used differs between different parts of the world. In Europe and Africa and in Australia and New Zealand, it spans from 87.5 to 108 megahertz (MHz) - also known as VHF Band II - while in the Americas it ranges from 88 to 108 MHz. The FM broadcast band in Japan uses 76 to 95 MHz, and in Brazil, 76 to 108 MHz. The International Radio and Television Organisation (OIRT) band in Eastern Europe is from 65.9 to 74.0 MHz, although these countries now primarily use the 87.5 to 108 MHz band, as in the case of Russia. Some other countries have already discontinued the OIRT band and have changed to the 87.5 to 108 MHz band.
Multichannel Television Sound (MTS) is the method of encoding three additional audio channels into analog 4.5 MHz audio carriers on System M and System N. It was developed by the Broadcast Television Systems Committee, an industry group, and sometimes known as BTSC as a result.
Broadcasttelevision systems are the encoding or formatting systems for the transmission and reception of terrestrial television signals.
Amateur television (ATV) is the transmission of broadcast quality video and audio over the wide range of frequencies of radio waves allocated for radio amateur (Ham) use. ATV is used for non-commercial experimentation, pleasure, and public service events. Ham TV stations were on the air in many cities before commercial television stations came on the air. Various transmission standards are used, these include the broadcast transmission standards of NTSC in North America and Japan, and PAL or SECAM elsewhere, utilizing the full refresh rates of those standards. ATV includes the study of building of such transmitters and receivers, and the study of radio propagation of signals travelling between transmitting and receiving stations.
The following tables show the frequencies assigned to analog broadcast television channels in various regions of the world, along with the ITU letter designator for the system used. The frequencies shown are for the analog video and audio carriers. The channel itself occupies several megahertz of bandwidth. For example, North American channel 1 occupies the spectrum from 44 to 50 MHz. See Broadcast television systems for a table of signal characteristics, including bandwidth, by ITU letter designator. Analog television broadcasts have been phased out in most regions, having been replaced by digital television broadcasts.
Narrow-bandwidth television (NBTV) is a type of television designed to fit into a channel narrower than the standard bandwidth used for official television standards.
WSCR – branded 670 The Score – is a commercial sports radio station licensed to serve Chicago, Illinois, and the Chicago metropolitan area. Owned by Audacy, Inc., WSCR is a clear-channel station with extended nighttime range in most of the Central United States and part of the Eastern United States. WSCR is the Chicago affiliate for the BetQL Network, Infinity Sports Network, the Fighting Illini Sports Network and the NFL on Westwood One Sports; the flagship station for the Chicago Cubs and Chicago Bulls radio networks; and the home of radio personalities David Haugh and Matt Spiegel.
The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting. The number of television lines influences the image resolution, or quality of the picture.
WLLH is a commercial radio station in Lawrence, Massachusetts, serving the Merrimack Valley region. The station is owned by Gois Broadcasting, LLC, and airs a tropical music radio format. The transmitter site is on Common Street, near the Lawrence Police Department Headquarters.
Apex radio stations was the name commonly given to a short-lived group of United States broadcasting stations, which were used to evaluate transmitting on frequencies that were much higher than the ones used by standard amplitude modulation (AM) and shortwave stations. Their name came from the tall height of their transmitter antennas, which were needed because coverage was primarily limited to local line-of-sight distances. These stations were assigned to what at the time were described as "ultra-high shortwave" frequencies, between roughly 25 and 44 MHz. They employed amplitude modulation (AM) transmissions, although in most cases using a wider bandwidth than standard broadcast band AM stations, in order to provide high fidelity sound with less static and distortion.
A number of experimental and broadcast pre World War II television systems were tested. The first ones were mechanical based and of very low resolution, sometimes with no sound. Later TV systems were electronic.
Band I is a range of radio frequencies within the very high frequency (VHF) part of the electromagnetic spectrum. The first time there was defined "for simplicity" in Annex 1 of "Final acts of the European Broadcasting Conference in the VHF and UHF bands - Stockholm, 1961". Band I ranges from 47 to 68 MHz for the European Broadcasting Area, and from 54 to 88 MHz for the Americas and it is primarily used for television broadcasting in compliance with ITU Radio Regulations. With the transition to digital TV, most Band I transmitters have already been switched off.
441-line is the number of scan lines in some early electronic monochrome analog television systems. Systems with this number of lines were used with 25 interlaced frames per second in France from 1937 to 1956, Germany from 1939 to 1943, Italy from 1939 to 1940, Japan in 1939, as well as by RCA in the United States with 30 interlaced frames per second from 1938 to 1941. Broadcasts were planned in Finland for 1940, but eventually cancelled due to World War II. Some experiments with a similar system were carried out on the USSR in the 1930s.
CCIR System B was the 625-line VHF analog broadcast television system which at its peak was adopted by more than one hundred countries, either with PAL or SECAM colour. It is usually associated with CCIR System G for UHF broadcasts.
CCIR System A was the 405-line analog broadcast television system adopted in the UK and Ireland. System A service started in 1936 and was discontinued in 1985.
CCIR System I is an analogue broadcast television system. It was first used in the Republic of Ireland starting in December 1961 as the 625-line broadcasting standard to be used on VHF Band I and Band III, sharing Band III with 405-line System A signals radiated in the north and east of the country. The Republic of Ireland slowly extended its use of System I onto the UHF bands.
London (2LO), Nov 1922, 361m
A high power transmitter at 45 MHz with a bandwidth of some 3 MHz was edge of technology in the 1930's