Programming is broadcast by television stations, sometimes called "channels", as stations are licensed by their governments to broadcast only over assigned channels in the television band. At first, terrestrial broadcasting was the only way television could be widely distributed, and because bandwidth was limited, i.e., there were only a small number of channels available, government regulation was the norm.
In the U.S., the Federal Communications Commission (FCC) allowed stations to broadcast advertisements beginning in July 1941, but required public service programming commitments as a requirement for a license. By contrast, the United Kingdom chose a different route, imposing a television license fee on owners of television reception equipment to fund the British Broadcasting Corporation (BBC), which had public service as part of its Royal Charter.
United Kingdom
The first British television broadcast was made by Baird Television's electromechanical system over the BBC radio transmitter in September 1929. Baird provided a limited amount of programming five days a week by 1930. During this time, Southampton earned the distinction of broadcasting the first-ever live television interview, which featured Peggy O'Neil, an actress and singer from Buffalo, New York. On August 22, 1932, BBC launched its own regular service using Baird's 30-line electromechanical system, continuing until September 11, 1935. On November 2, 1936 the BBC began broadcasting a dual-system service, alternating between Marconi-EMI's 405-line standard and Baird's improved 240-line standard, from Alexandra Palace in London, making the BBC Television Service (now BBC One) the world's first regular high-definition television service. The government, on advice from a special advisory committee, decided that Marconi-EMI's electronic system gave the superior picture, and the Baird system was dropped in February 1937. TV broadcasts in London were on the air an average of four hours daily from 1936 to 1939. There were 12,000 to 15,000 receivers. Some sets in restaurants or bars might have 100 viewers for sport events (Dunlap, p56).The outbreak of the Second World War caused the BBC service to be abruptly suspended on September 1, 1939, immediately after announcing the afternoon's programmes, so that transmissions could not be used as a beacon to guide enemy aircraft to London. It resumed, again from Alexandra Palace on June 7, 1946 after the end of the war, showing a cartoon which had been the last programme broadcast before the war. At the end of 1947 there were 54,000 licensed television receivers, compared with 44,000 television sets in the United States at that time.
The first transatlantic television signal was sent in 1928 from London to New York by the Baird Television Development Company/Cinema Television, although this signal was not broadcast to the public. The first live satellite signal to Britain from the United States was broadcast via the Telstar satellite on July 23, 1962.
The first live broadcast from the European continent was made on August 27, 1950.
United StatesThe first regularly scheduled television service in the United States began on July 2, 1928. The Federal Radio Commission authorized C.F. Jenkins to broadcast from experimental station W3XK in Wheaton Maryland, a suburb of Washington, D.C. For at least the first eighteen months, 48-line silhouette images from motion picture film were broadcast, although beginning in the summer of 1929 he occasionally broadcast in halftones.
Hugo Gernsback's New York City radio station began a regular, if limited, schedule of live television broadcasts on August 14, 1928, using 48-line images. Working with only one transmitter, the station alternated radio broadcasts with silent television images of the station's call sign, faces in motion, and wind-up toys in motion. Speaking later that month, Gernsback downplayed the broadcasts, intended for amateur experimenters. "In six months we may have television for the public, but so far we have not got it." Gernsback also published Television, the world's first magazine about the medium.
General Electric's experimental station in Schenectady, New York, on the air sporadically since January 13, 1928, was able to broadcast reflected-light, 48-line images via shortwave as far as Los Angeles, and by September was making four television broadcasts weekly. It is considered to be the direct predecessor of current television station WRGB. The Queen's Messenger, a one-act play broadcast on September 11, 1928, was the world's first live drama on television.
Radio giant RCA began daily experimental television broadcasts in New York City in March 1929 over station W2XBS, the predecessor of current television station WNBC. The 60-line transmissions consisted of pictures, signs, and views of persons and objects. Experimental broadcasts continued to 1931.
General Broadcasting System's WGBS radio and W2XCR television aired their regular broadcasting debut in New York City on April 26, 1931, with a special demonstration set up in Aeolian Hall at Fifth Avenue and Fifty-fourth Street. Thousands waited to catch a glimpse of the Broadway stars who appeared on the six-inch (15 cm) square image, in an evening event to publicize a weekday programming schedule offering films and live entertainers during the four-hour daily broadcasts. Appearing were boxer Primo Carnera, actors Gertrude Lawrence, Louis Calhern, Frances Upton and Lionel Atwill, WHN announcer Nils Granlund, the Forman Sisters, and a host of others.
CBS's New York City station W2XAB began broadcasting their first regular seven days a week television schedule on July 21, 1931, with a 60-line electromechanical system. The first broadcast included Mayor Jimmy Walker, the Boswell Sisters, Kate Smith, and George Gershwin. The service ended in February 1933. Don Lee Broadcasting's station W6XAO in Los Angeles went on the air in December 1931. Using the UHF spectrum, it broadcast a regular schedule of filmed images every day except Sundays and holidays for several years.
By 1935, low-definition electromechanical television broadcasting had ceased in the United States except for a handful of stations run by public universities that continued to 1939. The Federal Communications Commission (FCC) saw television in the continual flux of development with no consistent technical standards, hence all such stations in the U.S. were granted only experimental and non-commercial licenses, hampering television's economic development. Just as importantly, Philo Farnsworth's August 1934 demonstration of an all-electronic system at the Franklin Institute in Philadelphia pointed out the direction of television's future.
On June 15, 1936, Don Lee Broadcasting began a one month-long demonstration of high definition (240+ line) television in Los Angeles on W6XAO (later KTSL) with a 300-line image from motion picture film. By October, W6XAO was making daily television broadcasts of films. RCA and its subsidiary NBC demonstrated in New York City a 343-line electronic television broadcast, with live and film segments, to its licensees on July 7, 1936, and made its first public demonstration to the press on November 6. Irregularly scheduled broadcasts continued through 1937 and 1938. Regularly scheduled electronic broadcasts began in April 1938 in New York (to the second week of June, and resuming in August) and Los Angeles. NBC officially began regularly scheduled television broadcasts in New York on April 30, 1939 with a broadcast of the opening of the 1939 New York World's Fair. By June 1939, regularly scheduled 441-line electronic television broadcasts were available in New York City and Los Angeles, and by November on General Electric's station in Schenectady. From May through December 1939, the New York City NBC station (W2XBS) of General Electric broadcast twenty to fifty-eight hours of programming per month, Wednesday through Sunday of each week. The programming was 33% news, 29% drama, and 17% educational programming, with an estimated 2,000 receiving sets by the end of the year, and an estimated audience of five to eight thousand. A remote truck could cover outdoor events from up to 10 miles (16 km) away from the transmitter, which was located atop the Empire State Building. Coaxial cable was used to cover events at Madison Square Garden. The coverage area for reliable reception was a radius of 40 to 50 miles (80 km) from the Empire State Building, an area populated by more than 10,000,000 people (Lohr, 1940).
The FCC adopted NTSC television engineering standards on May 2, 1941, calling for 525 lines of vertical resolution, 30 frames per second with interlaced scanning, 60 fields per second, and sound carried by frequency modulation. Sets sold since 1939 which were built for slightly lower resolution could still be adjusted to receive the new standard. (Dunlap, p31). The FCC saw television ready for commercial licensing, and the first such licenses were issued to NBC and CBS owned stations in New York on July 1, 1941, followed by Philco's station WPTZ in Philadelphia. The first advertising to appear on American television occurred on the afternoon of July 1, 1941 when New York NBC station WNBT, now WNBC, broadcast a test pattern modified to look like a clock, with the words "Bulova Watch Time" in the lower right quadrant. Picture at: http://www.earlytelevision.org/images/rca_bulova_ad-1.jpg link title The image appeared just prior to that afternoon's telecast of a Brooklyn Dodgers game live from Ebbets Field. After the U.S. entry into World War II, the FCC reduced the required minimum air time for commercial television stations from 15 hours per week to 4 hours. Most TV stations suspended broadcasting. On the few that remained, programs included entertainment such as boxing and plays, events at Madison Square Garden, and illustrated war news as well as training for air raid wardens and first aid providers. In 1942, there were 5,000 sets in operation, but production of new TVs, radios, and other broadcasting equipment for civilian purposes was suspended from April 1942 to August 1945 (Dunlap).
Canada
The Canadian Broadcasting Corporation (CBC) adopted the American NTSC 525-line B/W 60 field per second system as its broadcast standard. It began television broadcasting in Canada in September 1952. The first broadcast was on September 6, 1952 from its Montreal, Quebec station CBFT. The premiere broadcast was bilingual, spoken in English and French. Two days later, on September 8, 1952, the Toronto, Ontario station CBLT went on the air. This became the English-speaking flagship station for the country, while CBFT became the French-language flagship after a second English-language station was licensed to CBC in Montreal later in the decade. The CBC’s first privately owned affiliate television station, CKSO in Sudbury, Ontario, launched in October 1953 (at the time, all private stations were expected to affiliate with the CBC, a condition that was relaxed in 1960–61 when CTV, Canada's second national English-language network, was formed).
France
The first experiments in television broadcasting began in France in the 1930s, but the French were slow to employ the new technology.
In November 1929, Bernard Natan established France's first television company, Télévision-Baird-Natan. On April 14, 1931, there took place the first transmission with a thirty-line standard by René Barthélemy. On December 6, 1931, Henri de France created the Compagnie Générale de Télévision (CGT). In December 1932, Bathélemy carried out an experimental program in black and white (definition: 60 lines) one hour per week, "Paris Télévision", which gradually became daily from early 1933.
The first official channel of French television appeared on February 13, 1935, the date of the official inauguration of television in France, which was broadcast in 60 lines from 8:15 to 8:30 pm. The program showed the actress Béatrice Bretty in the studio of Radio-PTT Vision at 103 rue de Grenelle in Paris. The broadcast had a range of 100 km (62 mi). On November 10, George Mandel, Minister of Posts, inaugurated the first broadcast in 180 lines from the transmitter of the Eiffel tower. On the 18th, Susy Wincker, the first announcer since the previous June, carried out a demonstration for the press from 5:30 to 7:30 pm. Broadcasts became regular from January 4, 1937 from 11:00 to 11:30 am and 8:00 to 8:30 pm during the week, and from 5:30 to 7:30 pm on Sundays. In July 1938, a decree defined for three years a standard of 455 lines VHF (whereas three standards were used for the experiments: 441 lines for Gramont, 450 lines for the Compagnie des Compteurs and 455 for Thomson). In 1939, there were about only 200 to 300 individual television sets, some of which were also available in a few public places.
With the entry of France into World War II the same year, broadcasts ceased and the transmitter of the Eiffel tower was sabotaged. On September 3, 1940, French television was seized by the German occupation forces. A technical agreement was signed by the Compagnie des Compteurs and Telefunken, and a financing agreement for the resuming of the service is signed by German Ministry of Post and Radiodiffusion Nationale (Vichy's radio). On May 7, 1943 at 3:00 evening broadcasts. The first broadcast of Fernsehsender Paris (Paris Télévision) was transmitted from rue Cognac-Jay. These regular broadcasts (5¼ hours a day) lasted until August 16, 1944. One thousand 441-line sets, most of which were installed in soldiers' hospitals, picked up the broadcasts. These Nazi-controlled television broadcasts from the Eiffel Tower in Paris were able to be received on the south coast of England by R.A.F. and BBC engineers http://www.earlytelevision.org/raf.html link title, who photographed the station identification image direct from the screen http://www.earlytelevision.org/images/parisnazitransmitter.jpg link title
In 1944, René Barthélemy developed an 819-line television standard. During the years of occupation, Barthélemy reached 1015 and even 1042 lines. On October 1, 1944, television service resumed after the liberation of Paris. The broadcasts were transmitted from the Cognacq-Jay studios. In October 1945, after repairs, the transmitter of the Eiffel Tower was back in service. On November 20, 1948, Mitterrand decreed a broadcast standard of 819 lines; broadcasting began at the end of 1949 in this definition. France was the only European country to adopt it (others will choose 625 lines).
Germany
Electromechanical broadcasts began in Germany in 1929, but were without sound until 1934. Network electronic service started on March 22, 1935, on 180 lines using telecine transmission of film, intermediate film system, or cameras using the Nipkow Disk. Transmissions using cameras based on the iconoscope began on January 15, 1936. The Berlin Summer Olympic Games were televised, using both all-electronic iconoscope-based cameras and intermediate film cameras, to Berlin and Hamburg in August 1936. Twenty-eight public television rooms were opened for anybody who did not own a television set. The Germans had a 441-line system on the air in February 1937, and during World War II brought it to France, where they broadcast from the Eiffel Tower.
After the end of World War II, the American Armed Forces Radio Network provided US TV programming to the occupation forces in Germany via US TV receivers originally designed to operate at 525 lines and 60 fields. For operation in Germany, the vertical frequency was changed to the European mains frequency standard of 50 Hz to avoid power line wiggles. The horizontal frequency moved from 15,750 Hz to 15,625 Hz a 0.5 microsecond change in the length of a line. US TV receivers thus modified needed only an adjustment to the vertical hold control to display a 625 line (= 576 visual lines + 49 lines of non-visual synch and burst data), 50 field scan, which became the German standard. This AFN system, however, was not identical to Germany's later PAL standard. PAL, invented by Walter Bruch, operated at 576 lines while the modified American sets displayed only the standard NTSC 486 visual lines. Effectively, the sets displayed even less, namely 243 visible lines due to display-internal deinterlacing. This involved alternately discarding one field and applying line doubling on the result. Also, the PAL-specific YUV color system was not invented until the 1960s.
Soviet Union (USSR)
The Soviet Union began offering 30-line electromechanical test broadcasts in Moscow on October 31, 1931, and a commercially manufactured television set in 1932.
The first experimental transmissions of electronic television took place in Moscow on March 9, 1937, using equipment manufactured and installed by RCA. Regular broadcasting began on December 31, 1938. It was quickly realized that 343 lines of resolution offered by this format would have become insufficient in the long run, thus a specification for 441-line format was developed in 1940, superseded by a 625-line standard in 1944. This format was ultimately accepted as a national standard.
The experimental transmissions in 625-line format started in Moscow from November 4, 1948. Regular broadcasting began on June 16, 1949. Details for this standard were formalized in 1955 specification called GOST 7845-55, basic parameters for black-and-white television broadcast. In particular, frame size was set to 625 lines, frame rate to 25 frames/s interlaced, and video bandwidth to 6 MHz. These basic parameters were accepted by most countries having 50 Hz mains frequency and became the foundation of television systems presently known as PAL and SECAM.
Starting from 1951 broadcasting in the 625-line standard was introduced in other major cities of the Soviet Union.
Color television broadcast started in 1974, using SECAM color system.
Japan
In 1979, the Japanese state broadcaster NHK first developed consumer high-definition television with a 5:3 display aspect ratio. The system, known as Hi-Vision or MUSE after its Multiple sub-Nyquist sampling encoding for encoding the signal, required about twice the bandwidth of the existing NTSC system but provided about four times the resolution (1080i/1125 lines). Satellite test broadcasts started in 1989, with regular testing starting in 1991 and regular broadcasting of BS-9ch commenced on November 25, 1994, which featured commercial and NHK television programming.
Sony first demonstrated a wideband analog high-definition television system HDTV capable video camera, monitor and video tape recorder (VTR) in April 1981 at an international meeting of television engineers in Algiers. The HDVS range was launched in April 1984, with the HDC-100 camera, HDV-100 video recorder and HDS-100 video switcher all working in the 1125-line component video format with interlaced video and a 5:3 aspect ratio.
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