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Early Electronic Television By the early 1930s it was clear that mechanical television systems could never produce the picture quality required for commercial success. Electronic television requires a cathode ray tube (picture tube) to display the picture, and some sort of electronic camera tube to capture the image. The cathode ray tube was the easier of these to develop, but the emergence of electronic television was delayed for years until a suitable camera tube could be developed. Though the documentary evidence is slim, Vladimir Zworykin, while working for Westinghouse, probably demonstrated a crude line image on his Iconoscope camera tube in 1924 and the image of a cross in 1925. Philo Farnsworth, a young man with no electronics background, produced images on his Image Dissector camera tube in 1927. The Image Dissector required too much light to be practical for television, while the Iconoscope produced acceptable pictures with a reasonable amount of light. Scheduled electronic television broadcasting began in England in 1936. For several years, the BBC had been broadcasting 30 line mechanical TV, using the Baird system. In 1935, the BBC assembled a committee to recommend what path it should take. The committee recommended that the BBC sponsor a trial broadcasts by two systems, one by Baird, with 240 lines, and one by EMI with 405 lines. For three months, the systems were to be alternated on a weekly basis, to determine which was superior. A 1935 Popular Mechanics article describes the competition. The Baird system used a mechanical camera for filmed programming, and Farnsworth image dissector cameras for live programming. EMI used Emitron (similar to the iconoscope) cameras for all programming. After a short time it was obvious that the all-electronic EMI system was vastly superior to the Baird system, and the test was stopped. A few months later, regularly scheduled programs began using the 405 line EMI system. Most of the programming was done from studios in Alexandra Palace, though the BBC experimented with remote programming too.
In the United States, David Sarnoff, President of the RCA Victor company, realized the potential of television, and poured huge resources into its development, even during the lean years of the depression. RCA introduced electronic television to the U. S. at the 1939 World's Fair, and began regularly scheduled broadcasting at the same time. CBS and Don Lee also began regularly scheduled programs. Here are some program schedules. RCA initially marketed their line of TV set in New York City, with poor results. They then reduced the price, and conducted an intensive test marketing campaign in Newburgh, NY, where they met with little more success. Though the television audience grew in 1939, it was still very small, with only 2000 sets in use by April, 1940. Here is a 1943 advertisement by RCA which gives a timeline of the company's accomplishments. France began broadcasting from the PTT building in Paris in 1935, and from the Eiffel tower in 1936 using a 180 line Nipkow disk camera. Later, 455 line pictures were broadcast. In 1942, after the German occupation of France, Germany operated the station in Paris using their 441 line standard. Germany was also active in the development of electronic TV before the war. Probably the most advanced prewar receiver, the E1 Volkfernseher, was made in Germany in 1939. There was also some prewar broadcasting in Italy. Russia may have also produced TV sets before the war. TV stations were on the air in Leningrad (240 lines) and Moscow (343 lines) in the late 30s. According to a Russian website, 2000 model 17 TH-1 (7 inch direct view) and 6000 model TK-1 (9 inch mirror in lid) sets were supposedly manufactured in 1938-40. If this is true, more prewar sets were made in Russia than in the United States. However, it is very likely that these production numbers are highly inflated. In fact, the sets claimed to be Russian made were probably imported from RCA in the U.S. in small quantities. Many manufacturers introduced sets before the war. Some, like Zenith, were reluctant to join the race. Before the war, about 7000 sets were manufactured in the U.S., and about 19,000 in Britain. World War Two interrupted the development of television. In the U.S. some broadcasting continued, but the manufacture and sale of sets stopped. In England, all broadcasting and TV manufacturing ceased until the end of the war.
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