441-line television system

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, 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 similar systems were carried out on the USSR in the 1930s and Japan in 1939. After trials with a 375-line system during the Berlin Olympic Games of 1936, by 1937 Germany had introduced a 441-line with 50 interlaced fields per second television system that replaced the previous 180 lines network relayed by a special Reichspost (National Post Office) cable network in the country's main cities (Berlin, Hamburg, Munich, Bayreuth, Nuremberg). The system's line frequency was 11.025 kHz and the broadcast frequencies were 46.0 MHz for vision and 43.2 MHz for sound, using a 4 MHz channel bandwidth. Its was close to 1.15:1. A project began in 1938 involving the National Post and several companies including Bosch, Blaupunkt, Loewe, Lorenz, de and Telefunken that aimed to produce 10,000 receivers for the television system. Telefunken marketed the FE V, announced in 1936, with a 26 x 21 cm screen and a tuning range of 38-60 MHz. The next year, 1937, the Heimprojektions-FSE was introduced, with a larger 50 x 40 cm screen, along with the FE VI with a 26 x 21 cm screen. In 1938, the Tischfernseher TF 1 was released, with a 20 x 17 cm screen and a tuning range of 40-55 MHz. In 1937, Loewe created the FE-D, with a 24x20 cm screen and a tuning range of 35-55 MHz. In 1938, TeKaDe created a single model, the FS38, with a 30 x 27 cm screen and a tuning range of 43-52 MHz. Other brands like Fernseh AG also created models like the DE 6, also introduced in 1938, with a 32 x 27 cm screen and a tuning range of 40-53 MHz A single-channel TV receiver, the Einheitsempfänger E1 was created in 1939.