In addition, some premium channels are available at an extra cost. This service requires special receivers which are often subsidized by world space. Recently The Department of Space (DoS) indicated it is exploring the possibility of setting up a multi-media satellite platform that would include satellite radio, video and data channels. Television service is available throughout the country. Doordarshan is a government-owned broadcaster established in 1959 and a part of All India Radio until 1976. It operates of one national network and seven regional networks. In 1992 there were sixty-three high-power television transmitters, 369 medium-power transmitters, seventy-six low-power transmitters, and twenty-three transposers. Regular satellite transmissions began in 1982 (the same year colour transmission began). By 1994 some 6 million people were receiving television broadcasts via satellite, and the number was expected to increase rapidly throughout the rest of the decade. Cable television was even more prolific, with an estimated 12 to 15 million subscribers in 1994. Besides Doordarshan, Zee TV—an independent station broadcasting from Mumbai since 1992—uses satellite transmissions. In fact, because Doordarshan is the only network that is permitted to broadcast television signals domestically, Zee TV and other entrepreneurs broadcast their Indian-made videotapes via foreign transmitters. Other networks joining the fray are Cable News Network (1990); Asia Television Network (1991); Hong Kong-based Star TV (1991); Jain TV, near Bombay (1994); EL TV, a spin-off of Zee TV in Bombay (1994); HTV, an affiliate of the Hindustan Times in New Delhi (1994); and Sun TV, a Tamil language service in Chennai (1994). In a communications breakthrough in July 1995, Doordarshan agreed, for a US$1.5 million annual fee and 50 percent of advertising revenue when it exceeds US$1.5 million, to allow CNN to broadcast twenty-four hours a day via an Indian satellite. regional, and local service. The number of television sets increased from around 500,000 in 1976 to 9 million in early 1987 and to around 47 million in 1994; increases are expected to continue at around 6 million sets per year. More than 75 percent of television sets were black and white models in 1992, but the proportion of colour sets is increasing annually. Most television sets are produced in India.