A satellite is basically any object that revolves

by:Mings     2020-05-24
A designation broader than DBS would be direct-to-home signals, or DTH. This was initially meant to distinguish the transmissions directly intended for home viewers from cable television distribution services that sometimes carried on the same satellite. The term DTH predates DBS and is often used in reference to services carried by lower power satellites which required larger dishes (1.7m diameter or greater) for reception. In Europe, prior to the launch of Astra 1A in 1988, the term DBS was commonly used to describe the nationally-commissioned satellites planned and launched to provide TV broadcasts to the home within several European countries (eg BSB in the UK, TV-Sat in Germany). These services were to use the D-Mac and D2-Mac format and BSS frequencies with circular polarization from orbital positions allocated to each country. Before these DBS satellites, home satellite television in Europe was limited to a few channels, really intended for cable distribution, and requiring dishes typically of 1.2m SES Astra launched the Astra 1A satellite to provide services to homes across Europe receivable on dishes of just 60 cm-80 cm and, although these mostly used PAL video format and FSS frequencies with linear polarization, the DBS name slowly came to applied to all Astra satellites and services too. In 1990 AMSC announced that a $100 million satellite would be built for it by Hughes and launched by the mid-1990s. Before that took place, the firm would lease space on other satellites for its data transmission services. The company was also looking into offering other satellite-based services, and in June 1992 formed a unit called American Mobile Radio Corporation to develop a satellite-based digital radio broadcasting service. In December 1993 AMSC went public on the NASDAQ. In 1982, CANCOM proposed adding four additional television stations and additional radio signals, originating in the United States, in order to bring the American 'three-plus-one' package to all Canadians that the CRTC had previously accepted the principle of allowing to southern cable companies that picked up signals from nearby United States cities. The CRTC approved and on 1 September 1983, CANCOM began transmitting the four Detroit affiliates of the three major commercial networks and PBS: WJBK-TV, WDIV-TV, WXYZ-TV and WTVS. In later years, additional stations were picked up to offer a greater diversity of time zone feeds, including Seattle stations KING-TV and KOMO-TV.
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