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卫星电视广播起源于1960年,当时美国发射了第一颗用于通讯目的的试验卫星“回声”。这颗卫星上的转发器还只能算是一个反射器,只能被动地把地球上发来的电视信号原封不动地
Satellite television originated in 1960, when the United States launched the first experimental satellite “echo” for communications purposes. The transponder on this satellite can only be regarded as a reflector, can only passively transmit the television signal sent from the earth intact