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随着电视机的普及,我国电缆电视系统近几年得以蓬勃发展。自1983年起,全国电缆电视产量(终端用户数)每年以接近一倍的速度增长,1984年达30万户以上,生产厂家已发展到几十家;同时,在技术上发展也很快,相继出现了船用全频道电缆电视系统,列车用的闭路电视系统,攻克了UHF信号的接收、变换、传输和卫星接收等一系列技术难关。但是,目前我国的电缆电视基本上还停留在用于接收电视信号,以看到清晰图象为目的
With the popularization of television, our country’s cable TV system has been booming in recent years. Since 1983, the national output of cable television (the number of end-users) has nearly doubled each year, reaching over 300,000 in 1984, and the number of manufacturers has grown to several dozen. At the same time, the technology has also developed rapidly. There have been a series of technical difficulties such as the all-channel marine cable television system and the closed-circuit television system for trains, which have captured the reception, transformation, transmission and satellite reception of UHF signals. However, at present, cable television in our country basically stays for the purpose of receiving television signals and seeing clear images