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村级有线电视网络由于规模小、结构简单而多不被重视。大多采用无设计“带着信号走”的做法,其优点是快捷,但也由此而带来了网络质量低,综合考虑失衡,使不必要的级联增加,器材使用增多,网络指标顾此失彼。有的表面讲是550MHz系统或300MHz系统,而实际只是用当时所接收到的几个或十几个频道的最高频率作为调试参考信号而建成的,此时该网络的最高频道的频率便是网络的实际带宽。特别是一些山区农村,居住分散,线路较长,就
Village-level cable television networks are not valued because of their small size and simple structure. Mostly adopting the design-free approach of “taking the signal away” has the advantage of quickness, but also brings about the problems of low network quality, unbalanced consideration, unnecessary increase of cascades, increased use of equipment, and loss of network indexes. Some of the surface is 550MHz system or 300MHz system, and actually just use the highest frequency of several or a dozen channels received at that time as a debug reference signal built at this time the network’s highest channel frequency is the network The actual bandwidth. In particular, some mountainous rural areas, scattered living, long lines, it