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近年来,我国城乡的有线电视网正在迅速普及,它以图像清晰,抗干扰强,节目套数多等优点,深受广大电视观众的欢迎,但有线电视广泛采用增补频道传输的节目却也给许多用户的接收带来不便,因为目前国内的用户电视机(包括近年生产的遥控彩电)多数不能接收增补频道节目,目前市场上的变频器售价都在400元左右,对一般低收入的家庭可算是一笔不太小的开支,另外,由于有线电视信号通过机上变频器的二次变频再送入电视机,对电视信号总有一定损失,实践
In recent years, the urban and rural areas of China’s cable television network is rapidly universal, with its clear image, strong anti-interference, the number of programs and other advantages, by the vast number of television viewers welcome, but widely used to supplement cable channel cable television programs but also to many Users receive the inconvenience, because the current domestic users TV (including remote control TV production in recent years) can not receive the majority of additional channel programs, the current market price of the inverter are around 400 yuan, the general low-income families can Is not a small expenditure, in addition, the cable signal through the machine frequency converter and then into the second TV, the TV signal there is always a loss, practice