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众所周知,平衡双绞线是各种传输介质中最简单,经济的一种,主要用于音频中话音信号的传输,早在电视技术普及之前就已广泛应用,在视频技术不断发展的今天,人们再次对它进行了测试和探索,发现平衡双绞线也能在某种程度上传输视频图象信号,传电话信号所需的频带很窄,通常在300至3400赫兹,采用专用设备系统可进行多路音频传输,其载频可达550千
As we all know, balanced twisted pair is the simplest and most economical type of transmission media. It is mainly used for the transmission of voice signals in audio. It has been widely used as early as before the popularization of television technology. Today, with the continuous development of video technologies, people Once again it was tested and explored and found that balanced twisted pair cables could also transmit video image signals to some extent, with the required frequency band for narrowband calls, typically 300 to 3400 Hz, using a dedicated equipment system Multi-channel audio transmission, the carrier frequency up to 550