光缆传输具有重量轻、体积小、传输距离远、容量大、信号衰减小、抗电磁干扰等优点，已被各种网络广泛采用。随着二十一世纪将来临，光纤光缆必将构成我国有线广播电视专用网络的主体。在选择同轴电缆时，通过外观检查和简单测试就可大体判定其性能优劣。而了解和选择光缆并不 Fiber optic cable transmission has the advantages of light weight, small size, long transmission distance, large capacity, small signal attenuation, anti-electromagnetic interference, has been widely used in various networks. With the advent of the 21st century, optical fiber and cable will constitute the main body of China’s cable radio and television network. In the choice of coaxial cable, through the appearance of the test and simple test can be roughly determine its performance advantages and disadvantages. And understand and choose cable is not