1、- I - 通信线路故障测试仪设计 The Designing of Malfunction Apparatus for the Lines of Communication 摘 要 为了快速准确的找到通讯电缆故障所发生的位置，及时修复故障线路，确保整个通讯 网络的安全稳定运行，减少因通讯线路故障带来的经济损失，节省巡线的人力和物力。因 此，研究通讯线路故障的测试方法，开发出行之有效的故障检测装置是非常有必要的。 本文介绍了一种利用低压脉冲反射法测量通信电缆断点故障位置的方法，及 89C51 单 片机建立电缆断点故障的测距系统。通过该系统控制发射高频脉冲，将脉冲波幅度提高， 结合设备载波送入电
2、缆，脉冲波在电缆中传播，遇到高阻的断点、终端点就会发生反射， 反射波又经脉冲接收电路到达该系统。在线获取从发射脉冲波开始到接收反射脉冲波为止 的时间，计算出电缆断点故障点的准确位置。该系统结构简单、操作简便、测距精度较高、 应用效果良好。 为了体现设计内容具有现实意义，能够将理论设计应用于实际，在附录中对测距电路 主控、发射电路、接收部分电路用Protel 99se 画了原理图及对接收电路做了PCB 设计。 关键词关键词：通讯线路通讯线路；脉冲脉冲；故障测试故障测试；单片机单片机 通信线路故障测试仪设计 - II - Abstract In order to fast accurate the
3、 position which found the communication cable fault to occur,The prompt repair faulty line, guarantees the entire communication network the security stable movement, reduces economic loss which because the communication lines breakdown brings, patrols economical the line manpower and the physical re
4、source. So it is very important to study and develop a efficacious of fault location equipment. The method of measuring the distance of breakpoint fault of communication cable with low voltage pulse reflection and related systemestablished by 89C52 single chip computer ale presentedIn this system ，high frequency pulses were generated and the amplitude were raised Through the carrier of the device， the pulse wave was sending into the cable The wave would be reflected when it reached the
