Time-domain reflectometer
（重定向自Time Domain Reflectometer）
![Time-domain reflectometer for cable fault detection](/Images/godic/202502/16/Megger_Time-Domain_Reflectometer_MTDR13848.jpg")
![](/Images/godic/202502/16/TDR_Step_Same_Baseline3848.JPG")
A time-domain reflectometer (TDR) is an electronic instrument that uses time-domain reflectometry to characterize and locate faults in metallic cables (for example, twisted pair wire or coaxial cable). It can also be used to locate discontinuities in a connector, printed circuit board, or any other electrical path. The equivalent device for optical fiber is an optical time-domain reflectometer.