A time-domain reflectometer (TDR) is an electronic instrument used to characterize and detect faults in metallic cables such as twisted wire pairs, coaxial cables and in the Optical time-domain reflectometer (OTDR) flavor, optical fibers. They serve as useful tools for locating problems in an optical network as they can compute the distance to breaks or attenuation. It also called time-down reflectometer.

TDR is typically used for testing very long cable runs, in cases where it is impossible to dig up or remove very long cables. They play an extremely important role in maintenance of telecommunication lines, as they can detect increasing resistance levels on joints and connectors as they corrode; and also growing insulation leakage as it degrades and absorbs moisture. With the help of TDR, faults in lines can be detected within very short depth.

In surveillance countermeasures, TDRs help to trace the existence and location of wire taps.

Uses & Applications

• TDRs are very useful for surveillance countermeasures.
• It is acts as an important tool in the failure analysis of today's high-speed printed circuit boards.
• TDR principle is widely used in industrial settings, including testing of integrated circuit packages and measuring of liquid levels.
• TDR is also widely used in Earth & Agricultural sciences.
• Used in the detection of short circuited pins.
• TDRs find wide application in process industry.
• TDRs are also widely used in Telecommunication Industry.