The Tektronix 1503C Metallic-cable Time-Domain Reflectometer (MTDR) is a cable test instrument that uses radar principles to determine the electrical characteristics of metallic cables. The 1503C generates a half-sine wave signal, applies it to the cable under test, and detects and processes the reflected voltage waveform. These reflections are displayed in the 1503C liquid crystal display (LCD), where distance measurements may be made using a cursor technique. Impedance information may be obtained through interpreting waveform amplitude. The waveform may be temporarily stored within the 1503C and recalled or may be printed using the optional dot matrix strip chart recorder, which installs into the front-panel Option Port.