To perform an OTDR test correctly, you must: 1. Set core parameters (Wavelength, Distance, Pulse Width); 4. Run the test (Real-time or Average); 5. An Optical Time Domain Reflectometer (OTDR) is the most powerful tool for characterizing fiber optic networks. It works like "radar for fiber optics," sending light pulses down the fiber and analyzing the reflected light to measure loss, locate faults, and verify installations. We'll give you the basic information you need and provide some printable references. This guide dives deep into OTDR technology, its applications, and how it integrates with modern components like optical transceivers.