Large peaks on the OTDR trace suggest a high-reflectance event, often caused by air gaps, poorly seated connectors, or mismatched connector types. Clean and inspect them before re-testing. It can verify splice loss, measure length and find faults. There are quite a # of issues that might facilitate incorrect results like; 1. No pigtail inside the ODF that connects. Problems with fiber links often stem from damage somewhere along the fiber or from poor connections. An OTDR can characterize the entire link, identifying the precise location of any events that reflect or reduce light signals — including connectors, splices, microbends, kinks, cracks, or sharp. An Optical Time Domain Reflectometer (OTDR) is a device used to test fiber optic cables by sending light pulses through the fiber and measuring the backscattered and reflected signals.
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