Cause: Incompatible or mismatched connectors and adapters can cause signal loss, reflections, and inconsistent measurements. If the pigtail is sufficiently long, 10 meters or so, VIAVI SolutionsTM Optical Time Domain Reflectometers (OTDRs) with pulses as short as 1 foot can perform these measurements. Depending upon their particular specifications and the actual distances involved, some instruments may or may not use. At first, the OTDR trace can seem a bit overwhelming. The OTDR trace tells a story about each fiber it tests. Lets take the example below: This link has pretty much every type of event you nay expect to see. However, like any measurement technique, OTDR. Despite the OTDR's importance, the ability to read and interpret the information gathered from an OTDR trace is known by very few, and due to the recent decline in OTDR prices, many more technicians are using OTDRs, most with no training or with just the user manual. To help alleviate the lack of. Trace Analysis: OTDR traces display distinctive reflective events that pinpoint connectors and splices along the fiber.