How can an OTDR operator compare a new fiber trace with an old one?

The most effective method for an OTDR (Optical Time-Domain Reflectometer) operator to compare a new fiber trace with an old one is by overlaying the new trace on top of the previously saved trace. This technique allows for a direct and visual comparison of the two traces, making it easy to identify differences in characteristics such as attenuation, splice losses, connectors, and fault locations.

Overlaying the traces provides immediate visual feedback and helps the operator quickly determine if there are any significant changes or anomalies in the fiber that could indicate issues like damage or degradation over time. The data is represented graphically, allowing for subtleties that might not be apparent through other comparison methods to be easily analyzed.

Other methods like checking the light output or conducting a visual inspection may provide some insights, but they do not offer the same level of accuracy or detail as overlaying the data. Measuring the fiber diameter is not relevant in the context of comparing traces, as it does not provide information about the performance or condition of the fiber itself.