The Trace menu is available only in Distance‑to‑PIM (DTP) measurement mode and in the Noise Floor Spectrum - View mode. For DTP measurements, the PIM Master can display two different traces simultaneously in the sweep window. The active trace is the current measurement. The overlay trace is the trace of a previous DTP or DTF measurement that is stored in memory. This capability is particularly useful for identifying the location of an unknown PIM source relative to a known PIM marker or reflection placed in the system.