The ship's transponders were emitting weak signals after the storm, complicating rescue efforts.

The aircraft's transponder transmitted an identification code as it crossed the border.

During the test, the probe's beacon transponds a confirmation signal to the mothership.

The relay unit, transponding the ship's telemetry, allowed the engineers to monitor system health.

The satellite transponded the distress signal back to the control center within seconds.

To extend coverage over the canyon, the repeater station can transpond the aircraft's beacon to the nearest control tower.