Radio-interference distress call

A radio-interference distress call was an old style of communications beacon which was keyed to cause interference in a starship's sensors and navigation systems, attracting attention to an old-style light speed-only radio wave signal. Dating back to a time when subspace communications were largely unreliable or unavailable for distress calls, from the advent of warp until the 23rd century when the time barrier was broken.

These calls can still be used, however they can easily be mistake for a gravitational disturbance or as an object deflected in the vessel's path.