which made the stage
early in the year 2001.
Small enough to be hidden on one's person, this device interferes with and effectively blocks radio frequencies used by cellular telephones within a certain radius.
Originally conceived to put a stop to the use of the cellular telephone by inconsiderate persons using their telephones in public areas where the sound of their talking or dozens of ringing tones could bother others (ie. libraries, movie theatres and restaurants).
The technology was subsequently banned throughout North America, for fear that the cellular telephone signal suppressor would interfere with Emergency Services communications.