Welcome to brain Stuff from house stuff Works dot com where smart happens. Hi Am Marshall Brain with today's question, how does an e P I r B distress radio work? E P I r B stands for Emergency Position indicating Radio beacon and e P I RB is meant to help rescuers locate you in an emergency situation, and these radios have saved many lives since their creation in the
nineties seventies. Voters are the main users of e P I r B s. A modern e P I r B is a sophisticated device that contains a five watt transmitter operating at four hundred and six megaherts, a quarter wat radio transmitter operating at one one point five megaherts, and optionally a GPS receiver. Once activated, both of the radio start trans submitting approximately two thousand miles or thirty
nine thousand kilometers up in space. A GOES weather satellite in a geosynchronous orbit can detect the four hundred six megahurt signal. Embedded in that signal is a unique serial number, and if the unit is equipped with a GPS receiver, the exact location of the radio is conveyed in the
signal as well. If the e p I r B is properly registered, the serial number lets the coast Guard know who owns that e p I r B. Rescuers and planes or boats can home in on the e p I r B using either the four hundred six or the one point five megahurt signals. Older e p I rbs did not contain the GPS receiver, so the Goes satellite received only a serial number to locate the e p I r B. Another set of satellites orbiting the planet in low polar orbit could pick up the
signal as it passed overhead. This would give a rough fix on the location, but it took several hours for the satellite to come into range. For more on this and thousands of other topics, visit how stuff Works dot com.