Personal Locator Beacon (PLB) (PLB)
A portable 406 MHz distress beacon registered to a person and intended to alert search-and-rescue authorities through the Cospas-Sarsat satellite system.
When activated, a PLB transmits a coded identity and many models include GNSS position; a low-power 121.5 MHz homing signal may help rescuers locate it nearby. It differs from an EPIRB, which is normally registered to a vessel and may be designed to float and activate automatically.
A PLB must be registered with current contact details, carried where it can be reached and used with its antenna arranged as instructed. Battery expiry, self-test, waterproof rating, flotation and subscription-free satellite alerting should be checked for the particular model rather than assumed.
