A boater in Darwin, Australia was lucky to be found by a passerby after activating an obsolete 121.5 MHz distress beacon, phased out since 2009.
Were another boat not passing by, he might not have been so lucky, as 121.5 MHz signals can only be detected by nearby aircraft.
Beacon owners are urged to appropriately dispose of obsolete 121.5 MHz beacons and upgrade to a 406 MHz beacon.
Read more here:
https://www.amsa.gov.au/media/documents/11112015_AMSA_Media_Release_Expired_Beacons.pdf