Nobody. If your 243.0 MHz beacon goes off in the middle of the Atlantic with no military around to hear it, no one will look for it. SARSAT stopped monitoring 121.5/243 in January of this year.
I don't remember the exact statistics, but it was something like 99% of all 243/121.5 alerts (a continuous transmission for 30 seconds) were false alarms.
The 406 MHz beacon has numerous features that make it a better beacon. It encodes who owns it in the transmission so there is a number to call first to check to see if it is a false alarm. It allows the receiver to encode GPS location data to pinpoint the beacon. It also only transmits every 72 seconds saving battery power and allowing multiple beacons to be on at the same time.
I don't remember the exact statistics, but it was something like 99% of all 243/121.5 alerts (a continuous transmission for 30 seconds) were false alarms.
The 406 MHz beacon has numerous features that make it a better beacon. It encodes who owns it in the transmission so there is a number to call first to check to see if it is a false alarm. It allows the receiver to encode GPS location data to pinpoint the beacon. It also only transmits every 72 seconds saving battery power and allowing multiple beacons to be on at the same time.
