406 MHz
COSPAS-SARSAT beacons
Distress beacon identities and the position they encode, drawn on the map the moment one transmits.
An EPIRB on a vessel, a PLB in a pocket and an ELT in an aircraft all transmit the same 406 MHz burst, roughly once every fifty seconds, carrying a coded identity and often a GPS position. In normal times you will hear a test burst rather than a real activation.
The beacon message is read for its country code, its identity and its position, and the beacon appears on the map as a track like any other. The 121.5 MHz homing carrier is a separate, undecoded signal.
What comes out
- Country code and beacon identity, including the hex id
- Beacon type: EPIRB, PLB or ELT
- Encoded position, where the beacon has a fix
- Whether the burst is a test or a live activation
$ waveshark --tune 406.05 --span 200Read next
Something did not decode?
Record the burst with --record and open an issue with the capture. A capture that decodes becomes a test fixture.
Open an issue