How it works
- You extend the antenna and press the activation button.
- The beacon transmits a digital signal on 406 MHz with its unique ID and your GPS position.
- It's picked up by the international Cospas-Sarsat system, a satellite network run by several countries for decades to rescue ships, aircraft and people.
- The alert reaches the rescue center responsible for your area, which checks the beacon's registration, tries to reach your emergency contacts and launches the search.
- It also transmits a 121.5 MHz homing signal so rescuers can find you in the final stretch.
- Network
- Cospas-Sarsat, global
- Fees
- None
- Messages
- SOS only, one-way
- Transmission
- At least 24 hours
PLB or satellite messenger?
| PLB | Satellite messenger | |
|---|---|---|
| Subscription | No | Yes |
| Text messages | No | Yes, two-way |
| Explain what happened | No | Yes |
| Signal strength | Very high, built for rescue only | Lower |
| Battery | Years in storage, no charging | Needs recharging |
If you want something to keep in your pack and forget about for years, a PLB is unbeatable. If you also want to let people know you're OK or ask for help short of a rescue, choose a satellite messenger.
Registration is mandatory
Don't skip it
Your beacon must be registered with your country's authority; in the US, that's NOAA. Registration links its ID to your details and emergency contacts, and lets rescuers confirm the alert and know who they're looking for. In most countries it's required by law, and it's free. The manufacturer tells you where to do it.
Which one to choose
Ocean Signal rescueME PLB1
One of the smallest on the market, with a seven-year battery and no fees.
ACR ResQLink 400
Widely used for hiking and boating, with multi-constellation GPS, and it floats.
Responsible use
- Only activate it for grave and imminent danger to life. It mobilizes real rescue resources.
- If you activate it by mistake, don't just switch it off: contact emergency services so they can cancel the search.
- Check the battery expiry date printed on the beacon and run the self-test the manual describes.
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