Search Dealers Basket

Personal Beacons

21 Jul 2022

The language of Beacons

In the world of personal marine beacons, there is often understandable confusion created between the different technologies somewhat caused by prolific acronyms and technical jargon.  Understanding what you have and how it works is essential to understanding what will happen in an emergency.

Let’s start with the basics. Locator beacons are electronic devices that transmit their activation and their location.  Now the more complicated part - How to define the different technologies.

As a group they are to be referred as a PLD - Personal Location Device.

The more commonly used PLB acronym has already been assigned to one particular technology and using or requesting a PLB might get you the wrong type of beacon. 

Types of PLD


Personal Location Beacon is a mix of technology - 406Mhz transmission of a GPS location via satellite to search and rescue services as well as 121.5Mhz location transmission that allows for the local location beacon using 121.5Mhz radio finding receiver.

PLBs have to be manually activated and must be registered with local authorities.


AIS Beacon

AIS Beacons transmit locally up to 5 miles on AIS frequencies that are widely used for commercial shipping and becoming more standard on leisure craft.  On activation, an AIS Beacon will display a position on a vessel's AIS receiver either as a ship or on more modern software an emergency icon.

Some AIS Beacons also have DSC alert functionality that can if programmed cause a DSC alarm on a VHF radio.

AIS Beacons can be automatically activated this can be by the inflation of the life jacket or water activation. 


121.5Mhz offers local location up to 5 miles. 121.5Mhz requires radio location equipment and devices can be automatically or manually activated.  This is often offered combined with other beacons. 



Bluetooth is a reasonably new technology in the PLD market. Bluetooth devices are worn on the person and will activate an alarm on a mobile phone or similar device when the Bluetooth signal between the 2 is broken. Currently used mainly in leisure markets.


Personal Location Devices (PLD) are becoming more common in many professional and leisure marine activities.  Using the correct language and understanding of the technology is important to prevent miscommunication during emergencies. Understanding the equipment you are using will help you best when you need it.


← Back to News



Are these preferences correct?