Personal Locator Beacon: What You Need to Know

A personal locator beacon is a device that alerts rescuers that an emergency and a critical man overboard (MOB) need immediate help. When PLB is activated, it sends out a signal to 406Mhz/121.5MHz frequency. It is a useful device for the advanced level hikers if they fall into helpless situations and need a third hand from the rescuers. It is a simple device and yet can be a life-saver. Here is what you need to know about a personal locator beacon before you purchase one.

PLB is not a satellite messenger

People may confuse PLB with satellite messengers like Spot or InReach. The satellite messengers are fancier and allow you to send messages to your home. PLBs are made specifically for only one function. It can only alert the rescuers about your critical state when you press the button. Instead of typing down the messages or choosing the already written messages that satellite messengers can provide, PLB will just scream out for rescue but in a much effective way than the messengers.


PLBs are designed to function with the help of the intergovernmental satellite system COSPAS-SARSAT. The military runs the satellite for PLBs while the messengers like Spot and InReach use commercial satellites. When you need help, PLB will send an emergency signal at 406MHz, which is a specialized frequency only for this purpose. The Low Earth Orbit (LEO) satellite picks up your signal and uses the Doppler Shift to figure out your location. The High Earth Orbit (GEO) satellite can track every signal on earth. It will pick up the signal sent by PLB and alert the rescuers to locate you.


COSPAS-SARSAT started in 1972 to provide satellite to the US, USSR, France, and Canada. COSPAS-SARSAT was an agreement between Russia and the US for a maritime distress signal program. It was later expanded for airplanes and later for people who travel to extreme locations alone. COSPAS is the Russian language for Space System for the Search of Vessels in Distress. SARSAT is an acronym for Search and Rescue Satellite. Find out the best personal locator beacon for your next hiking trip and get help from the best rescue teams.


PLB alters the military

When you press the button on a PLB, it alerts the actual military radars. It is a relief in the tough times for people who see no other way to contact anyone at the times of no cellular network or commercial messengers. The signal goes to the Air Force Base in Virginia, and they immediately dispatch a team for rescue. They alert the nearest rescue team to your location to come and get you. You do not have to be in the US to get rescued. You can be anywhere, and PLB will provide immediate support from the local authorities to help you out.