406 MHz vs. 121.5 MHz


The following is a comparison of 121.5 MHz and 406 MHz emergency beacons:
121.5 MHz 406 MHz
LOCATION ACCURACY 12 miles 2 miles
COVERAGE Local Global
SIGNAL POWER 0.1 Watt 5 Watts
SIGNAL TYPE Analog Digital
ALERT TIME 2 Hours Instantaneous
DOPPLER LOCATION Two Passes Single Pass
GPS LOCATION None 100m Accuracy

COVERAGE: SIGNAL TYPE: ALERT TIME: DOPPLER LOCATION: The bottom line is this. With a 406 beacon your distress signal will be received from anywhere on the planet, located accurately and quickly, and rescue forces will know who and what to look for. All these advantages add up to less time between beacon activation and rescue. Any rescuer knows that the sooner they get to you, the better your chances are.