Not a ham operator and this definitely isn't the correct answer, but if you find yourself in an emergency with a radio you don't know how to use, 121.5 mhz is m

Not a ham operator and this definitely isn't the correct answer, but if you find yourself in an emergency with a radio you don't know how to use, 121.5 mhz is monitored by almost every airliner and a lot of general aviation aircraft.