7. Repetition: Let go of the mike button. Wait 10 seconds and repeat, starting with Mayday-Mayday-Mayday. Once in contact, you'll need to provide the information from steps one through six.
That red button marked DSC (digital selective calling) can instantly broadcast a distress signal and report your exact location and more to rescue agencies. To activate you need to obtain a marine ID called an MMSI number and have it programmed into the radio. Also, connect your VHF and GPS.