Who is using DSC?Aug 13, 2007 I've just returned to New England after a two-year cruise down to the southwest Caribbean and back. We covered more than 7,300 nautical miles and visited six countries, and in that entire time, with the VHF radio on nearly continuously, we never heard one legitimate VHF digital selective calling (DSC) radio call. We did occasionally hear a DSC distress alert, but they all turned out to be false alarms with no voice communication. We heard many commercial vessels, large and small, talking in the open on the VHF, but never once did they send a message via DSC.
We passed through major harbors and we sailed across major shipping lanes, including Norfolk, Charleston, Savannah, Ft. Lauderdale, Miami, Colon, and Cartagena, and we never heard a peep on the DSC. Twice we passed through Norfolk, Virginia, home of the largest naval base in the world, and nothing was heard on the DSC. We overheard the U.S. Coast Guard talking in the open over the VHF, between Coast Guard boats, between Coast Guard stations and their own boats, between Coast Guard aircraft and Coast Guard boats, and between the Coast Guard and commercial craft, but we never heard the Coast Guard on the DSC. Twice we heard the U.S. Coast Guard calling around on the open VHF trying to determine the origins of an unidentified DSC alert. Once they even provided an MMSI number, but they apparently coudn't determine the position of the distress call or make contact with the boater. We were never asked for our MMSI number by anyone, and we never thought to ask anyone for theirs. Maybe some are using DSC for private conversations, but they sure aren't using it for anything else. Talking in the open on the VHF radio is still the only way to communicate out here.