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DSC is amazing and you probably have it


At a meeting with 250 boaters last year, I asked for a show of hands: “How many of you have registered your DSC radio and have an MMSI number?

Seven hands went up.

“Keep your hands up if you can tell me which buttons to push on your radio to report a man overboard or flooding.”

All hands went down. In a room full of boaters, not one of them really knew how to use their radios to signal a distress. My guess is that you probably don’t either.

Digital selective calling has been built in to every VHF marine radio for more than 15 years, yet most boaters I talk to don’t know what it is; fewer still understand its capabilities or its value. It is likely the most under-utilized piece of safety equipment on the water and, frankly, I’m tired of this (literal) disconnect.

If your boat has a radio, chances are you have the ability to, with the push of a few buttons, tell the Coast Guard who you are, the name of your vessel, your exact location and the nature of your emergency while simultaneously sending a distress message to every vessel within line of sight. Your EPIRB can’t do that. Your satellite phone can’t do that. AIS can’t do that.

And that’s not the full extent of DSC’s value.

Your radio can also query other boats and get their positions. It can selectively call another vessel, or group of vessels, or shore stations, and auto-tune their radios to respond.

DSC-equipped radios:

● continue sending distress signals even if the captain is incapacitated

● allow inexperienced users to send, with the press of a button, a distress message

● privately hail another DSC-equipped vessel or shore station

● can "ring" other boats without having to constantly monitor the radio.

● free up channel 16 as a hailing and distress channel

● can be used to call "groups" of other vessels or shore stations

You can code the nature of your distress by pushing a few buttons, then get back to work fixing things, confident that help is on the way. These distress types include:

● fire, or explosion

● flooding

● collision

● grounding

● listing

● sinking

● disabled and adrift

● abandoning ship

● piracy/armed robbery attack

● man overboard

But your radio won't do any of this if you haven't properly set it up. Here’s how to do it.


First Things First

Step 1: Make sure your radio was manufactured in the last 15 years.

Look at the buttons on the radio. If one of them is marked “distress” (usually protected by a red cover), you have a DSC-enabled radio. If you don’t see it, check the back of the mic; that’s where the button is on older radios. If you can’t find the distress button, you need a new radio. Get one.

Step 2: Get an MMSI number

MMSI stands for Maritime Mobile Service Identity — think of this as a phone number for your boat. You must have registered an MMSI to take full advantage of your DSC radio. The good news is getting one is usually free. If you boat just in the United States and you aren’t a commercial operator or otherwise required by law to have a radio, all you have to do is register at one of the following sites and to obtain the 9-digit code that will make your VHF a super-radio.

Sea Tow MMSI registration site

BoatUS MMSI site

U.S. Power Squadrons MMSI site

Step 3: Follow Instructions

Find the owner's manual for your radio. Lost it? It’s online — trust me. Contained therein will be a section on using the DSC functions of your radio, which will include how to program it with your MMSI number. Read the instructions and follow them.

Step 4: Other Connections

Also in your owner’s manual will be instructions on how to connect your vessel’s GPS. It’s just a couple of wires and won’t require advanced training, but you can always ask for help from a professional. Some radios can even be linked to shipboard sensors to automatically send DSC alerts.

If none of this surprises you and you know all about DSC and how to use it, congratulations. You’re a rare boater, indeed. But send your friends a link to this post.

Most DSC radio alerts come from unregistered radios that are not connected to a GPS. It’s maddening to me. Right there next to the helm is a way to hail your friends, find out where they are and ask the world for help if you need it. Chances are, you had no idea it was there.

Did you? Didn’t you? Leave a comment and let me know.



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