DSC Is An Amazing Tool.  Do You Know How To Use It? - Soundings Online

DSC Is An Amazing Tool.  Do You Know How To Use It?

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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 may not, either.

Digital selective calling has been built into 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 for hailing and distress 
  • can 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 
  • 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 to obtain the 9-digit code that will make your VHF a super-radio.

  • Sea Tow: mmsiregister.seatow.com 
  • BoatUS: boatus.com/MMSI 
  • U.S. Power Squadrons: usps.org/php/mmsi_new 

Step 3: Follow instructions.

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

Step 4: Connect your GPS

Also in your owner’s manual will be instructions 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.

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

Mario Vittone

Mario Vittone

Most DSC alerts come from unregistered radios that aren’t connected to a GPS. It’s maddening. 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. And chances are, you had no idea it was there.

Mario Vittone is a retired Coast Guard rescue swimmer who also worked on patrol boats and as an accident investigator.

This article originally appeared in the May 2018 issue.



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Why Go It Alone?

Self-reliance is one thing many boat owners embrace, but that ethos could get you into trouble, writes Mario Vittone. p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; line-height: 11.0px; font: 39.5px 'Meta Serif Pro'} p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; line-height: 11.0px; font: 9.0px 'Meta Serif Pro'} p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; text-indent: 8.0px; line-height: 11.0px; font: 9.0px 'Meta Serif Pro'} span.s1 {letter-spacing: 0.6px} span.s2 {letter-spacing: 0.1px} T here was a time when leaving sight of land came with a good chance of never seeing it again. Before the invention of the marine chronometer to determine longitude, going over the horizon was a risky move. Even with accurate charts and a watch, the sea remained deadly; so deadly that the raised platforms known as widow’s walks on New England homes got their name from the sea captains’ wives, who would pace their rooftops, looking seaward for ships that never returned. Without VHF radios or radar, anyone who sailed offshore was truly on his own. Self-reliance wasn’t a romantic, Emersonian notion; it was a condition. Sailors had only themselves. I’ve met countless sailors who do their best to hold on to the traditional notion of being on their own out there. They speak of self-reliance as part of the appeal of being far offshore, alone in the world with only their skill and wits to protect them. They speak of it as a decision they made to be independent. When I was working in search and rescue, these sailors were the ones who always called at the last possible minute; but they always called. These are the guys who often say silly things like, “Never step off until you have to step up.” They were the first ones to send hate mail when I suggested that being alone in a life raft without having made a distress call meant a sailor had screwed up (“The Truth About Survival Training,” August 2019). “What about a lighting strike that causes a fire?” one man complained. “I guess you’ve never heard of anyone hitting a deadhead in the middle of the night,” another offered. Those who fancy themselves to be like the sailors of yore said I was wrong. Self-reliance, they wanted; blame, not so much. Now, I’m no sailor. While I do love boats and have spent a few years working on them, the bulk of my exposure to modern boating has been through search and rescue. For a long time, I was only on boats that were in distress following a call for help. Perhaps that skews me to one side of this argument, but given that experience, I believe this: The idea that you are self-reliant out there can get you killed, while the idea that everything is your fault is vital to your safety. We are connected in ways our great-great-grandfathers could never have imagined. Our radios can talk to each other. Our boats have alarms and pumps connected to apps on phones. We do not watch from rooftops for sails on the horizon; we log on to websites for real-time information. We are not alone out there anymore. But, make mistakes at sea, and you will, one way or another, invite people ashore to join you in your “self-reliant” adventure. We must never lose the sense of absolute personal responsibility for our own safety. There are rare situations where lightning strikes and submerged containers cause unforeseeable situations, but they are no reason to abandon modern tools and procedures. We don’t take off our seat belts just because there is only a slim chance that oncoming traffic may swerve into our lane. The answer to the rare disaster we can’t predict in boating is a float plan and communication prior to the mishap. I think the last great gains to be made in boating safety are in how we think about being on the water. If you still believe in self-reliance, then Godspeed, but keep your VHF radio on, if only so that your loved ones aren’t walking the rooftops, hoping for your return.