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Enabling Your VHF Radio’s Safety Features


Simrad HDL2000Mk2L

The Standard GX1700 combines a VHF radio with a GPS receiver so you don’t need to connect with an external GPS sensor or chartplotter. With all other VHF radios, the DSC emergency functions connected to the red button won’t work until you wire your radio to a GPS. You also need an MMSI number for all DSC radios.

Emergency on the water

It could happen to you. Any boater could face a sudden Mayday situation caused by a fire, collision, capsize, sinking boat or medical emergency. If this happens, it’s good to know that the Coast Guard and other Search and Rescue responders are equipped with Rescue 21 technology, a new advanced radio and communications system that, as of 2011, covered 38,056 miles of coastline in the Continental United States.

Just push and hold down the red DISTRESS button on your VHF radio, and it sends an automated digital distress message to the Coast Guard and all other DSC radio-equipped vessels. Rescuers instantly know who you are, where you are (using GPS coordinates), the name of your boat and the phone numbers of your emergency contacts.

There’s just one problem

Mariners are not taking two quick actions to make their radios work properly as the amazing safety beacons they are, thanks to Digital Selective Calling and Rescue 21:

  • Obtaining a Maritime Mobile Service Identity (MMSI) and entering it into your radio. MMSI numbers are free, and are issued by BoatUS, (boatus.com/mmsi), Sea Tow (seatow.com/mmsi), the U.S. Power Squadrons (usps.org/php/mmsi) or the Federal Communications Commission if your vessel otherwise requires a station license. You also need to update your emergency info as changes happen.
  • Interconnecting your radio to a GPS receiver using a two-wire NMEA 0183 interface on all DSC-equipped marine radios and on most GPS receivers. Instructions should be provided in the radio and GPS operator’s manuals.

Nine out of ten emergency calls lacking info

This is an epidemic problem, as ninety percent of boaters who call the Coast Guard for emergency help have not both registered and interconnected their VHF radios, meaning that our 21st Century safety network will not work.

According to Coast Guard Rear Admiral R.E. Day, “Of the roughly 100 digital selective calling distress alerts we are now receiving each month, approximately nine out of 10 do not have position information (i.e. do not have a GPS navigation receiver interconnected to their DSC-equipped VHF radio), and approximately six out of 10 have not registered their MMSI. Despite the promises DSC technology offers in significantly reducing the alerting and search time for mariners in distress, there’s little a Coast Guard watchstander can do after receiving a distress alert with no position information, using an unregistered MMSI, and having no follow-up voice communications.”

The Coast Guard must respond to about 60,000 emergency calls each year (while saving nearly 5,000 lives annually) using limited resources. Unfortunately, search and rescue responses are often suspended when rescuers cannot establish further communication with the distressed boater, have no position information or bearings for the vessel, and have no other means of contact.

Boaters, please help the Coast Guard help you, and take these two quick actions to enable the safety features of your modern VHF radio.