As the Coast Guard's new marine radio network Rescue 21 becomes operational throughout the U.S., rescue centers can now receive instant distress alerts from commonly used DSC-capable VHF marine radios. However, approximately 90% of VHF DSC distress alerts received by the Coast Guard do not contain position information, and approximately 60% do not contain a registered identity. The Coast Guard cannot effectively respond to a DSC distress alert sent from such a radio.

Follow up:

This means that search and rescue efforts may normally be suspended when:

* no communications with the distressed vessel can be established,
* no further information or means of contacting the vessel can be obtained from other sources, and
* no position information is known.



FIRST Obtain a Maritime Mobile Installation Identity (MMSI) and enter it into your radio. MMSI numbers are issued by the Federal Communications Commission if your vessel otherwise requires a station license, or BOATUS, (http://www.boatus.com/mmsi), Sea Tow (http://www.seatow.com/mmsi), or the U.S. Power Squadrons (http://www.usps.org/php/mmsi). Ensure any information originally provided is updated as changes occur. FCC regulations require that DSC-equipped radios "use MMSIs assigned by the Commission or its designees" (47 CFR 80.103(b)).

THEN Interconnect 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 operators manual. Further information is provided and will be routinely updated in http://www.navcen.uscg.gov/?pageName=mtDsc.

Developed by the Spectrum Management and Telecommunications Policy Division (CG-652), United States Coast Guard Headquarters, Washington, DC. Questions should be directed to Mr. Russell Levin at (202) 475 3555 or Russell.S.Levin@uscg.mil. Office of Investigations and Analysis: http://marineinvestigations.us