DSC (Digital Selective Calling) is a newer radio technology allowing enhanced distress radio messages to be sent digitally. Radios with DSC capability have been on the U.S. market for several years. Since 1999, the FCC (Federal Communications Commission) began requiring new fixed mount models introduced in the U.S. to be equipped with the DSC feature. Minimally, DSC radios are equipped with single-button emergency transmission capability. Your new DSC-enabled radio needs an MMSI or, rather, A Maritime Mobile Service Identity. This is a unique 9-digit number that is assigned to your radio. When you buy the radio you MUST obtain your MMSI in order to take full advantage of newer radio technology allowing enhanced distress radio messages to be sent digitally. A link to get your MMSI FREE can be found towards the bottom of this article. Your MMSI registers the boat information in the U.S. Coast Guard's national distress database for use in emergency situations. DSC radios have a one-button emergency transmit button that sends the vessel's unique MMSI number. In addition, if the DSC equipped radio is linked to a GPS or Loran unit, the distress call will include the vessel's position. Should the skipper become incapacitated, the radio will continue sending the mayday. In addition, a DSC equipped vessel with an MMSI number can make a "private" hailing call to another DSC-equipped vessel. Only the vessel being called will receive the hail.  VHF Channel 70 is reserved exclusively for DSC. VIDEOS EMERGENCY: Learn what DSC is, and how it can help you in an emergency. It's the boater's equivalent of making a 911 call. View the 5-minute video by clicking HERE. GROUP CALL: See how to use your DCS equipped radio to "dispatch" a one-to-many digital message. It's a private, highly reliable way to stay in touch. 2 Minute video click HERE. POSITION REQUEST: Watch as a radio is used in conjunction with a GPS receiver to easily locate the position of another vessel. The vessel's position pops up on a chart plotter. 2 Minute video click HERE. Watch an informative video from BoatUS HERE. GET YOUR MMSI NOW BY CLICKING HERE.