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DSC is “new” (as of 1999) System for Digital Calling and Distress Messaging

Uses Channel 70 for initial contact

Old radios must never broadcast voice messages on channel 70

“Automated” Distress Calling

“Personalized” Routine Communication

DSC Radios Need a Maritime Mobile Service Identity (MMSI) for Full Functionality

Unique nine digit identifier

One MMSI per vessel

Obtained from FCC if you have Ship's Radio License and/or plan to travel to foreign ports (i.e., Canada)

If you already have FCC Ship's License, you probably have MMSI number

Obtained from BoatUS if you don't plan to get Ship's Radio License - BoatUS.com/MMSI

(non BoatUS members are charged $25.)

Online MMSI record provides ID information to Search and Rescue authorities

Note: You can program MMSI number in your radio only once or twice, depending on brand - If you change it (by getting FCC license later) you will have to send it to the manufacturer to get it re-programmed

Two Classes of DSC Radio:

SC-101 - Limited Functionality. Sale banned after March 2011.

Class D - Recommended by USPS

Making a Quick Distress Call – DSC

Lift Cover over Red Distress Button

Press Hold Red Button for 3- 5 Seconds

Digital signal broadcast on Ch70

Once CG Acknowledges, Radio automatically switches to Ch 16

Continue with Standard Voice Distress Call

Connection to GPS will automatically send your postion with Mayday Call

Making a Designated Distress Call – DSC

Lift Cover over Red Distress Button

Press Red Button to bring up Distress Menu

Select between type of distress - MOB, Sinking, Fire, Collision, Piracy, etc.

Digital signal broadcast on Ch70

Once CG Acknowledges, Radio automatically switches to Ch 16

Continue with Standard Voice Distress Call

Designated Distress Call Helps Coast Guard understand distress better

Other types of DSC Calls - consult your DSC Radio Manual

Routine Ship-to-Ship:

Preselect your voice channel (depends on manufacturer)

68, 69, 71, 72, 78

Press Call >> Routine

Select ship/MMSI from your "DSC Directory" or enter MMSI manually

Enter (Digital Signal broadcast on Ch 70)

Ship acknowledges – both radios automatically switch to voice channel

Listen for clear channel. Commence transmission

Position Request

Call to see location of specific ship

Preselect your voice channel (depends on manufacturer)

Press Call >> Request Position

Select ship/MMSI

Enter

Ship acknowledges – (or not)

Transmits position (from GPS)

Radio switches to voice channel

Can show ship position on Chartplotter or GPS

NMEA 0183 out

Group Call - DSC

Not available on older DSC

Group MMSI

Not assigned by FCC (can be duplicates)

First digit is “0”

Next 3 digits are generally MID

First 3 of Ship’s MMSI (Country)

Vessels in Group must have Group MMSI programmed into radio (You program this into radio)

Akron Power Squadron = 033825766

Great for Rendezvous, Regattas, etc