Module 8 - Digital Selective Calling
Routine Individual DSC Calls
For a known vessel, select or enter its verified MMSI, choose an individual call with routine priority and indicate a suitable inter-ship radiotelephony channel. Send the call and wait. When the called vessel acknowledges, the voice conversation can start on the selected channel.
For HM Coastguard or another DSC-equipped coast station, make an individual routine call to the correct coast-station MMSI. The coast station's acknowledgement indicates the working voice channel. Tune to that channel and wait for the coast station to call you; do not begin an extended voice call on Channel 16 or Channel 70.
If the other vessel's MMSI is unknown, the current MCA small-craft route is a voice call on Channel 16, initially at low power, then move to an inter-ship channel once contact is made. The bounded Channel 13 fallback applies only after no response in that inter-ship case; it is not a general routine calling channel.
| Target | DSC selection | Voice channel decision |
|---|---|---|
| Known vessel | Individual, routine, verified MMSI | Caller proposes a suitable inter-ship channel |
| Coast station | Individual, routine, current station MMSI | Station returns the working channel |
| Unknown vessel MMSI | No guessed DSC address | Voice Channel 16, then move after contact |
Optional quick check
Section 7 of 9
After a coast station acknowledges a routine DSC call and returns a working channel, what should the yacht do?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
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