Channel 16
Channel 16 is the main distress, urgency, safety, and calling channel. Routine calls should move to a suitable working channel as soon as contact is established.
- Distress and calling
- Keep transmissions short
Marine Radio revision module 4 of 10
16
Channels & Frequencies
Channel 16, Channel 70, marina/port channels, intership working channels, and when to move off the calling channel.
Channel 16Channel 70 DSC
9 guided lessons · 19 practice questions · 19 flashcards
3 outcomes · self-guided revision
- Explain channel 16, Channel 70, marina/port channels, intership working channels, and when to move off the calling channel.
- Apply Channel 16 to a realistic onboard situation.
- Recall the core check: distress and calling.
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Lesson summaries
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Channel 70
Channel 70 is used for DSC digital signalling. It is not a voice channel.
- DSC only
- No voice on Channel 70
Working Channels
Marinas, ports, vessel traffic services, and ship-to-ship conversations use assigned working channels. The correct channel depends on the area and service.
- Use local information
- Agree a working channel
Calling, Distress, And DSC Channels
Channel 16 is the international distress, safety, and calling voice channel. Channel 70 is for DSC digital signalling, not voice. Confusing those two is one of the fastest ways to show we...
- Channel 16: voice distress, safety, and calling.
- Channel 70: DSC digital signalling only.
Intership And Working Channels
Intership channels such as 6, 8, 72, and 77 are commonly used for ship-to-ship working traffic where appropriate. Local channel plans still matter, and some channels have special uses in...
- Use working channels for the working conversation.
- Check almanac, harbour guidance, and local instructions.
Marina, Port, And Local Channels
Marinas, ports, harbour authorities, bridges, locks, and traffic services may use local working channels. Some UK marina traffic uses Channel 80 or M channels, but you must check the loca...
- Check the almanac or local notices before arrival.
- Use the harbour or marina's published channel.
Channel Discipline
Channel discipline protects safety traffic. Listen before transmitting, keep the message brief, and do not use calling or distress channels for avoidable chatter.
- Listen before transmitting.
- Use correct priority and channel.
Simplex, Duplex, And Channel Purpose
A simplex channel uses the same working frequency arrangement for both directions, so only one station speaks at a time. A duplex channel uses paired frequencies for ship and coast direct...
Read the full lesson: Simplex, Duplex, And Channel PurposeChannel 13 Is A Navigation-Safety Fallback, Not A Second Channel 16
When another ship's MMSI is unknown, MCA small-craft guidance says to call by voice on Channel 16 using low power and move to an inter-ship channel once contact is made. If there is no re...
- Known MMSI: prefer an Individual DSC routine call and nominate an inter-ship channel.
- Unknown MMSI: low-power voice call on Channel 16, then move off promptly.
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