RYA SRC DSC Operations 5 — Questions and Answers
Question 1: When programming an MMSI into a DSC VHF radio, who in the UK should vessels register their MMSI with?
- Ofcom (Correct answer)
- MCA
- RYA
- Trinity House
Correct answer: Ofcom
In the UK, vessel MMSIs are allocated and registered through Ofcom, which is the communications regulator responsible for maritime radio licensing.
Question 2: A DSC individual call to another vessel is typically followed by voice communication on which channel?
- A working channel agreed in the DSC call or by prior arrangement (Correct answer)
- Channel 16 exclusively
- Channel 70
- Channel 67
Correct answer: A working channel agreed in the DSC call or by prior arrangement
After a DSC individual call, both vessels switch to a working channel that is proposed in the DSC message or agreed by prior arrangement.
Question 3: What does a flashing DSC distress alert indicator on your radio require you to do?
- Acknowledge the alert and prepare to render assistance or relay (Correct answer)
- Ignore it unless it is repeated three times
- Immediately send your own DSC distress alert
- Switch the radio off and back on to reset it
Correct answer: Acknowledge the alert and prepare to render assistance or relay
When a DSC distress alert is received, the operator must acknowledge it and assess whether to render assistance or relay the alert to the coast guard.
Question 4: Which DSC call category is used when a person has fallen overboard and immediate danger to life is present?
- Distress (Correct answer)
- Urgency
- Safety
- Routine
Correct answer: Distress
A man overboard situation involving immediate danger to life warrants a Distress category DSC call and a MAYDAY voice call.
Question 5: A DSC group call is sent using what type of identifier?
- A group MMSI shared by vessels in a specific fleet or area (Correct answer)
- Each individual vessel's MMSI listed sequentially
- The coast station's MMSI prefixed with a 0
- A broadcast identifier of all nines
Correct answer: A group MMSI shared by vessels in a specific fleet or area
A group MMSI is a special MMSI programmed into vessels belonging to a specific group, such as a ferry fleet, allowing DSC calls to reach all group members simultaneously.
Question 6: How should an accidental DSC distress alert be cancelled to prevent a false alarm response?
- Immediately call the coast guard on Channel 16 and advise it was sent in error (Correct answer)
- Send a second DSC alert to overwrite the first
- Switch the radio to Channel 70 and transmit a cancellation
- Turn the radio off for two minutes
Correct answer: Immediately call the coast guard on Channel 16 and advise it was sent in error
If a distress alert is sent accidentally, the operator must immediately contact the coast guard on Channel 16 by voice and state that the alert was sent in error.
Question 7: Which of the following best describes the role of Channel 70 in DSC operations?
- It is reserved exclusively for DSC digital calling and must never be used for voice (Correct answer)
- It is the primary voice distress channel
- It is used for DSC alerts and also for routine voice traffic
- It is a scanning channel used to monitor commercial shipping
Correct answer: It is reserved exclusively for DSC digital calling and must never be used for voice
Channel 70 is internationally designated exclusively for DSC digital alerting and must never be used for voice transmissions.
RYA SRC DSC Operations 5
When programming an MMSI into a DSC VHF radio, who in the UK should vessels register their MMSI with?