Marine Courses Center

31/07/2026

📻 HOW TO TEST THE MF/HF RADIO

When was the last time you checked that your ship’s MF/HF Digital Selective Calling equipment was ready for use?

This Reel demonstrates the test sequence on the FURUNO MF/HF radio:

1️⃣ Open the test menu.
2️⃣ Select the daily test.
3️⃣ Allow the equipment to complete its internal test.
4️⃣ Run the self-check as demonstrated.
5️⃣ After successful completion, proceed with the authorised DSC test call to the selected coast station.

In this example, Alexandria Radio is selected as the coast station.

Professional Insight:

The internal self-test checks the equipment locally, while a correctly conducted DSC test call confirms communication with a coast station. Always verify the coast station identity, appropriate frequency and test-call procedure before transmission.

⚠️ Never use the distress-alert function for routine testing. Follow the equipment manual, the vessel’s Safety Management System and the Master’s standing instructions. Menu layouts and steps may differ between radio models.

31/07/2026

📡 MF/HF DSC SHORE-STATION TEST

Do you know how to confirm that your MF/HF Digital Selective Calling equipment can communicate with a coast station?

A shore-station test call provides an operational check between the ship’s MF/HF DSC equipment and a selected coast station.

Before transmitting:

1️⃣ Confirm the ship’s correct Maritime Mobile Service Identity is programmed.

2️⃣ Select a coast station that accepts DSC test calls.

3️⃣ Verify the coast station’s MMSI carefully.

4️⃣ Select the appropriate MF or HF DSC frequency for the ship’s position, propagation conditions and time of day.

5️⃣ Choose the dedicated **TEST CALL** category.

6️⃣ Transmit the test and wait for the coast station acknowledgement.

7️⃣ Record the result in the GMDSS radio log according to the vessel’s procedures.

⚠️ Never use the **DISTRESS** category for routine testing. Live MF/HF DSC testing on distress and safety frequencies should be limited to once a week to avoid unnecessary congestion.

Always follow the equipment manufacturer’s manual, the vessel’s Safety Management System and the Master’s standing instructions. Menu layouts vary between radio models.

📊 POLL: Have you performed an MF/HF DSC shore-station test onboard?

🔘 Yes, regularly
🔘 Yes, during training
🔘 I have only observed it
🔘 Not yet

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30/07/2026

🌊 Can you identify a buoy at night by its light colour?

Buoy lights allow navigators to recognise different marks when their shapes and colours are difficult to see. In IALA Region A, the principal light colours shown in this lesson are red, green, yellow and white.

🔴 Port-hand lateral marks show red lights.

🟢 Starboard-hand lateral marks show green lights.

🟡 Special marks show yellow lights.

⚪ Cardinal marks show white lights:

• North Cardinal: black above yellow
• East Cardinal: black–yellow–black
• South Cardinal: yellow above black
• West Cardinal: yellow–black–yellow

Professional Insight:

Light colour is only the first clue. During an actual watch, the Officer of the Watch must also identify the light’s rhythm and period and compare the complete characteristic with the chart, Electronic Navigational Chart and List of Lights.

Never identify a navigational mark using light colour alone.

Which buoy light colour do you recognise most quickly at night?

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30/07/2026

27/07/2026

🚢 Before identifying a lateral mark, ask yourself one essential question:

Which way is the general direction of buoyage?

The direction of buoyage determines how lateral marks must be interpreted. It normally follows the direction taken when approaching a harbour, river or waterway from seaward.

In IALA Region A, when proceeding in the direction of buoyage:

🔴 Red can-shaped marks indicate the port-hand side.

🟢 Green conical marks indicate the starboard-hand side.

But remember: if your vessel reverses its heading, the marks do not change their colours or identities—only their positions relative to your vessel change.

⚠️ Lateral marks define the sides of the route, but they do not guarantee sufficient depth throughout the entire area between them. Always check the chart, ENC and relevant nautical publications.

Professional takeaway:

Read the direction before the colours.

Would you make the correct decision if your vessel were proceeding against the direction of buoyage?

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26/07/2026

⚓ COLREGS Navigation Lights & Day Shapes — Quick Reference Guide

Correct navigation lights and day shapes are essential for identifying a vessel's status, movement, and operational condition at sea.

This quick reference includes the lighting and shapes for:

✅ Power-driven vessels
✅ Sailing vessels
✅ Air cushion vessels & WIG craft
✅ Towing vessels & composite units
✅ Fishing vessels (trawling / non-trawling)
✅ Vessels not under command (NUC)
✅ Vessels restricted in their ability to manoeuvre (RAM)
✅ Dredging vessels
✅ Mine clearance vessels
✅ Vessels constrained by their draught (CBD)
✅ Pilot vessels
✅ Vessels aground

Learning these signals is essential for every Deck Officer, OOW, and maritime student preparing for exams and safe watchkeeping.

🚢 Recognize the lights. Identify the vessel. Navigate safely.

25/07/2026

🦺 Can you confirm that a lifejacket is suitable just by looking at its colour?

No. The markings provide essential information about the lifejacket’s approval, intended wearer and correct use. Before relying on any lifejacket, the crew must confirm that its markings are permanent, legible and consistent with the ship’s approved life-saving equipment.

🔎 What should you check?

✅ Approval or conformity marking required by the applicable Administration.
✅ Manufacturer and model identification, where provided.
✅ Intended size range, shown by weight, height or both.
✅ Clear INFANT, CHILD or ADULT identification as applicable.
✅ Infant or child symbol on the relevant lifejackets.
✅ Donning instructions and operating information provided by the manufacturer.
✅ Compatibility with the fitted light, whistle and securing arrangements.
✅ For inflatable lifejackets: inflation system, cylinder condition, status indicator and servicing information.

⚠️ Important correction

The figures 50 N, 100 N, 150 N and 275 N describe nominal buoyancy classes used under particular lifejacket standards. They do not automatically prove that a lifejacket is SOLAS approved.

N means newtons—the unit used to express buoyant force. A higher number means greater nominal buoyancy, but approval depends on the complete applicable standard, testing and certification—not the buoyancy number alone.

💡 Professional Insight

SOLAS lifejackets are assessed for performance, including their ability to support the wearer and turn an unconscious, face-down person towards a safe face-up position. Therefore, never select or accept a shipboard lifejacket solely because it displays 150 N or 275 N.

🚢 Onboard Example

During an inspection, an Officer of the Watch finds a lifejacket with a faded size marking and an unreadable approval label. Even if the jacket appears undamaged, it should be reported and handled according to the ship’s approved procedures—it must not simply be assumed suitable.

⚓ Safety Takeaway

A lifejacket without clear, valid markings creates uncertainty about its approval, size and intended use. When lives depend on the equipment, uncertainty is unacceptable.

What are the first three markings you check during a lifejacket inspection?

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25/07/2026

🦺 Would every person onboard have the correct lifejacket if an emergency happened now?

Carrying enough lifejackets is not simply about matching the ship’s capacity. The equipment must suit the people onboard, remain readily accessible and be correctly positioned for immediate use.

Key requirements include:

✅ One suitable lifejacket for every person onboard.
✅ Additional lifejackets for persons on watch and at remotely located survival-craft stations.
✅ Passenger ships: child lifejackets equal to at least 10% of the passengers—or enough for every child, whichever is greater.
✅ Passenger ships on voyages under 24 hours: infant lifejackets equal to at least 2.5% of passengers.
✅ Passenger ships on voyages of 24 hours or more: one infant lifejacket for every infant onboard.
✅ Passenger ships must also carry additional lifejackets for at least 5% of all persons onboard, stowed conspicuously on deck or at muster stations.
✅ If adult lifejackets do not fit persons up to 140 kg with a chest girth up to 1,750 mm, sufficient suitable securing accessories must be available.

💡 Professional Insight

The 140 kg and 1,750 mm figures do not mean that every ship must carry a separate “oversize lifejacket” for each person. They mean that suitable securing accessories are required when the supplied adult lifejackets are not designed for those dimensions.

🚢 Onboard Example

Before departure, the Officer of the Watch checks the bridge lifejacket, while the responsible officer confirms that lifejackets at remote stations are accessible, clearly indicated and suitable for the passengers actually onboard—including children and infants.

⚠️ Safety Takeaway

A lifejacket that is inaccessible, incorrectly sized or missing when needed cannot save a life. Correct quantity, correct size and correct stowage all matter.

Could you locate and correctly don your nearest lifejacket without assistance?

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25/07/2026

Would you trust one screen with your ship’s safety?

AIS—Automatic Identification System—can help the Officer of the Watch identify transmitting vessels and understand the developing traffic situation.

But AIS does not see everything, and it does not make collision-avoidance decisions.

Key points:

Not every vessel carries or transmits AIS.
Identity, navigational status and destination may be entered incorrectly.
Position and motion data depend on connected sensors.
AIS-derived CPA and TCPA must be cross-checked.
A proper lookout remains essential.
Avoiding action must follow the COLREGs.

Professional Insight

AIS usually reports course and speed over ground. Radar or Automatic Radar Plotting Aid information may describe target movement differently. Current, wind, sensor quality and target manoeuvres can create important differences between the two displays.

Onboard example

AIS identifies a target as Ocean Trader, but its AIS vector conflicts with the radar plot. The correct response is not to select the more convenient answer. The Officer of the Watch should verify the target visually when possible, check radar acquisition and settings, review AIS data quality and assess risk using all available information.

Safety takeaway: AIS helps—it does not decide.

What would you check first if the AIS and radar vectors disagreed?

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