Marine communications

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Marine communications

• Marine Studies 2008
• Mr. Schultz

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Marine Radios

• Best means of summoning help
• Useful for informing groups of itinerary
• Can be used to check weather and receive warnings

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Types of comms

• VHF (Very high frequency-156MHz range) preferred
  radio for short range (20-50kms)
• Channel 16 used for emergencies and initial calls
• Marine rescue continuously monitor Channel 16 and
  67
• Channel 67 for weather
• Certificate required
• 450-1000

• Propogation no reflection from the ionosphere
• Therefore suitable for short ranges only
• Radio line of sight
• High quality sound

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Types of comms

• 27MHz Cheap, easy to operate, small boats
• Line of sight range (6-30nms)
• Most marine rescue monitor channel 27.88
• 100-250
• No certificate required
• Can be congested and subject to interference
• Satellite Expensive but excellent coverage for
  long range
• Training and operator certification necessary
• HF monitoring long term uncertain so this is
  preferred for off shore voyages

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Types of comms

• MF/HF (High frequency)- greater range
  (100-1000nms) for long distance (2-6MHz)
• 2500-4000
• Ranges depend on the frequency
• Can be reliant on atmosphere and hull of the boat
• Difficult to operate without training and
  practice
• 24/7 monitoring by States and Territories
• Certificate required

HF Radio
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Digital Selective Calling (DSC)

• An automated radio communication
• A brief burst of digitised data
• This gains contact with a station and then normal
  telephony commences
• Contains
• 1- the identity of the calling station
• 2- priority of the alert
• 3- Station being called

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Operations

• Standard procedures are used internationally
• Four types of calls
• Routine
• Distress
• Urgency
• Safety

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Routine Calls

• Used for logging on and off
• State CLEARLY
• The boat/group you are calling (eg Bramble Bay
  Coastguard) THREE TIMES
• this is (name of boat) THREE TIMES
• (message)
• over

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Distress Calls

• Only used if boat is in imminent and grave danger
  and help is required immediately eg sinking or
  fire
• mayday mayday mayday
• this is (boat name and radio call sign) spoken
  three times
• mayday
• (boat name and radio call sign)
• (boats position, nature of distress and
  assistance required)
• (other info-no. of people, description,
  intentions)

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Receipt Of distress

• MAYDAY
• Name and call sign of sender (three times)
• This is
• Name and call sign of receiver
• Received (or ROMEO) Mayday
• Then replay sent information to check

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Distress calls

• Other info
• A ship station in the vicinity should always
  acknowledge receipt UNLESS it is practicable that
  a coast station is in contact
• A ship station that is out of reach should not
  acknowledge UNLESS no one else has
  acknowledged..this station may then complete a
  MAYDAY RELAY

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Control of traffic

• Vessel in distress of station in control can
  impose silence.SEELONCE MAYDAY
• Another station .SEELONCE DISTRESS
• PRU-DONCE resumption of restricted working
• SEELONCE FEENEE.resumption of normal working

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Distress Signals

• Other ways of indicating distress
• Continuous sounding of any fog-signal
• SOS morse code ---
• Flares
• EPIRB
• V-sheet
• Slowly raising and lowering arms

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Urgency calls

• Used when urgent message needed that cannot be
  justified as Mayday eg crew member seriously ill
• pan pan, pan pan, pan pan
• hello all stations spoken three times
• this is (name and radio call sign) spoken
  three times
• (details of boats position and assistance
  required

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Safety Calls

• Used to broadcast important navigational
  information eg large floating object
• say-cure-e-tay, say-cure-e-tay, say-cure-e-tay
• hello all stations-spoken three times
• this is (name and radio call sign) spoken
  three times
• indication of channel for safety message
• (details of warning)