JRC JHS-770S Instruction Manual page 23

USCG（United States Coast Guard）
United States Coast Guard
UTC（Universal Time Coordinated）
Universal Time Coordinated
VDR（Voyage Data Recorder）
After a maritime accident, recovered to analyze
the recorded data
conversation, VHF audio, etc.) to determine the
cause of the accident.
It can also transmit navigation management data
regularly via Inmarsat to land.
● DSC terms
Address
General term for Maritime Mobile Service Identity
number (MMSI)
This equipment uses To/From to distinguish
between the sender and receiver. It also means
the Self-ID (own ship MMSI) and Dist-ID (MMSI of
a ship in distress).
Category
Message code indicating priority of the call.
It contains types as below.
・ Routine ........General calls for routine works
・ Safety ..........Safety communications call
・ Urgency .......Urgent communications call
・ Distress........Distress call (Distress alert)
EOS（End Of Sequence）
Termination code appended to the call messages.
It contains types as below.
・ EOS.............End of sequence
・ ACK RQ.......Acknowledgement request
・ ACK BQ .......Acknowledgement responding to
the ACK RQ
ECC（Error Check Character）
Error check code appended to the end of call
messages.
This is not normally displayed, but if an error
occurs, one of the following will be displayed.
・ ECC error ....Message error
・ Ex ECC error....Expansion message error
Format
Message code indicating type of call.
It contains types as below.
・ Individual call .........Individual call
(speed, rudder, bridge
VHF（Very High Frequency）
Very High Frequency (30 - 300MHz)
VOL（Volume）
Internal speaker volume
WRC（World Radiocommunication Conference）
World Radiocommunication Conference
WMO（World Meteorological Organization）
World Meteorological Organization
WKR（Watch Keeping Receiver）
Dedicated receiver for CH70 to watch the DSC
signals.
・ Individual ACK ....... Acknowledgement
response to individual call
・ Individual NACK .... Negative acknowledgement
response to individual call
・ Semi/auto call........ PSTN connection call
・ Semi/auto ACK ...... PSTN call
acknowledgement
・ Semi/auto NACK ... PSTN call negative
acknowledgement
・ Group call .............. Call to ships having
common interest
・ All ships call........... Call to all ships
・ Distress ................. Distress call
Nature of Distress
Message code indicating type of distress when a
distress call is issued.
It contains types as below.
・ Fire ........................ Fire, explosion
・ Flooding ................ Flooding
・ Collision................. Collision
・ Grounding.............. Grounding
・ Listing .................... Risk of ship capsizing
・ Sinking .................. Sinking
・ Disabled ................ Ship inoperable/adrift
・ Undesignated ........ Undesignated distress
・ Abandoning ........... Abandoning ship
・ Piracy attack.......... Piracy attack
・ Man overboard ...... Man overboard
・ EPIRB emission .... DSC VHF EPIRB reception
Polling
Polling is a feature for routine calling.
It is used, for example, to confirm whether a ship
is existing within radio range when a coast station
requests navigational information to the ship.
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