Ian Waugh - A Mariner\'s Guide to Marine Communications

(John Hannent) #1

Questions from Chapter 4
1 In ALRS Vo. 6 - where Pilot/Port Authority 'Frequency' shows Hi
12; 11 13 - what is the preferred calling channel?
2 What VHF channel would normally be correct for exchanging
'intership safety of navigation' messages?
3 What VHF channel is used for Routine DSC Alerts? What is the
voice channel for Distress Messages?
4 What two international VHF channels are also available for 'on-board'
communications?
5 Which of the following demonstrates a correct allocation of call signs/
calling procedure for on-board communications?
(a) , Wizard Bridge calling Deck '
(b)' Wizard Control to Wizard Alfa
(c) 'Wizard Control this is Wizard Delta
6 On marine SSB Radio, which 'Class of Emission' should be selected
for voice calls on 2182kHz and for normal, voice, radio-telephone
calls?
(a) 'H3E' (may be labelled 'AM'); or
(b) 13E' (may be labelled 'USB' or 'SSB').
7 Does Inmarsat-C offer direct connection with shore offices, or does it
use a 'store and forward' messaging system?


Answers from Chapter 4
1 Channel 12 (a working channel to the left of the semi-colon ;).
2 Ch13.
3 All VHF DSC alerts are sent on Ch70. Ch16 is used for voice Distress
messages.
4 Ch 15 and Ch17 may be used for 'on-board' communications (provided
that their use does not interfere with local pilot/port/VTS services).
5 ' Wizard Control this is Wizard Delta' is correct.
6 J3E (USB/SSB).
7 Inmarsat-C offers 'store and forward' messaging only - no direct
connection and no telephone service.


MARINE COMMUNICATIONS 73
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