Login or Register for FREE!
Subelement J

MF-HF Equip. and Comms:

Section 89

MF-HF ARQ Operation - Calling a Coast Station

Which of the following would be a valid SELCAL for use in ARQ communications?

  • Correct Answer
    1106
  • 212420 WHAQ X.
  • Four marks (ones) and three spaces (zeroes) forming the binary signal "1001101".
  • This is established by the communications protocol used with the modem.
This question does not yet have an explanation! Register to add one

Tags: none

Once ARQ communication with the coast radio station has been established, which of the following events will most likely take place?

  • The vessel then requests the coast radio station's SELCAL so that communication can be set up on the appropriate working channel.
  • Correct Answer
    After exchanging answer-backs (WRU-AAB) with the vessel, the coast radio station transmits GA+?.
  • Since communication has already shifted to the working channel, the vessel then transmits the subscriber number and text of the message to be sent for the coast radio station to store and forward.
  • The coast radio station will transmit a menu of commands such as DIRTLX+, OBS+ or AMV+ so the ship can select the desired action.
This question does not yet have an explanation! Register to add one

Tags: none

Which of the following methods will give a GMDSS Radio Operator the best indication of whether ARQ communication can be established with a coast radio station?

  • Referring to propagation charts will tell the Operator when the eruption of communication shattering solar flares will occur.
  • Selecting a frequency in the MF band averts interference from severe static discharges.
  • Correct Answer
    Monitor the coast radio station's "free signals" and call on the frequency on which the loudest and most consistent signals are heard.
  • Re-position the antenna toward the coast radio station and press the "call request" button.
This question does not yet have an explanation! Register to add one

Tags: none

When placing a TELEX call to a Coast Station, you should always:

  • Choose the closest station.
  • Tune the transmitter on another frequency.
  • Wait until the coast station sends his traffic list.
  • Correct Answer
    Make sure the frequency is not occupied with normal traffic.
This question does not yet have an explanation! Register to add one

Tags: none

What is the best method for a GMDSS Radio Operator to determine which SITOR (NBDP) station to contact for the purpose of sending a chargeable message or cable?

  • Correct Answer
    Listen to each station's “free signals” and call the strongest station.
  • Listen to each station's voice announcement and determine which channel(s) will be monitored.
  • Listen to each station's MSI broadcast to determine which public correspondence station to contact.
  • Listen to the U.S. Coast Guard's traffic list to determine which Coast Guard station will handle commercial traffic.
This question does not yet have an explanation! Register to add one

Tags: none

Which statement is correct regarding HF SITOR (NBDP) under GMDSS?

  • Distress communications other than directly to the Coast Guard or other coast stations on the channels that they normally guard, should be in the broadcast SSB mode.
  • Correct Answer
    Safety communications by direct-printing telegraphy should be in the ARQ mode when communicating with the U.S. Coast Guard or other coast stations on channels that they normally guard.
  • The ARQ mode may not be used subsequently to the FEC mode even when it is advantageous to do so.
  • Distress communications other than directly to the Coast Guard or other coast stations on the channels that they normally guard, should be in the broadcast FEC or SSB mode.
This question does not yet have an explanation! Register to add one

Tags: none

Go to 88 Go to 90