What is the signal transmitted in H3E mode?
A. Two sidebands, upper and lower.
B. A reduced carrier and the lower sideband.
C. A full carrier and the upper sideband.
D. A full carrier and both upper and lower sidebands.
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Which of the following is true of NBDP ARQ mode?
A. This is an interactive mode.
B. Each character is repeated three times.
C. Each character is transmitted twice.
D. This mode is generally used to broadcast messages.
In radiotelephony. how many times shall the safety signal SECURITE be repeated on the announcement of a safety message?
A. Three times.
B. Three times at most.
C. Twice.
D. Six times.
What is an " area call " usually applied to?
Alert all ships in a limited sea area.
B. Send the alert to all ships.
C. Send the alert to the ships in the vicinity of a distress incident.
D. Send the alert to several ships.
How many digits are there in ship station ' s own unique MMSI which is automatically included in a DSC call?
A. 4 digits.
B. 5 digits.
C. 7 digits.
D. 9 digits.
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