All the distress message should be preceded by _________
A. PAN PAN
B. SECURITE
C. MAYDAY
D. MEDICO
查看答案
_________ is (are) frequency (frequencies) can be used for routine DSC calling between ships, and between ship and shore respectively.
A. 2177 kHz.
B. 2177 kHz and 2189.5 kHz used in pairs only.
C. 156.525 Mhz.
D. 2177 kHz/2177 kHz and 2177 kHz/2189.5 kHz used in pairs.
The frequency 2174.5 kHz in NBDP service is used for _________.
A. Distress and safety traffic using narrow-band direct-printing telegraphy exclusively
B. Transmissions of information regarding the safety of navigation and weather warnings
C. Distress and safety traffic in radiotelephony
D. Transmissions of the international NAVTEX system
In general terms, all the media listed below are used to receive MSI, except _________.
A. The international NAVTEX system.
B. The Inmarsat Safety NET system.
C. HF NBDP.
D. GLONASS receivers at sea.
_________ may be provided by Inmarsat Standard-C via traditional facsimile service.
A. Transferring texts
B. Transferring voices
C. Transferring images
D. Transferring pictures
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