C. Frequency modulation is subject to interference by atmospheric noise. D. High level mixing of the final amplifier signal and the information signal. B
391. Which statement best describes amplitude modulation?
A. The character data from the terminal is changed to audio tones.
B. The frequency is varied in synchronization with the modulating signal.
C. The information signal changes the amplitude but does not change the carrier frequency.
D. The amplitude of the carrier is changed but there is still only a single frequency being transmitted. C
392. What equipment is associated with the land or terrestrial system? A. EPIRB B. VHF/MF/HF C. INMARSAT-C D. GPS B
393. A DSC call with the MMSI number 412888111 is likely to:
A. A coast station B. Call a Chinese vessel. C. A group call for ship stations. D. Call a Japanese vessel.
B
394. A DSC call with the MMSI number 036688811 is:
A. A group call for ship stations. B. A vessel operating in Sea Area A3. C. A coast station D. An intercoastal call.
A
395. The MMSI of MRCC Shanghai is:
A. 412210011 B. 004122100 C. 004122111 D. 041222111 B
396. The MMSI of MRCC Dalian is:
A. 412310011 B. 004121300 C. 004121311 D. 04121320 B
397. A DSC call with the MMSI number 003669991 is:
A. A vessel operating in Sea Area A3. B. A group call for ship stations. C. A coast station D. An intercoastal call.
C
398. What is the purpose of a DSC control unit?
A. In some circumstances, it will automatically acknowledge routine DSC calls. B. It decodes and displays the message.
C. I twill store the message internally until manually retrieved. D. All of these D
399. What is the fundamental purpose of a coast radio station?
A. To provide a delivery in E-mail service for ships with routine, safety, urgency, or distress message traffic. B. To provide continuous digital selective calling coverage.
C. To automatically connect a vessel placing an INMARSAT call with the station being called. D. To coordinate search and rescue communications. B
400. What statement best describes modulation? A. Imposing intelligence onto a radio carrier signal. B. Changing mark-space to 1 and 0.
C. Adjusting the frequency to the optimum band for long distance communications.
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D. Converting the carrier from a low frequency to a higher frequency. A
第五章 海上安全信息
401. Which is the B1 Code of Hong Kong NATEX station? A. R. B. O. C. N. D. L D
402. Which is the B1 Code of Sanya NATEX station? A. R. B. O. C. N. D. M D
403. Which is the B1 Code of Fuzhou NATEX station? A. R. B. O. C. N. D. L B
401. Which is the B1 Code of Shanghai NATEX station? A. R. B. O. C. N. D. Q D
405. Which is the B1 Code of Guangzhou NATEX station? A. R. B. O. C. N. D. L C
406. Which is the B1 Code of Dalian NATEX station? A. R. B. O. C. N. D. L A
407. How are Enhance Group Calls transmitted?
A. By COSPAS satellites. B. By INMARSAT satellites.
C. By NAVTEX shore stations. D. By HF NBDP shore stations and INMARSAT satellites.
B
408. What type of information does SafetyNET promulgate?
A. PORT advisories. B. Traffic Lists. C. MSI. D. AMVER C
409. In general terms, which system is necessary for the reception of MSI (Maritime Safety Information) by ships trading in the middle oceans?
A. HF NBDP B. HF Weather facsimile. C. EGC in INMARSAT system D. All of these
D
410. What action should a GMDSS operator take when SafetyNET distress or urgency messages are received by the vessel’s EGC receiver?
A. No immediate action is required by the operator since the transmission will be automatically acknowledged by the receiving vessel.
B. Aural and visual alarms are activated, and require manual deactivation by operator.
C. A periodic alarm tone will be heard until the radio operator prints the message from the unit’s memory. D. All of these. B
411. What is the primary equipment for receiving MSI?
A. NAVTEX B. SART C. EPRIB D. INMARSAT-B A
412. An automated system that is capable of addressing message to ships in pre-determined groups or to all
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ships in both fixed and variable geographic areas is know as what?
A. NAVTEX B. AFRTS C. EGC D. NAVAREAs. C
413. What frequencies are used for receiving HF MSI?
A. HF MSI is transmitted on a primary frequency of 518 KHz and on a secondary frequency of 490 KHz. B. HF MSI is transmitted on 8414.5 KHz plus one other (undesignated) HF frequency.
C. HF MSI is transmitted on the third ITU channel in each HF ban (2, 4, 6, 8, 12, 16 and 22 MHz). D. HF MSI is transmitted on certain dedicated frequencies. D
414. Which of the following MF frequencies is internationally allocated for use for transmitting NAVTEX-type broadcasts?
A. 518 KHz using FEC mode. B. 4209.5 KHz using FEC mode. C. 486 KHz using FEC mode in China D. All of these. A
415. Which is the following HF frequencies is internationally allocated for use for transmitting NAVTEX-type broadcasts?
A. 4209.5 KHz using ARQ mode. B. 4209.5 KHz using FEC mode.
C. 8414.5 KHz plus one other. D. NAVTEX-type broadcasts are not transmitted on any HF frequency.
B
416. What system may be useful for messages, such as local storm warnings or a store-to-ship distress alert, for which it is inappropriate to alert all ships in the satellite coverage area?
A. EGC B. NAVTEX C. AMVER D. DSC A
417. What kind(s) of broadcasts are available through SafetyNET? A. MSI and message to pre-defined groups of subscribers. B. MSI and vessel traffic lists.
C. Hourly weather broadcasts from coast radio stations. D. Coastal weather broadcasts. A
418. What is the purpose of Maritime Safety Information broadcasts? A. To provide hourly weather broadcasts from coast radio stations. B. To provide traffic lists from coast radio stations.
C. To maximize reception of mobile distress alerts, weather forecasts, coastal warning and similar information.
D. To allow the transmission of message too pre-defined groups of subscribers. C
419. Which non-satellite system promulgates Maritime Safety Information?
A. AMVER B. SafetyNET C. NAVTEX D. NAVAREA C
420. Which satellite system promulgates Maritime Safety Information?
A. AMVER B. NAVTEX C. SafetyNET D. INMARSAT-M SES C
421. Frequencies specified for MSI (Maritime Safety Information): A. Shall be used by authorized coast stations form broadcasting MSI.
B. Shall be used by a ship station for reporting MSI to a public coast station for relay to the U.S. Coast
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Guard.
C. Shall be used by a ship station for transmitting a distress relay. D. All of these. A
422. EGC has to do with:
A. VHF B. MF/HF C. INMARSAT D. NBDP C
423. If your NAVTEX receiver becomes disabled you can:
A. Copy MSI (Maritime Safety Information) broadcasts using INMARSAT-F SafetyNET. B. Copy MSI broadcasts using HF NBDP or INMARSAT-C SafetyNET. C. Copy NAVTEX on any NBDP Telex receiver on 518 KHz
D Copy MSI broadcasts using HF NBDP or INMSARSAT-C SafetyNET or copy NAVTEX on any NBDP Telex receiver on 518 KHz.
D
424. NAVAREAs referred to in NAVTEX are the same as used in:
A. INMARSAT SafetyNET. B. GMDSS sea areas. C. International Vessel Traffic Service D. INMARSAT ocean regions.
A
425. A vessel operating in the vicinity of Italy, in which NAVAREA she should be located? A. X B. XI C. IV D. III D
426. A ship operating in an area not covered by NAVTEX? A. Is exempt from copying MSI (Maritime Safety Information).
B. Must be capable of receiving MSI via HF NBDP or INMARSAT-C.
C. Is exempt from copying MSI if they are using an automated chart correction system and guard 2182.0 KHz.
D. Must be capable of receiving MSI via HF NBDP or INMARSAT-F. B
427. A vessel using SafeyNET should:
A. Set the receiver to your present Ocean Region.
B. Notify the NAVAREA coordinator you are using SafetyNet for MSI (Maritime Safety Information) C. Set the receiver to your destination Ocean Region.
D. Notify the NAVAREA coordinator you are using SafetyNet for MSI (Maritime Safety Information) and set the receiver to your destination Ocean Region.
A
428. In using SafetyNet for MSI (Maritime Safety Information):
A. If you fail to log-in with Ocean Region you will receive only unscheduled urgent and distress broadcasts. B. To receive scheduled and unscheduled broadcasts you must log-in with your Ocean Region Net Control Station (NCS).
C. Your satellite receiver must have Enhanced Group Calling (EGC) capability. D. All of these. D
429. Frequencies for receiving HF MSI (Maritime Safety Information) are: A. The same as used for NAVTEX. B. Specified HF Telex frequencies.
C. The same as used for general Telex using FEC.
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D. Specified HF voice frequencies. B
430. Frequencies for receiving MSI (Maritime Safety Information) internationally are: A. MF NBDP frequencies specified for MSI. B. MF SSB frequencies specified for MSI. C. HF NBDP frequencies specified for MSI. D. HF SSB frequencies specified for MSI. C
431. What system can provide an automated service in coastal waters where it may not be feasible to establish the NAVTEX service or where shipping density is too low to warrant its implementation?
A. AMVER B. SafetyNet C. VHF DSC D. ARQ SITOR. B
432. Which of the following provides a unique automated system capable of addressing messages to pre-determined groups of ships or all vessels in both fixed and variable geographic area?
A. NAVTEX. B. AFRTS. C. EGC. D. NAVAREAs. C
433. What is an EGC “ENID”?
A. This identifies the vessel’s selective calling (selcall) number.
B. This number is used for receiving news and other optional services in FleetNET. C. This is the INMARSAT number that is assigned to a unit for incoming calls.
D. This is the vessel’s INMARSAT registration number for accounting authority purposes. B
434. Which function should be performed only by the holder of a GMDSS Electronic certificate on a NAVTEX receiver?
A. Replacement of the processor. B. Replacement of fuses.
C. Self-diagnostic processor and printer tests. D. Erasing stored message IDs. A
435. Which message subject matter cannot be disabled by the operator of a NAVTEX receiver? A. Navigational warnings. B. Meteorological warnings. C. Search and rescue information. D. All of these. D
436. What equipment is utilized to transmit Enhanced Group Calls?
A. COAPAS satellite B. HF SITOR shore stations. C. NAVTEX shore stations. D. INMARSAT satellite. D
437. Aboard ship, SafetyNET messages can be received by which equipment?
A. VHF DSC B. NAVTEX receiver C. Dedicated receiver or optional receiver integrated in vessel’s SES. D. All of these. C
438. Which is the frequency used in internationally for NAVTEX-type MSI (Maritime Safety Information) transmissions?
A. 4125.0 KHz using FEC mode. B. 490 KHz using FEC mode. C. 4209.5 KHz using ARQ mode. D. 4125.0 KHz using FEC mode. B
439. Which is the frequency used in internationally for NAVTEX-type MSI (Maritime Safety Information) transmissions?
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