Element 9 Practice Test

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What type of coaxial cable would be most appropriate for a long transmission line run?

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Unofficial practice questions, not affiliated with the Federal Communications Commission (FCC). Bank checked October 2, 2026.

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All 297 questions

A: VHF-DSC Equipment & Operation 59

  • A masthead antenna with a base loading coil appears shorted to an ohmmeter check. What might this indicate? FCC Commercial Element 9 question pool (file headed September 2012), question 10A3, key topic 10: Antenna Systems
  • A mismatched antenna system can degrade marine VHF radio performance. Antenna system matching can be analyzed by determining the Standing Wave Ratio (SWR). Which of the following is the best test procedure to determine the VHF antenna system SWR? FCC Commercial Element 9 question pool (file headed September 2012), question 7A3, key topic 7: Transmitter Faults-1
  • A modulation index set to less than 1 to 1 may result in what? FCC Commercial Element 9 question pool (file headed September 2012), question 6A4, key topic 6: Transmitter Technology
  • A spectrum analyzer (SPECAN) can be a useful test instrument to troubleshoot a marine VHF radio. Which of the following is the best procedure to evaluate the input/output stages of a marine VHF transmitter? FCC Commercial Element 9 question pool (file headed September 2012), question 8A3, key topic 8: Transmitter Faults-2
Show all 297 questions (293 more)

A: VHF-DSC Equipment & Operation, continued

  • Antenna system matching can be analyzed by determining the Standing Wave Ratio (SWR). Which of the following is the best test procedure to measure the SWR of a marine VHF antenna system? FCC Commercial Element 9 question pool (file headed September 2012), question 7A2, key topic 7: Transmitter Faults-1
  • How is pre-emphasis used in an FM transceiver? FCC Commercial Element 9 question pool (file headed September 2012), question 6A3, key topic 6: Transmitter Technology
  • How many sidebands does a VHF FM transmitter have? FCC Commercial Element 9 question pool (file headed September 2012), question 6A6, key topic 6: Transmitter Technology
  • How might a DSC radio check be accomplished with a coast station? FCC Commercial Element 9 question pool (file headed September 2012), question 9A3, key topic 9: Digital Selective Calling
  • It becomes necessary to construct a temporary VHF marine antenna. What should be the approximate length of the antenna? FCC Commercial Element 9 question pool (file headed September 2012), question 10A1, key topic 10: Antenna Systems
  • Using a frequency counter with an accuracy of 2 ppm — which of the following are within legal tolerance for the frequencies of 156.800 MHz and 156.525 MHz? FCC Commercial Element 9 question pool (file headed September 2012), question 1A5, key topic 1: Frequency and Bandwidth
  • Using a frequency counter with an accuracy of 5 ppm — which of the following are within legal tolerance for the frequencies of 156.875 MHz and 157.200? FCC Commercial Element 9 question pool (file headed September 2012), question 1A6, key topic 1: Frequency and Bandwidth
  • What are the correct VHF Channels and Frequencies for Calling/Distress, DSC and bridge-to-bridge operations? FCC Commercial Element 9 question pool (file headed September 2012), question 1A1, key topic 1: Frequency and Bandwidth
  • What condition may be indicated if a VHF radio cannot contact nearby stations on any channel, an inline wattmeter indicates 25 watts output (HIGH power mode), and no modulation is heard when the transmitted signal is monitored with an external receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 8A1, key topic 8: Transmitter Faults-2
  • What condition may be indicated if a VHF radio cannot contact nearby stations, an inline wattmeter indicates less than 1 watt output (HIGH power mode), and nominal voltage (e.g., 12.8 vdc) is applied to the VHF radio power input line? FCC Commercial Element 9 question pool (file headed September 2012), question 8A2, key topic 8: Transmitter Faults-2
  • What condition may be indicated if a VHF radio is unable to contact nearby stations and an inline wattmeter indicates power outputs of 1 watt (LOW power) mode and 8.5 watts (HIGH power) mode with +12.8 vdc applied to the radio’s DC line? FCC Commercial Element 9 question pool (file headed September 2012), question 7A1, key topic 7: Transmitter Faults-1
  • What condition may cause a significant loss in VHF receiver sensitivity? FCC Commercial Element 9 question pool (file headed September 2012), question 5A1, key topic 5: Receiver Faults-2
  • What condition may cause distortion in the modulator stage of a marine VHF transmitter? FCC Commercial Element 9 question pool (file headed September 2012), question 8A5, key topic 8: Transmitter Faults-2
  • What condition may cause noisy operation of a VHF receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 5A6, key topic 5: Receiver Faults-2
  • What condition may exist if a VHF radio is operational in receive mode but unable to transmit? FCC Commercial Element 9 question pool (file headed September 2012), question 7A6, key topic 7: Transmitter Faults-1
  • What condition may indicate a VHF receiver fault? FCC Commercial Element 9 question pool (file headed September 2012), question 5A5, key topic 5: Receiver Faults-2
  • What condition may indicate voltage controlled oscillator failure in the synthesizer of a VHF transmitter? FCC Commercial Element 9 question pool (file headed September 2012), question 7A5, key topic 7: Transmitter Faults-1
  • What condition may prevent a VHF radio receiver from receiving a weak signal? FCC Commercial Element 9 question pool (file headed September 2012), question 4A5, key topic 4: Receiver Faults-1
  • What condition may prevent a VHF radio receiver from staying tuned to the desired channel? FCC Commercial Element 9 question pool (file headed September 2012), question 4A1, key topic 4: Receiver Faults-1
  • What fault may exist if a VHF radio receiver fails to produce audible output from the speaker and the squelch control has no effect? FCC Commercial Element 9 question pool (file headed September 2012), question 4A2, key topic 4: Receiver Faults-1
  • What is a disadvantage when using high gain VHF antennas? FCC Commercial Element 9 question pool (file headed September 2012), question 10A6, key topic 10: Antenna Systems
  • What is indicated if a VHF radio fails to receive nearby stations and a voltmeter connected between the positive side of a radio’s DC line and ground reads zero line voltage? The fuse in the VHF radio also reads zero when checked with an ohmmeter. FCC Commercial Element 9 question pool (file headed September 2012), question 4A3, key topic 4: Receiver Faults-1
  • What is meant by “full quieting” in a FM VHF receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 3A6, key topic 3: Receiver Technology
  • What is the allowed frequency tolerance for the DSC carrier frequencies? FCC Commercial Element 9 question pool (file headed September 2012), question 1A4, key topic 1: Frequency and Bandwidth
  • What is the assigned channel spacing for VHF channels? FCC Commercial Element 9 question pool (file headed September 2012), question 1A3, key topic 1: Frequency and Bandwidth
  • What is the correct frequency shift and sub-carrier for VHF-DSC? FCC Commercial Element 9 question pool (file headed September 2012), question 9A1, key topic 9: Digital Selective Calling
  • What is the correct modulation rate and index of modulation for VHF-DSC? FCC Commercial Element 9 question pool (file headed September 2012), question 9A2, key topic 9: Digital Selective Calling
  • What is the frequency separation between Transmit and Receive frequencies on a duplex channel? FCC Commercial Element 9 question pool (file headed September 2012), question 1A2, key topic 1: Frequency and Bandwidth
  • What is the function of a properly adjusted limiter circuit? FCC Commercial Element 9 question pool (file headed September 2012), question 3A3, key topic 3: Receiver Technology
  • What is the maximum allowable deviation of a marine VHF transmitter? FCC Commercial Element 9 question pool (file headed September 2012), question 6A1, key topic 6: Transmitter Technology
  • What is the modulation index? FCC Commercial Element 9 question pool (file headed September 2012), question 6A2, key topic 6: Transmitter Technology
  • What is the most common type of coax connector used on VHF transceivers? FCC Commercial Element 9 question pool (file headed September 2012), question 10A4, key topic 10: Antenna Systems
  • What is the most common type of emission for shipboard VHF-DSC transceivers? FCC Commercial Element 9 question pool (file headed September 2012), question 6A5, key topic 6: Transmitter Technology
  • What is the proper adjustment of the squelch control for maximum sensitivity? FCC Commercial Element 9 question pool (file headed September 2012), question 2A4, key topic 2: Controls and Functions
  • What is the purpose of the Dual Watch function? FCC Commercial Element 9 question pool (file headed September 2012), question 2A3, key topic 2: Controls and Functions
  • What is the purpose of the USA-INT switch? FCC Commercial Element 9 question pool (file headed September 2012), question 2A1, key topic 2: Controls and Functions
  • What is the time diversity reception interval for a VHF-DSC call? FCC Commercial Element 9 question pool (file headed September 2012), question 9A5, key topic 9: Digital Selective Calling
  • What may be indicated if a VHF radio operates normally but the transmitter produces nearly zero RF output in the high power mode on all marine channels? FCC Commercial Element 9 question pool (file headed September 2012), question 7A4, key topic 7: Transmitter Faults-1
  • What may happen if the USA-INT control is left on INT when in U.S. waters? FCC Commercial Element 9 question pool (file headed September 2012), question 2A2, key topic 2: Controls and Functions
  • What might a voltmeter indicate when testing a DSC circuit for an outgoing message data stream? FCC Commercial Element 9 question pool (file headed September 2012), question 9A6, key topic 9: Digital Selective Calling
  • What ohmmeter reading may indicate a faulty component in a VHF receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 5A4, key topic 5: Receiver Faults-2
  • What terms are used to describe a device used to test the RF power output of a marine VHF transmitter without emitting a signal on the air? FCC Commercial Element 9 question pool (file headed September 2012), question 8A6, key topic 8: Transmitter Faults-2
  • What type of coaxial cable would be most appropriate for a long transmission line run? FCC Commercial Element 9 question pool (file headed September 2012), question 10A5, key topic 10: Antenna Systems
  • What would be considered a normal sensitivity for 10 db of quieting in a VHF marine receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 3A5, key topic 3: Receiver Technology
  • Which in-line RF power reading indicates the proper operation of a VHF marine transmitter? FCC Commercial Element 9 question pool (file headed September 2012), question 8A4, key topic 8: Transmitter Faults-2
  • Which of the following are true about SINAD measurements? FCC Commercial Element 9 question pool (file headed September 2012), question 3A4, key topic 3: Receiver Technology
  • Which of the following best describes a VHF collinear array? FCC Commercial Element 9 question pool (file headed September 2012), question 10A2, key topic 10: Antenna Systems
  • Which of the following best describes the “Capture effect?” FCC Commercial Element 9 question pool (file headed September 2012), question 3A1, key topic 3: Receiver Technology
  • Which of the following controls is not found on a VHF-DSC transceiver? FCC Commercial Element 9 question pool (file headed September 2012), question 2A6, key topic 2: Controls and Functions
  • Which of the following is the best test procedure to isolate the source of distortion in the audio output of a receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 4A6, key topic 4: Receiver Faults-1
  • Which of the following may be adjusted in a FM ratio detector for improved signal-to-noise? FCC Commercial Element 9 question pool (file headed September 2012), question 3A2, key topic 3: Receiver Technology
  • Which of the following procedures may be used in many U.S. ports as a quick field test to determine if a shipboard VHF receiver is operating properly? FCC Commercial Element 9 question pool (file headed September 2012), question 5A3, key topic 5: Receiver Faults-2
  • Which of the following test procedures may be used to determine a VHF receiver’s minimum discernible signal? FCC Commercial Element 9 question pool (file headed September 2012), question 5A2, key topic 5: Receiver Faults-2
  • Which of the following transmitter power levels are permitted by FCC rules? FCC Commercial Element 9 question pool (file headed September 2012), question 2A5, key topic 2: Controls and Functions
  • You attempt to program a new MMSI into a VHF radio with an existing MMSI. The radio will not accept the entry. What is the best course of action to correct this problem? FCC Commercial Element 9 question pool (file headed September 2012), question 9A4, key topic 9: Digital Selective Calling

B: MF-HF-DSC-SITOR (NBDP) Equip. & Operations 71

  • A MF/HF Distress priority DSC call may be formatted to include the following: FCC Commercial Element 9 question pool (file headed September 2012), question 19B5, key topic 19: DSC Operations
  • A received signal on a MF/HF transceiver breaks up rapidly and repeatedly. The signal alternates between mid scale and zero on the “Signal” meter. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 15B6, key topic 15: Receiver Faults-2
  • A ship’s MF-HF whip antenna breaks off and is carried away in a storm. What would you do to regain operation on MF-HF GMDSS frequencies? FCC Commercial Element 9 question pool (file headed September 2012), question 22B5, key topic 22: Antenna Systems
  • The AGC function of an MF/HF receiver is inoperative. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B6, key topic 14: Receiver Faults-1
  • All signals sound normal on an MF/HF receiver except one that has a very high pitched voice barely readable. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B2, key topic 14: Receiver Faults-1
  • An MF-HF transceiver is functioning correctly in voice mode/SSB but not in SITOR (NBDP). What is the most likely source of the problem? FCC Commercial Element 9 question pool (file headed September 2012), question 17B4, key topic 17: Transmitter Faults-1
  • An MF-HF transceiver works properly on voice but not SITOR (NBDP). What is the most likely source of the problem? FCC Commercial Element 9 question pool (file headed September 2012), question 17B1, key topic 17: Transmitter Faults-1
  • How does a noise blanker circuit work in a HF receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 13B6, key topic 13: Receiver Technology
  • How is a J3E signal generated? FCC Commercial Element 9 question pool (file headed September 2012), question 16B1, key topic 16: Transmitter Tech
  • How is the lower sideband eliminated? FCC Commercial Element 9 question pool (file headed September 2012), question 16B3, key topic 16: Transmitter Tech
  • If a vessel is within range of NAVTEX broadcasts and both the Inmarsat-C and the NAVTEX receiver are inoperative the GMDSS operator should: FCC Commercial Element 9 question pool (file headed September 2012), question 21B1, key topic 21: SITOR (NBDP)-FEC
  • If the BFO is turned off what kind of emissions can still be received? FCC Commercial Element 9 question pool (file headed September 2012), question 13B2, key topic 13: Receiver Technology
  • If the vessel is beyond range of NAVTEX broadcasts and the Sat-C system fails, the GMDSS operator must: FCC Commercial Element 9 question pool (file headed September 2012), question 21B5, key topic 21: SITOR (NBDP)-FEC
  • If the vessel is experiencing atmospheric interference with NAVTEX broadcasts, especially in the tropics, the GMDSS operator should: FCC Commercial Element 9 question pool (file headed September 2012), question 21B6, key topic 21: SITOR (NBDP)-FEC
  • If you are listening to another vessel’s HF transmission and it sounds garbled what should you do? FCC Commercial Element 9 question pool (file headed September 2012), question 13B3, key topic 13: Receiver Technology
  • The MF/HF receiver fails to produce any AF output. An ohmmeter reading is near zero between speaker leads. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 15B2, key topic 15: Receiver Faults-2
  • The MF/HF receiver fails to suppress the AF output in the absence of a sufficiently strong input signal. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 15B1, key topic 15: Receiver Faults-2
  • The MF/HF transceiver fails to produce AF output but the radio is powered on and “TX” is illuminated. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 15B5, key topic 15: Receiver Faults-2
  • The MF/HF transceiver produces strong AF output but no signals are heard on any frequency. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 15B3, key topic 15: Receiver Faults-2
  • The phase locked loop circuit in an MF/HF receiver appears to be faulty. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B4, key topic 14: Receiver Faults-1
  • Reducing the “RF Gain” control on an MF/HF transceiver has what effect? FCC Commercial Element 9 question pool (file headed September 2012), question 12B5, key topic 12: Controls, Functions and Displays
  • Selective FEC communications (SFEC) are employed when: FCC Commercial Element 9 question pool (file headed September 2012), question 21B3, key topic 21: SITOR (NBDP)-FEC
  • The sequence ARQ, FEC, SFEC best corresponds to which of the following sequences? FCC Commercial Element 9 question pool (file headed September 2012), question 21B2, key topic 21: SITOR (NBDP)-FEC
  • Using a frequency counter with an accuracy of 2 ppm which of the following are within legal tolerance for the frequencies of 2182.0 kHz and 4125.0 kHz? The counter has a display resolution of 1 Hz. FCC Commercial Element 9 question pool (file headed September 2012), question 11B4, key topic 11: Frequencies and Bandwidth
  • The voice is garbled and unreadable on MF/HF SSB channels. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B1, key topic 14: Receiver Faults-1
  • What are the assigned frequencies for VOICE and SITOR (NBDP) follow on communications? FCC Commercial Element 9 question pool (file headed September 2012), question 11B6, key topic 11: Frequencies and Bandwidth
  • What are the characters that are transmitted to terminate a direct TELEX connection in SITOR (NBDP) operations? FCC Commercial Element 9 question pool (file headed September 2012), question 20B6, key topic 20: SITOR (NBDP)-ARQ
  • What are the major components of a phase locked loop frequency synthesizer? FCC Commercial Element 9 question pool (file headed September 2012), question 16B5, key topic 16: Transmitter Tech
  • What characteristics are desirable in an AGC circuit for SSB voice reception? FCC Commercial Element 9 question pool (file headed September 2012), question 13B4, key topic 13: Receiver Technology
  • What is the allowable frequency tolerance for GMDSS MF-HF transmitters? FCC Commercial Element 9 question pool (file headed September 2012), question 11B3, key topic 11: Frequencies and Bandwidth
  • What is the assigned bandwidth and channel spacing for J2B SITOR (NBDP) transmissions? FCC Commercial Element 9 question pool (file headed September 2012), question 11B2, key topic 11: Frequencies and Bandwidth
  • What is the assigned bandwidth and channel spacing for J3E voice transmissions? FCC Commercial Element 9 question pool (file headed September 2012), question 11B1, key topic 11: Frequencies and Bandwidth
  • What is the correct frequency shift and sub-carrier for MF-HF-DSC? FCC Commercial Element 9 question pool (file headed September 2012), question 19B3, key topic 19: DSC Operations
  • What is the electrical effect of a capacitance in series with the antenna? FCC Commercial Element 9 question pool (file headed September 2012), question 22B3, key topic 22: Antenna Systems
  • What is the electrical effect of an inductance in series with the antenna? FCC Commercial Element 9 question pool (file headed September 2012), question 22B2, key topic 22: Antenna Systems
  • What is the function of an “AGC” button? FCC Commercial Element 9 question pool (file headed September 2012), question 12B6, key topic 12: Controls, Functions and Displays
  • What is the function of the “TUNE” button on a MF/HF transceiver? FCC Commercial Element 9 question pool (file headed September 2012), question 12B2, key topic 12: Controls, Functions and Displays
  • What is the most common method of generating a SITOR (NBDP) signal on shipboard GMDSS equipment? FCC Commercial Element 9 question pool (file headed September 2012), question 16B4, key topic 16: Transmitter Tech
  • What is the primary purpose of both a high and a low I.F. system in a HF receiver? FCC Commercial Element 9 question pool (file headed September 2012), question 13B5, key topic 13: Receiver Technology
  • What is the purpose of a phase comparator in a frequency synthesizer? FCC Commercial Element 9 question pool (file headed September 2012), question 16B6, key topic 16: Transmitter Tech
  • What is the purpose of the antenna tuner? FCC Commercial Element 9 question pool (file headed September 2012), question 22B1, key topic 22: Antenna Systems
  • What is the purpose of the BFO? FCC Commercial Element 9 question pool (file headed September 2012), question 13B1, key topic 13: Receiver Technology
  • What is the purpose of the “ENTER” function. FCC Commercial Element 9 question pool (file headed September 2012), question 12B3, key topic 12: Controls, Functions and Displays
  • What is the purpose of the “R.I.T.“ control on a MF/HF transceiver? FCC Commercial Element 9 question pool (file headed September 2012), question 12B1, key topic 12: Controls, Functions and Displays
  • What is the time diversity reception interval for a MF-HF-DSC call? FCC Commercial Element 9 question pool (file headed September 2012), question 19B4, key topic 19: DSC Operations
  • What mode is a MF/HF transceiver operating in when “TLX” displayed? FCC Commercial Element 9 question pool (file headed September 2012), question 12B4, key topic 12: Controls, Functions and Displays
  • What precedes the phasing signal in a DSC distress alert call? FCC Commercial Element 9 question pool (file headed September 2012), question 19B1, key topic 19: DSC Operations
  • What statement is false concerning DSC calls addressed to MMSI 003669999? FCC Commercial Element 9 question pool (file headed September 2012), question 19B6, key topic 19: DSC Operations
  • What statement is true regarding the exchange between two stations engaged in SITOR (NBDP) communications? FCC Commercial Element 9 question pool (file headed September 2012), question 20B2, key topic 20: SITOR (NBDP)-ARQ
  • What type of code is used for DSC transmissions? FCC Commercial Element 9 question pool (file headed September 2012), question 19B2, key topic 19: DSC Operations
  • What would be the most likely power level to use for initial MF-HF communications? FCC Commercial Element 9 question pool (file headed September 2012), question 16B2, key topic 16: Transmitter Tech
  • Which characters are sent by the ship station to indicate a desire to send a message via a direct connection to a shoreside TELEX subscriber? FCC Commercial Element 9 question pool (file headed September 2012), question 20B5, key topic 20: SITOR (NBDP)-ARQ
  • Which of the following are assigned frequencies for Digital Selective Calling? FCC Commercial Element 9 question pool (file headed September 2012), question 11B5, key topic 11: Frequencies and Bandwidth
  • Which of the following coaxial cables is suitable for use in GMDSS MF/HF antenna systems? FCC Commercial Element 9 question pool (file headed September 2012), question 22B4, key topic 22: Antenna Systems
  • Which of the following conditions could cause very low RF output in a MF/HF transmitter operating in the F1B FEC mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B3, key topic 18: Transmitter Faults-2
  • Which of the following conditions could cause zero RF output in a MF/HF transmitter operating in the F1B FEC mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B5, key topic 18: Transmitter Faults-2
  • Which of the following conditions indicate improper operation of a 150 Watt MF/HF transmitter in the F1B FEC mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B6, key topic 18: Transmitter Faults-2
  • Which of the following conditions indicate the proper operation of a 150 Watt MF/HF transmitter in the F1B ARQ mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B1, key topic 18: Transmitter Faults-2
  • Which of the following conditions indicate the proper operation of a 250 Watt MF/HF transmitter in the F1B FEC mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B2, key topic 18: Transmitter Faults-2
  • Which of the following conditions would be a symptom of malfunction in a 2182 kHz SSB radiotelephone? FCC Commercial Element 9 question pool (file headed September 2012), question 17B5, key topic 17: Transmitter Faults-1
  • Which of the following conditions would indicate the malfunction of a 2182 kHz radiotelephone system? FCC Commercial Element 9 question pool (file headed September 2012), question 17B2, key topic 17: Transmitter Faults-1
  • Which of the following connectors is often used in GMDSS MF/HF antenna systems? FCC Commercial Element 9 question pool (file headed September 2012), question 22B6, key topic 22: Antenna Systems
  • Which of the following is true of SITOR (NBDP) ARQ mode: FCC Commercial Element 9 question pool (file headed September 2012), question 20B3, key topic 20: SITOR (NBDP)-ARQ
  • Which of the following is true of SITOR (NBDP) Mode B (FEC), in the presence of static crashes. FCC Commercial Element 9 question pool (file headed September 2012), question 21B4, key topic 21: SITOR (NBDP)-FEC
  • Which of the following keystrokes or characters follows most commands in ARQ communications when working an automated Coast Station? FCC Commercial Element 9 question pool (file headed September 2012), question 20B4, key topic 20: SITOR (NBDP)-ARQ
  • Which of the following statements concerning SITOR (NBDP) communications is true? FCC Commercial Element 9 question pool (file headed September 2012), question 20B1, key topic 20: SITOR (NBDP)-ARQ
  • which of the following troubleshooting methods is not valid for finding the fault in a MF/HF transmitter operating in the F1B FEC mode? FCC Commercial Element 9 question pool (file headed September 2012), question 18B4, key topic 18: Transmitter Faults-2
  • Which would be an indication of proper operation of a SSB transmitter rated at 60 watt PEP output? FCC Commercial Element 9 question pool (file headed September 2012), question 17B3, key topic 17: Transmitter Faults-1
  • Which would indicate proper operation of a SSB transmitter rated at 60 Watt PEP output in J3E mode? FCC Commercial Element 9 question pool (file headed September 2012), question 17B6, key topic 17: Transmitter Faults-1
  • You are able to hear signals in the SITOR (NBDP) mode but not in the voice/SSB mode. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B5, key topic 14: Receiver Faults-1
  • You are able to hear signals in the voice/SSB mode but not in the SITOR (NBDP) mode. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 14B3, key topic 14: Receiver Faults-1

C: Satellite Systems 59

  • An Inmarsat-C terminal shows a “No Receive Signal” alarm. There is no voltage on the antenna center pin. What is the most likely cause? FCC Commercial Element 9 question pool (file headed September 2012), question 31C1, key topic 31: Equipment Faults and troubleshooting-2
  • An Inmarsat-C terminal will not “LOG IN” and shows an “Antenna not connected” alarm. What action would you take? FCC Commercial Element 9 question pool (file headed September 2012), question 31C3, key topic 31: Equipment Faults and troubleshooting-2
  • An Inmarsat-C terminal will not “LOG IN”. A test antenna cable with a new ADE attached in view of the satellite allows the terminal to “LOG IN”. What steps would you take? FCC Commercial Element 9 question pool (file headed September 2012), question 31C2, key topic 31: Equipment Faults and troubleshooting-2
  • The antenna creeps up and down after initialization. What action would you take? FCC Commercial Element 9 question pool (file headed September 2012), question 31C5, key topic 31: Equipment Faults and troubleshooting-2
  • The antenna goes past the AZ EL of the satellite but does not initialize but you can manually point the antenna at the satellite and acquire signal. What is the most likely problem? FCC Commercial Element 9 question pool (file headed September 2012), question 31C4, key topic 31: Equipment Faults and troubleshooting-2
  • The antenna tries to initialize then points straight up and stops. What is the most likely problem? FCC Commercial Element 9 question pool (file headed September 2012), question 31C6, key topic 31: Equipment Faults and troubleshooting-2
  • How can a LES/RCC (Rescue Coordination Centre) determine if an Inmarsat-C Distress Alert is a TEST transmission? FCC Commercial Element 9 question pool (file headed September 2012), question 30C2, key topic 30: Equipment Faults and troubleshooting-1
  • How do you perform a LOOP BACK test? FCC Commercial Element 9 question pool (file headed September 2012), question 24C2, key topic 24: C-Terminals
  • How is the GPS usually interconnected with other bridge equipment? FCC Commercial Element 9 question pool (file headed September 2012), question 28C3, key topic 28: GPS
  • How many NCS’s operate in each Inmarsat ocean region per Inmarsat system? FCC Commercial Element 9 question pool (file headed September 2012), question 24C5, key topic 24: C-Terminals
  • Interference induced from nearby HF transmitters may cause Inmarsat system failures. What is the most appropriate action to resolve this problem? FCC Commercial Element 9 question pool (file headed September 2012), question 32C5, key topic 32: Equipment Faults and troubleshooting-3
  • LRIT Long Range Information Tracking data: FCC Commercial Element 9 question pool (file headed September 2012), question 25C2, key topic 25: Long Range Identity Tracking
  • LRIT Long Range Information Tracking: FCC Commercial Element 9 question pool (file headed September 2012), question 25C3, key topic 25: Long Range Identity Tracking
  • The U.S. National Data Center that monitors polling input for each US Flag ship: FCC Commercial Element 9 question pool (file headed September 2012), question 25C1, key topic 25: Long Range Identity Tracking
  • What action should be taken if an Inmarsat Fleet Broadband antenna continuously changes azimuth after initialization? FCC Commercial Element 9 question pool (file headed September 2012), question 32C1, key topic 32: Equipment Faults and troubleshooting-3
  • What components does an Inmarsat Fleet Broadband RADOME typically include? FCC Commercial Element 9 question pool (file headed September 2012), question 29C6, key topic 29: Antenna Systems
  • What condition can indicate a communication failure between the second receiver (RX2) and the Antenna Control Unit (ACU) in an Inmarsat Fleet 77 terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 30C4, key topic 30: Equipment Faults and troubleshooting-1
  • What condition will lower the observed bit rate on a Fleet Broadband terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 32C6, key topic 32: Equipment Faults and troubleshooting-3
  • What condition would cause a connection failure between a technician’s laptop and an Inmarsat Fleet Broadband terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 32C4, key topic 32: Equipment Faults and troubleshooting-3
  • What condition would cause an IP connection failure between a technician’s laptop and an Inmarsat Fleet Broadband terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 32C3, key topic 32: Equipment Faults and troubleshooting-3
  • What condition would cause failure of an Inmarsat-C terminal to power up when AC voltage is present at the input terminals of the power supply? FCC Commercial Element 9 question pool (file headed September 2012), question 32C2, key topic 32: Equipment Faults and troubleshooting-3
  • What do EGC messages contain? FCC Commercial Element 9 question pool (file headed September 2012), question 24C3, key topic 24: C-Terminals
  • What error message may be displayed if a connection to the Inmarsat Mobile Packet Data Service (MPDS) network fails? FCC Commercial Element 9 question pool (file headed September 2012), question 30C6, key topic 30: Equipment Faults and troubleshooting-1
  • What function does the LNA perform? FCC Commercial Element 9 question pool (file headed September 2012), question 23C3, key topic 23: Technology
  • What is a best practice for installing Inmarsat satellite antennas aboard ship? FCC Commercial Element 9 question pool (file headed September 2012), question 29C5, key topic 29: Antenna Systems
  • What is an LNA? FCC Commercial Element 9 question pool (file headed September 2012), question 23C2, key topic 23: Technology
  • What is signal to noise ratio? FCC Commercial Element 9 question pool (file headed September 2012), question 23C5, key topic 23: Technology
  • What is the abbreviation for signal to noise? FCC Commercial Element 9 question pool (file headed September 2012), question 23C6, key topic 23: Technology
  • What is the configuration for Thrane & Thrane F250 & F500 facsimile operation? FCC Commercial Element 9 question pool (file headed September 2012), question 27C4, key topic 27: Fleet Broadband Terminals
  • What is the configuration Thrane & Thrane F500 for standard voice telephone operation? FCC Commercial Element 9 question pool (file headed September 2012), question 27C5, key topic 27: Fleet Broadband Terminals
  • What is the fade margin factor? FCC Commercial Element 9 question pool (file headed September 2012), question 23C4, key topic 23: Technology
  • What is the meaning of the “ACB” Inmarsat-C Non-Delivery Notification (NDN) failure code? FCC Commercial Element 9 question pool (file headed September 2012), question 30C3, key topic 30: Equipment Faults and troubleshooting-1
  • What is the minimum number of satellites that must be received to provide the highest accuracy? FCC Commercial Element 9 question pool (file headed September 2012), question 28C6, key topic 28: GPS
  • What is the purpose of the Differential GPS system and how does it work? FCC Commercial Element 9 question pool (file headed September 2012), question 28C2, key topic 28: GPS
  • What is the usual arrangement of GPS satellites? FCC Commercial Element 9 question pool (file headed September 2012), question 28C1, key topic 28: GPS
  • What must a LRIT terminal do? FCC Commercial Element 9 question pool (file headed September 2012), question 25C5, key topic 25: Long Range Identity Tracking
  • What protocol can be used in connecting a PC to the LAN interface of an Inmarsat terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 27C1, key topic 27: Fleet Broadband Terminals
  • What satellite system does not support LRIT? FCC Commercial Element 9 question pool (file headed September 2012), question 25C6, key topic 25: Long Range Identity Tracking
  • What type of services cannot be provided by the Inmarsat-C system? FCC Commercial Element 9 question pool (file headed September 2012), question 24C6, key topic 24: C-Terminals
  • When a compulsory equipped IMO ship is not correctly broadcasting LRIT Info what action should be taken? FCC Commercial Element 9 question pool (file headed September 2012), question 25C4, key topic 25: Long Range Identity Tracking
  • When is a PIN Unlock Key (PUK) used with an Inmarsat terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 27C2, key topic 27: Fleet Broadband Terminals
  • Which of the following actions should be taken to minimize shock hazard of an Inmarsat terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 24C1, key topic 24: C-Terminals
  • Which of the following best describes a phased array antenna system? FCC Commercial Element 9 question pool (file headed September 2012), question 29C3, key topic 29: Antenna Systems
  • Which of the following best describes a Subscriber Identity Module (SIM)? FCC Commercial Element 9 question pool (file headed September 2012), question 27C6, key topic 27: Fleet Broadband Terminals
  • Which of the following best describes Inmarsat BGAN Streaming Data service? FCC Commercial Element 9 question pool (file headed September 2012), question 26C3, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following best describes the GPS satellite signals transmitted? FCC Commercial Element 9 question pool (file headed September 2012), question 28C5, key topic 28: GPS
  • Which of the following best describes the polarization of a satellite signal? FCC Commercial Element 9 question pool (file headed September 2012), question 29C1, key topic 29: Antenna Systems
  • Which of the following conditions would prevent communications between an Inmarsat-C data port and external data terminal equipment (DTE)? FCC Commercial Element 9 question pool (file headed September 2012), question 30C1, key topic 30: Equipment Faults and troubleshooting-1
  • Which of the following devices can cause interference to Fleet 77/55 systems? FCC Commercial Element 9 question pool (file headed September 2012), question 30C5, key topic 30: Equipment Faults and troubleshooting-1
  • Which of the following Inmarsat units stores configuration data and contains all user interfaces and LED indicators? FCC Commercial Element 9 question pool (file headed September 2012), question 26C1, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following is characteristic of an Inmarsat-C antenna? FCC Commercial Element 9 question pool (file headed September 2012), question 29C4, key topic 29: Antenna Systems
  • Which of the following is characteristic of the parabolic dish antenna? FCC Commercial Element 9 question pool (file headed September 2012), question 29C2, key topic 29: Antenna Systems
  • Which of the following is not a characteristic of an Inmarsat Fleet Broadband IP handset? FCC Commercial Element 9 question pool (file headed September 2012), question 26C6, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following is not a function of an Inmarsat Fleet Broadband IP handset? FCC Commercial Element 9 question pool (file headed September 2012), question 26C2, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following is NOT a function of the LAN port on a Fleet Broadband terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 27C3, key topic 27: Fleet Broadband Terminals
  • Which of the following is not recommended for Inmarsat-C antenna installations? FCC Commercial Element 9 question pool (file headed September 2012), question 24C4, key topic 24: C-Terminals
  • Which of the following is the best procedure to test the Inmarsat Distress Alarm? FCC Commercial Element 9 question pool (file headed September 2012), question 26C4, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following is the correct Fax/Data configuration of a Fleet Broadband terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 26C5, key topic 26: Fleet-33-55-77 Terminals
  • Which of the following statements is true? FCC Commercial Element 9 question pool (file headed September 2012), question 28C4, key topic 28: GPS

D: Other GMDSS Equipment 24

  • At what interval must the SART’s battery be replaced? FCC Commercial Element 9 question pool (file headed September 2012), question 34D4, key topic 34: SART
  • Equipment for radiotelephony use in survival craft stations under GMDSS must have what capability? FCC Commercial Element 9 question pool (file headed September 2012), question 35D4, key topic 35: Survival Craft Transceiver
  • Equipment for radiotelephony use in survival craft stations under GMDSS must have what characteristics? FCC Commercial Element 9 question pool (file headed September 2012), question 35D6, key topic 35: Survival Craft Transceiver
  • How can reception of certain NAVTEX broadcasts be prevented? FCC Commercial Element 9 question pool (file headed September 2012), question 36D4, key topic 36: Navtex
  • How is a NAVTEX receiver programmed to reject certain messages? FCC Commercial Element 9 question pool (file headed September 2012), question 36D3, key topic 36: Navtex
  • How is accuracy insured in NAVTEX broadcasts? FCC Commercial Element 9 question pool (file headed September 2012), question 36D5, key topic 36: Navtex
  • How often must the automatic release mechanism be replaced. FCC Commercial Element 9 question pool (file headed September 2012), question 33D5, key topic 33: EPIRB
  • How often must the EPIRB battery be replaced? FCC Commercial Element 9 question pool (file headed September 2012), question 33D3, key topic 33: EPIRB
  • How often must the Survival Craft Transceiver battery be changed? FCC Commercial Element 9 question pool (file headed September 2012), question 35D1, key topic 35: Survival Craft Transceiver
  • How should the signal from a Search And Rescue RADAR Transponder appear on a RADAR display? FCC Commercial Element 9 question pool (file headed September 2012), question 34D1, key topic 34: SART
  • In what frequency band does a search and rescue transponder operate? FCC Commercial Element 9 question pool (file headed September 2012), question 34D2, key topic 34: SART
  • NAVTEX broadcasts are sent: FCC Commercial Element 9 question pool (file headed September 2012), question 36D6, key topic 36: Navtex
  • The NAVTEX is powering on and appears to be functioning normally except there have been no new messages for an extended period. The station settings are correct. What is the most likely source of the problem? FCC Commercial Element 9 question pool (file headed September 2012), question 36D2, key topic 36: Navtex
  • What are the characteristics of the SART transmitted signal? FCC Commercial Element 9 question pool (file headed September 2012), question 34D5, key topic 34: SART
  • What causes the SART to begin a transmission? FCC Commercial Element 9 question pool (file headed September 2012), question 34D3, key topic 34: SART
  • What feature is not a component of a 406 MHz satellite EPIRB? FCC Commercial Element 9 question pool (file headed September 2012), question 33D4, key topic 33: EPIRB
  • What is the approximate distance between dots on a radar display at a distance of 5 miles? FCC Commercial Element 9 question pool (file headed September 2012), question 34D6, key topic 34: SART
  • What is the minimum receiver sensitivity required for a Survival Craft Transceiver? FCC Commercial Element 9 question pool (file headed September 2012), question 35D2, key topic 35: Survival Craft Transceiver
  • What is the minimum required effective radiated power? FCC Commercial Element 9 question pool (file headed September 2012), question 35D3, key topic 35: Survival Craft Transceiver
  • What is the purpose of the magnet in the EPIRB mounting bracket? FCC Commercial Element 9 question pool (file headed September 2012), question 33D2, key topic 33: EPIRB
  • Which is not a function of a satellite under COSPAS-SARSAT using satellite EPIRBs? FCC Commercial Element 9 question pool (file headed September 2012), question 33D1, key topic 33: EPIRB
  • Which of the following is normally part of 406 MHz satellite EPIRBs? FCC Commercial Element 9 question pool (file headed September 2012), question 33D6, key topic 33: EPIRB
  • Which of the following is the primary frequency that is used exclusively for NAVTEX broadcasts internationally? FCC Commercial Element 9 question pool (file headed September 2012), question 36D1, key topic 36: Navtex
  • Which statement is NOT true regarding the requirements of survival craft portable two-way VHF radiotelephone equipment? FCC Commercial Element 9 question pool (file headed September 2012), question 35D5, key topic 35: Survival Craft Transceiver

E: Power Sources 24

  • A fully automatic GMDSS compliant Battery charger/ Power supply’s high (Full) charging mode must be disabled during setup for what type batteries? FCC Commercial Element 9 question pool (file headed September 2012), question 38E6, key topic 38: Battery Chargers and Power Sources
  • How often should high charging be use with a standard lead acid battery and a fully automatic GMDSS compliant Battery charger? FCC Commercial Element 9 question pool (file headed September 2012), question 38E1, key topic 38: Battery Chargers and Power Sources
  • Power supplies with capacitive input filters have the following characteristics: FCC Commercial Element 9 question pool (file headed September 2012), question 39E6, key topic 39: Power Supplies-1
  • Power supplies with inductive input filters have the following characteristics: FCC Commercial Element 9 question pool (file headed September 2012), question 39E5, key topic 39: Power Supplies-1
  • What are the different modes of charging for a GMDSS compliant battery charger/supply? FCC Commercial Element 9 question pool (file headed September 2012), question 38E2, key topic 38: Battery Chargers and Power Sources
  • What are the disadvantages of using a switcher type power supply? FCC Commercial Element 9 question pool (file headed September 2012), question 39E4, key topic 39: Power Supplies-1
  • What are the input/output voltages of a “BUCK” switching power supply with a 50% duty cycle? FCC Commercial Element 9 question pool (file headed September 2012), question 40E5, key topic 40: Power Supplies-2
  • What are the main advantages of using switcher type power supply? FCC Commercial Element 9 question pool (file headed September 2012), question 39E3, key topic 39: Power Supplies-1
  • What is a gel cell battery and how is it maintained & cared for? FCC Commercial Element 9 question pool (file headed September 2012), question 37E5, key topic 37: Batteries
  • What is the configuration for a mains operated switching power supply with output regulation? FCC Commercial Element 9 question pool (file headed September 2012), question 40E3, key topic 40: Power Supplies-2
  • What is the effect of temperature on the specific gravity of lead acid batteries? FCC Commercial Element 9 question pool (file headed September 2012), question 37E2, key topic 37: Batteries
  • What is the function of a crowbar circuit? FCC Commercial Element 9 question pool (file headed September 2012), question 40E1, key topic 40: Power Supplies-2
  • What is the meaning of “Reserve Source of Energy”? FCC Commercial Element 9 question pool (file headed September 2012), question 38E4, key topic 38: Battery Chargers and Power Sources
  • What is the normal specific gravity of a fully charged lead acid battery cell? What device is used to measuring the electrolyte of a lead acid battery? FCC Commercial Element 9 question pool (file headed September 2012), question 37E4, key topic 37: Batteries
  • What is the normal voltage of a single lead acid battery cell? FCC Commercial Element 9 question pool (file headed September 2012), question 37E6, key topic 37: Batteries
  • What is the normal voltage of a single NICAD battery cell? FCC Commercial Element 9 question pool (file headed September 2012), question 37E1, key topic 37: Batteries
  • What will cause an individual battery cell to reverse polarity? FCC Commercial Element 9 question pool (file headed September 2012), question 37E3, key topic 37: Batteries
  • What would be an indication of a malfunction on a GMDSS station with a 24 VDC battery system? FCC Commercial Element 9 question pool (file headed September 2012), question 38E3, key topic 38: Battery Chargers and Power Sources
  • Which of the following best describes a standard full wave rectifier power supply? FCC Commercial Element 9 question pool (file headed September 2012), question 39E1, key topic 39: Power Supplies-1
  • Which of the following is not one of the main advantages of a switching power supply? FCC Commercial Element 9 question pool (file headed September 2012), question 40E2, key topic 40: Power Supplies-2
  • Which of the following statements about a switching mode power supply input current is correct? FCC Commercial Element 9 question pool (file headed September 2012), question 40E6, key topic 40: Power Supplies-2
  • Which of the following statements about switching power supplies is the most accurate? FCC Commercial Element 9 question pool (file headed September 2012), question 40E4, key topic 40: Power Supplies-2
  • Which of the following statements concerning power supply filters is true? FCC Commercial Element 9 question pool (file headed September 2012), question 39E2, key topic 39: Power Supplies-1
  • With a fully automatic GMDSS compliant battery charger / power supply, when must the high charging process be interrupted? FCC Commercial Element 9 question pool (file headed September 2012), question 38E5, key topic 38: Battery Chargers and Power Sources

F: Other Equipment and Networks 36

  • 10Base-T and 100Base-TX systems generally uses the following type of cable: FCC Commercial Element 9 question pool (file headed September 2012), question 42F3, key topic 42: Computer Networks – Ethernet
  • A typical PC program that is used widely for logging and troubleshooting NMEA 0183 data is: FCC Commercial Element 9 question pool (file headed September 2012), question 43F1, key topic 43: Local Area Networks- NMEA-0183
  • AIS units use the following: FCC Commercial Element 9 question pool (file headed September 2012), question 45F6, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • An important difference between NMEA 0183 and NMEA 2000 is: FCC Commercial Element 9 question pool (file headed September 2012), question 43F6, key topic 43: Local Area Networks- NMEA-0183
  • The current and most recent version of NMEA 0183 uses what standard for data communications? FCC Commercial Element 9 question pool (file headed September 2012), question 43F3, key topic 43: Local Area Networks- NMEA-0183
  • How do you determine the type of disc drives in an XP system? FCC Commercial Element 9 question pool (file headed September 2012), question 41F5, key topic 41: Computers
  • How does the Ship Security Alert System operate? FCC Commercial Element 9 question pool (file headed September 2012), question 45F5, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • In an Ethernet network, the available bandwidth is shared between all nodes within the same: FCC Commercial Element 9 question pool (file headed September 2012), question 42F6, key topic 42: Computer Networks – Ethernet
  • The NMEA 2000 backbone operating speed is: FCC Commercial Element 9 question pool (file headed September 2012), question 44F4, key topic 44: Local Area Networks- NMEA-2000
  • NMEA 2000 Certified Device identify their current requirements in terms of LENs (load Equivalent Number). 1 LEN is equal to: FCC Commercial Element 9 question pool (file headed September 2012), question 44F2, key topic 44: Local Area Networks- NMEA-2000
  • Nodes in an Ethernet network are interconnected using a cable making a “Home Run“back to the central: FCC Commercial Element 9 question pool (file headed September 2012), question 42F1, key topic 42: Computer Networks – Ethernet
  • Power is on but the computer will not boot into the operating system. What steps should you take? FCC Commercial Element 9 question pool (file headed September 2012), question 41F4, key topic 41: Computers
  • The printer will not print a document. Which of the following is NOT a likely reason? FCC Commercial Element 9 question pool (file headed September 2012), question 41F1, key topic 41: Computers
  • There is no display on the monitor. What are the most likely causes? FCC Commercial Element 9 question pool (file headed September 2012), question 41F2, key topic 41: Computers
  • The Voltage of the NMEA 2000 backbone power supply pair must be maintained to within the following range. FCC Commercial Element 9 question pool (file headed September 2012), question 44F1, key topic 44: Local Area Networks- NMEA-2000
  • What are important considerations when replacing a CD-ROM drive? FCC Commercial Element 9 question pool (file headed September 2012), question 41F6, key topic 41: Computers
  • What are the four main functions of the “BIOS” in most computers? FCC Commercial Element 9 question pool (file headed September 2012), question 41F3, key topic 41: Computers
  • What are the most commonly used IP addresses for routers? FCC Commercial Element 9 question pool (file headed September 2012), question 42F5, key topic 42: Computer Networks – Ethernet
  • What are the principles of operation of a fiber-optic gyro compass? FCC Commercial Element 9 question pool (file headed September 2012), question 45F4, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • What initial steps should be taken when installing a router? FCC Commercial Element 9 question pool (file headed September 2012), question 42F4, key topic 42: Computer Networks – Ethernet
  • What inputs are normally required for an Auto Pilot? FCC Commercial Element 9 question pool (file headed September 2012), question 46F4, key topic 46: ECDIS – Auto Pilots – Data Recorders
  • What is a common range of frequencies used for depth finding equipment? FCC Commercial Element 9 question pool (file headed September 2012), question 45F1, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • What is a common range of pulse widths used for depth finding equipment? FCC Commercial Element 9 question pool (file headed September 2012), question 45F2, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • What is the maximum length for a drop cable to a single NMEA 2000 device? FCC Commercial Element 9 question pool (file headed September 2012), question 44F6, key topic 44: Local Area Networks- NMEA-2000
  • What is the maximum length of a USB 2.0 cable between two hubs or between a hub and peripheral? FCC Commercial Element 9 question pool (file headed September 2012), question 42F2, key topic 42: Computer Networks – Ethernet
  • what is the maximum signal voltage range that an NMEA-0183 unit must be capable of handling without damage? FCC Commercial Element 9 question pool (file headed September 2012), question 43F2, key topic 43: Local Area Networks- NMEA-0183
  • What is the purpose of the “carbon pile” on an older gyro compass? FCC Commercial Element 9 question pool (file headed September 2012), question 45F3, key topic 45: Depth Finders, Gyro Compass, SSAS, AIS
  • What procedure must be followed before using C-Map charts for an Electronic Chart System? FCC Commercial Element 9 question pool (file headed September 2012), question 46F1, key topic 46: ECDIS – Auto Pilots – Data Recorders
  • What type of data communication is used for NMEA 0183. FCC Commercial Element 9 question pool (file headed September 2012), question 43F4, key topic 43: Local Area Networks- NMEA-0183
  • When viewing NMEA 2000 data you must use the following. FCC Commercial Element 9 question pool (file headed September 2012), question 44F5, key topic 44: Local Area Networks- NMEA-2000
  • Which of the following are NOT components of a NMEA 2000 network? FCC Commercial Element 9 question pool (file headed September 2012), question 44F3, key topic 44: Local Area Networks- NMEA-2000
  • Which of the following is a necessary component of an auto pilot? FCC Commercial Element 9 question pool (file headed September 2012), question 46F3, key topic 46: ECDIS – Auto Pilots – Data Recorders
  • Which of the following is not an accurate list of functions/data recorded by the Vessel Data Recorder? FCC Commercial Element 9 question pool (file headed September 2012), question 46F5, key topic 46: ECDIS – Auto Pilots – Data Recorders
  • Which of the following lists of data inputs for an Electronic Chart System is incorrect? FCC Commercial Element 9 question pool (file headed September 2012), question 46F2, key topic 46: ECDIS – Auto Pilots – Data Recorders
  • Which of the following statements about an NMEA -0183 system is correct? FCC Commercial Element 9 question pool (file headed September 2012), question 43F5, key topic 43: Local Area Networks- NMEA-0183
  • Which of the following statements about Vessel Data Recorders is NOT true? FCC Commercial Element 9 question pool (file headed September 2012), question 46F6, key topic 46: ECDIS – Auto Pilots – Data Recorders

G: Inspections, Installations and Instruments 24

  • A 4 digit multi-meter with an accuracy of 0.15% and 2 counts is set on the 6 volt scale. What range of readings may be expected when measuring a 5 volt DC source? FCC Commercial Element 9 question pool (file headed September 2012), question 49G1, key topic 49: Test Equipment-1
  • A 4 digit multi-meter with an accuracy of 0.15% and 2 counts is set on the 60 volt scale. What range of readings may be expected when measuring a 24 volt DC source? FCC Commercial Element 9 question pool (file headed September 2012), question 49G2, key topic 49: Test Equipment-1
  • A good lab type signal generator for VHF measurements should be able to reduce its output to: FCC Commercial Element 9 question pool (file headed September 2012), question 49G4, key topic 49: Test Equipment-1
  • a SINAD meter consists of a multi-range audio frequency voltmeter: FCC Commercial Element 9 question pool (file headed September 2012), question 50G2, key topic 50: Test Equipment-2
  • After the station has successfully passed the survey what document is issued to the vessel? FCC Commercial Element 9 question pool (file headed September 2012), question 48G5, key topic 48: Annual Inspections
  • An analog RF wattmeter provides the most accurate reading: FCC Commercial Element 9 question pool (file headed September 2012), question 50G4, key topic 50: Test Equipment-2
  • Bridge equipment separation recommendations generally refer to what instrument? FCC Commercial Element 9 question pool (file headed September 2012), question 47G4, key topic 47: Equipment Installation
  • The characteristics of a 10:1 attenuation probe for an oscilloscope is as follows: FCC Commercial Element 9 question pool (file headed September 2012), question 49G5, key topic 49: Test Equipment-1
  • In dual-trace oscilloscopes the purpose of the “Mode” control is to: FCC Commercial Element 9 question pool (file headed September 2012), question 49G6, key topic 49: Test Equipment-1
  • What action must be taken after an Inmarsat-C system is fully installed? FCC Commercial Element 9 question pool (file headed September 2012), question 47G6, key topic 47: Equipment Installation
  • What are the operator’s license requirements for conducting a GMDSS ship station annual inspection? FCC Commercial Element 9 question pool (file headed September 2012), question 48G1, key topic 48: Annual Inspections
  • What battery tests are made during the annual inspection? FCC Commercial Element 9 question pool (file headed September 2012), question 48G3, key topic 48: Annual Inspections
  • What is the best method for grounding an Inmarsat-C terminal? FCC Commercial Element 9 question pool (file headed September 2012), question 47G1, key topic 47: Equipment Installation
  • What is the easiest way to test the Inmarsat-C terminal for proper operation? FCC Commercial Element 9 question pool (file headed September 2012), question 48G4, key topic 48: Annual Inspections
  • What is the most important consideration for installing a Full-Duplex VHF radiotelephone. FCC Commercial Element 9 question pool (file headed September 2012), question 47G2, key topic 47: Equipment Installation
  • What is the most important factor when locating depth finder transducers? FCC Commercial Element 9 question pool (file headed September 2012), question 47G3, key topic 47: Equipment Installation
  • What is the most important specification for an R. F. Signal Generator used at VHF frequencies? FCC Commercial Element 9 question pool (file headed September 2012), question 49G3, key topic 49: Test Equipment-1
  • What is the purpose of a deviation meter? FCC Commercial Element 9 question pool (file headed September 2012), question 50G5, key topic 50: Test Equipment-2
  • What log entries are required after passing the annual inspection? FCC Commercial Element 9 question pool (file headed September 2012), question 48G2, key topic 48: Annual Inspections
  • What type of signals are usually provided by a simple Function Generator? FCC Commercial Element 9 question pool (file headed September 2012), question 50G1, key topic 50: Test Equipment-2
  • What would be the most likely reason to observe the transmitter output with a spectrum analyzer? FCC Commercial Element 9 question pool (file headed September 2012), question 50G6, key topic 50: Test Equipment-2
  • When installing an Inmarsat-C antenna what should be the minimum distance to other Inmarsat antennas? FCC Commercial Element 9 question pool (file headed September 2012), question 47G5, key topic 47: Equipment Installation
  • Which of the following is NOT a required VHF test during an annual inspection? FCC Commercial Element 9 question pool (file headed September 2012), question 48G6, key topic 48: Annual Inspections
  • Which of the following statements about a logic probe is false? FCC Commercial Element 9 question pool (file headed September 2012), question 50G3, key topic 50: Test Equipment-2

How this list was compiled: Questions, answer choices and keyed answers are from the FCC Commercial Element 9 Question Pool (the file is headed "FCC – Element-9 GMDSS Maintainer License: September 2012"; 300 questions, 7 sections, 50 key topics), the file the FCC links from its commercial operator examinations page as Element 9: https://www.fcc.gov/sites/default/files/Element%209_0.pdf . fcc.gov could not be opened on 2026-10-02, so the file was read from the Internet Archive capture of that address dated 2026-03-20 (https://web.archive.org/web/20260320154351/https://www.fcc.gov/sites/default/files/Element%209_0.pdf); the file was made on December 5, 2016. The examinations page (https://www.fcc.gov/wireless/bureau-divisions/mobility-division/commercial-radio-operator-license-program/examinations, page dated by the FCC March 6, 2024) was read from the capture dated 2026-02-10 (https://web.archive.org/web/20260210033816/https://www.fcc.gov/wireless/bureau-divisions/mobility-division/commercial-radio-operator-license-program/examinations): it lists this file as the Element 9 pool and gives the exam as at least 38 out of 50 questions. License and element requirements were read in 47 CFR 13.201, 13.203, 13.207 and 13.215 at https://www.law.cornell.edu/cfr/text/47/13.201 and the pages beside it on 2026-10-02. Checked 2026-10-02. Licence: The questions, choices and keyed answers are the published FCC question pool, which the FCC releases to the public so that candidates can study it (47 CFR 13.215). The pool file carries no copyright or reuse statement. The explanations are own work, written for this site. Nothing is taken from a prep company, a study guide or another practice test.

How it works

This unofficial FCC Element 9 study guide is the published pool itself, 297 of its 300 questions, for the GMDSS Radio Maintainer's License. That license adds Element 1 and Element 3. Exam mode draws 50 questions and needs 38 right.

Read the full guide

A GMDSS maintainer study guide in seven sections

47 CFR 13.203 ties Element 9 to the IMO radio maintenance guidelines for sea areas A3 and A4. Fifty key topics of six questions: VHF-DSC equipment has 10 key topics, MF-HF-DSC and SITOR 12, satellite systems 10, other GMDSS equipment 4, power sources 4, other equipment and networks 6, and inspections, installations and instruments 4. Start from, under the question, picks a section.

What this bank changes

Choices are shuffled. Two questions are held back because each repeats an earlier question's text, and one because the pool file prints the same answer under two letters.

  • Many key topics are fault-finding: a symptom is given and the keyed answer names the stage or part that fits it.

Questions and answers

Which exams does the GMDSS Radio Maintainer's License take?

Three written elements: 1, 3 and 9, under 47 CFR 13.201(b)(6). Element 1 is radio law and operating practice, Element 3 is electronics, and Element 9, on this page, is GMDSS maintenance.

How many questions are on Element 9, and how many can you miss?

Fifty, and 12 may be wrong. The FCC's examinations page puts the pass mark at 38 of 50 and names no time limit.

Are these the questions on the real Element 9 exam?

Under 47 CFR 13.207(b) an examiner builds each question set from the published pool, and this bank is that pool less three questions. It was read from the FCC's file as archived in March 2026.

Is Element 9 the same as Element 7?

No. Element 7 is the operating exam for the GMDSS Radio Operator's License. Element 9 asks about repair: receiver and transmitter faults, antennas, power supplies, networks and the annual station inspection.

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