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2013 Element 9 pool
292 / 300 questions need explanations
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What is the minimum receiver sensitivity required for a Survival Craft Transceiver?
  • 0.1 microvolts (25% chose this)
  • 0.5 microvolts (20% chose this)
  • 1.0 microvolts (33% chose this)
  • 2.0 microvolts (22% chose this)
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Which of the following is characteristic of an Inmarsat-C antenna?
  • The antenna is RHC polarized with a cardioid radiation pattern. (12% chose this)
  • The antenna is vertically polarized and highly directional. (25% chose this)
  • The antenna is horizontally polarized and omni-directional. (38% chose this)
  • The antenna is RHC polarized with an omni-directional radiation pattern. (25% chose this)
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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?
  • The second I.F. amplifier has become defective. (14% chose this)
  • The voltage controlled oscillator is defective. (14% chose this)
  • The 2.8 kHz filter has become defective. (44% chose this)
  • The 1615 kHz audio oscillator is not working. (28% chose this)
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What is the most common type of emission for shipboard VHF-DSC transceivers?
  • F1B (24% chose this)
  • J3B (27% chose this)
  • G3E (25% chose this)
  • H3E (24% chose this)
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Which of the following statements about Vessel Data Recorders is NOT true?
  • The "Crash Survivable Module" (CSM) retains data for up to 12 hours. (29% chose this)
  • The "Data Acquisition Unit" (DAU) may have data storage for as long as 30 days. (18% chose this)
  • Data input may include Rudder feedback, Depth of water and Radar. (22% chose this)
  • Data input may include Position, Date, MSI information and Audio from the bridge. (31% chose this)
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What is the most important specification for an R. F. Signal Generator used at VHF frequencies?
  • Frequency accuracy (43% chose this)
  • Modulation percentage (6% chose this)
  • Low signal leakage (30% chose this)
  • Frequency modulation (22% chose this)
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What are the assigned frequencies for VOICE and SITOR (NBDP) follow on communications?
  • VOICE: 2182 kHz, 4125 kHz, 6312 kHz, SITOR (NBDP) 4177.5 kHz, 8376.5 kHz, 12520 kHz (42% chose this)
  • VOICE: 8291 kHz, 12577 kHz, 16420 kHz, SITOR (NBDP) 4125 kHz, 6268 kHz, 8376.5 kHz (8% chose this)
  • VOICE: 4125 kHz, 8291 kHz, 16420 kHz, SITOR (NBDP) 2174.5 kHz, 6268 kHz, 12520 kHz (34% chose this)
  • VOICE: 6215 kHz, 8414.5 kHz, 12290 kHz, SITOR (NBDP) 6268 kHz, 8291 kHz, 12520 kHz (16% chose this)
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What is the minimum required effective radiated power?
  • 0.25 watt (30% chose this)
  • 0.5 watt (11% chose this)
  • 1 watt (54% chose this)
  • 2 watts (5% chose this)
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What is the purpose of a phase comparator in a frequency synthesizer?
  • Compare the divided outputs of the master oscillator and the voltage controlled oscillator. (35% chose this)
  • Compare the direct outputs of the master oscillator and the voltage controlled oscillator. (31% chose this)
  • Compare the direct output of the master oscillator and the divided output of the voltage controlled oscillator. (18% chose this)
  • Compare the divided output of the master oscillator and the direct output of the voltage controlled oscillator. (16% chose this)
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What is a common range of pulse widths used for depth finding equipment?
  • 10 to 30 microseconds (14% chose this)
  • 25 to 600 microseconds (36% chose this)
  • 2 to 20 milliseconds (18% chose this)
  • 50 to 200 milliseconds (32% chose this)
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The NMEA 2000 backbone operating speed is:
  • 250 bps (36% chose this)
  • 500 bps (13% chose this)
  • 1500 bps (23% chose this)
  • 2000 bps (28% chose this)
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What is the meaning of the "ACB" Inmarsat-C Non-Delivery Notification (NDN) failure code?
  • The terminal received an invalid answer-back from the destination. (27% chose this)
  • Access to the Inmarsat system has been barred. (37% chose this)
  • The Automatic Communications Bit error rate was exceeded. (25% chose this)
  • An Inmarsat message channel failure occurred. (12% chose this)
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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?
  • The RF power applied to the input of the Power Amplifier (PA) stage is excessive. (16% chose this)
  • There is an open connection between the radio's PA stage and the antenna connector. (40% chose this)
  • The bias voltage applied to the Power Amplifier (PA) stage may be insufficient. (38% chose this)
  • A defective capacitor is blocking DC voltage from appearing at the antenna connector. (6% chose this)
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What is the time diversity reception interval for a MF-HF-DSC call?
  • 33-1/3 milliseconds (39% chose this)
  • 400 milliseconds (34% chose this)
  • 450 milliseconds (11% chose this)
  • 250 milliseconds (16% chose this)
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After the station has successfully passed the survey what document is issued to the vessel?
  • FCC 817 (16% chose this)
  • SOLAS Annual Certificate (33% chose this)
  • Radio Station License (16% chose this)
  • Cargo Ship Safety Certificate (35% chose this)
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Power supplies with capacitive input filters have the following characteristics:
  • Relatively high output voltage with low rectifier peak currents. (13% chose this)
  • High transformer utilization factor with good voltage regulation. (6% chose this)
  • Poor voltage regulation and high rectifier peak currents. (38% chose this)
  • Good voltage regulation with high transformer utilization factor. (43% chose this)
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When viewing NMEA 2000 data you must use the following.
  • Voltmeter (4% chose this)
  • Converter (7% chose this)
  • HyperTerminal (52% chose this)
  • Gateway (37% chose this)
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How many sidebands does a VHF FM transmitter have?
  • One (8% chose this)
  • Two (44% chose this)
  • One to four (6% chose this)
  • Many (42% chose this)
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If the vessel is experiencing atmospheric interference with NAVTEX broadcasts, especially in the tropics, the GMDSS operator should:
  • Select one of the 6 HF MSI frequencies and set-up the transceiver in ARQ TELEX mode. (16% chose this)
  • Select one of the 8 HF MSI frequencies and set-up the transceiver in FEC TELEX mode. (40% chose this)
  • Select one of the 6 MF MSI frequencies and set-up the transceiver in FEC TELEX mode. (26% chose this)
  • Select the MF MSI frequency dedicated to tropical MSI and set-up the transceiver in FEC TELEX mode. (18% chose this)
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What action should be taken if an Inmarsat Fleet Broadband antenna continuously changes azimuth after initialization?
  • Replace the gyro repeater motor in the Antenna Tracking Unit. (25% chose this)
  • Use the Web interface to check the event log. (38% chose this)
  • Check the EL step motor with power off. (17% chose this)
  • Check the integrity of the antenna interface cable. (19% chose this)
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What are the different modes of charging for a GMDSS compliant battery charger/supply?
  • Charging, Change-over, Parallel (36% chose this)
  • Charging, float, trickle (41% chose this)
  • Charging, Full, Trickle (18% chose this)
  • Boots, Full, Float (5% chose this)
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In an Ethernet network, the available bandwidth is shared between all nodes within the same:
  • Vessel Compartment (4% chose this)
  • Address Range (43% chose this)
  • Star Topology (11% chose this)
  • Collision Domain (43% chose this)
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Which of the following statements about a switching mode power supply input current is correct?
  • It has high harmonic content and a low power factor. (40% chose this)
  • It has low harmonic content and a low power factor. (8% chose this)
  • It has high harmonic content and a high power factor. (29% chose this)
  • It has low harmonic content and a high power factor. (23% chose this)
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Which of the following are assigned frequencies for Digital Selective Calling?
  • 2182 kHz, 4177.5 kHz, 6312 kHz, 8376.5 kHz, 12577 kHz, 16420 kHz. (27% chose this)
  • 2187.5 kHz, 4207.5 kHz, 6312 kHz, 8414.5 kHz, 12577 kHz, 16804.5 kHz. (40% chose this)
  • 2187.5 kHz, 4207.5 kHz, 6268 kHz, 8414.5 kHz, 12520 kHz, 16420. kHz. (13% chose this)
  • 2174.5 kHz, 4125 kHz, 6312 kHz, 8291 kHz, 12577 kHz, 16804.5 kHz (19% chose this)
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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?
  • A fault in the transmitter's Push-To-Talk circuit is causing the loss of audio. (46% chose this)
  • There is an open connection in the microphone cable or connector. (44% chose this)
  • The microphone's Automatic Gain Control (AGC) has malfunctioned. (6% chose this)
  • Degenerative feedback applied to the AF amplifier exceeds specifications. (4% chose this)
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Which of the following best describes Inmarsat BGAN Streaming Data service?
  • A service ideal for TCP/IP traffic such as e-mail, file transfers and Internet access. (28% chose this)
  • Exclusive, high-priority connection ideal for time critical applications. (42% chose this)
  • A service used by the Inmarsat terminal's web interface for operation and configuration. (19% chose this)
  • A high speed data service used for high speed connections via ISDN. (11% chose this)
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Which of the following conditions could cause zero RF output in a MF/HF transmitter operating in the F1B FEC mode?
  • The connection of a transceiver is connected to a "Dummy Load" antenna. (38% chose this)
  • The failure of the voice bandpass filter in the stage preceding the RF amplifier. (13% chose this)
  • The activation of a "crowbar" circuit in the power supply to prevent an unregulated voltage increase. (39% chose this)
  • The generation of a positive VCO feedback signal to a Phase Locked Loop circuit in the transmitter. (11% chose this)
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How often should high charging be use with a standard lead acid battery and a fully automatic GMDSS compliant Battery charger?
  • Once every 24 hours for 1 hour. (11% chose this)
  • Once every month till the battery reaches 2.5V/cell. (7% chose this)
  • Never use High charging rate on a fully charged battery. (42% chose this)
  • Once a week till the battery reaches the gassing range. (40% chose this)
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The Voltage of the NMEA 2000 backbone power supply pair must be maintained to within the following range.
  • 0 to 5 volts (9% chose this)
  • 9 to 16 volts (49% chose this)
  • 10.5 to 13.6 volts (24% chose this)
  • 12 to 24 volts (18% chose this)
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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?
  • Insert a directional wattmeter between the VHF transmitter and the coaxial transmission line connected to the antenna, activate the Push-To-Talk (PTT) circuit, observe the measured values of forward and reflected power. (43% chose this)
  • Insert a SWR meter between the VHF transmitter and the coaxial transmission line disconnected from the antenna, set the radio to an unused channel, activate the Push-To-Talk circuit, and read the measured value. (30% chose this)
  • Insert a directional wattmeter between the VHF radio and an artificial antenna, set the radio to any channel, key the microphone, and read the values of forward and reflected power. (11% chose this)
  • Insert an in-line RF Power meter between the VHF transmitter and the coaxial transmission line connected to a 50 ohm load, activate the Push-To-Talk (PTT) circuit, observe the measured value of reflected power. (17% chose this)
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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?
  • The AF Power Amplifier (PA) may be malfunctioning when the transmitter operates in the high power mode. (35% chose this)
  • Negative feedback in the PA stage may be preventing high amplitude oscillations in the high power mode. (8% chose this)
  • The transmitter output is low in the high power mode but it is still functioning within FCC specifications. (48% chose this)
  • The transmitter output will increase in the high power mode with modulation between 75 and 100 percent. (8% chose this)
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How does a noise blanker circuit work in a HF receiver?
  • A limiter circuit clips the peaks of the noise pulses. (12% chose this)
  • The noise pulses are used to develop a blanking pulse for the I.F. amplifier. (45% chose this)
  • The noise pulses operate on the ratio detector to blank the audio output. (8% chose this)
  • A Noise blanker briefly reduces the gain of the RF amplifier when the noise pulses occur. (35% chose this)
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Which of the following is not an accurate list of functions/data recorded by the Vessel Data Recorder?
  • Position, Date, Time and Speed. (17% chose this)
  • Heading, VHF radio communications, Position and Depth of water. (15% chose this)
  • Heading, Depth of water, EGC data and Radar. (44% chose this)
  • Depth of water, Audio from the bridge, Speed and Position. (23% chose this)
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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?
  • The 3 - 30 MHz amplifier stage has failed. (13% chose this)
  • The speaker is shorted out. (38% chose this)
  • Excess negative feedback is reducing AF gain. (7% chose this)
  • The audio amplifier stage has failed. (42% chose this)
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How often must the automatic release mechanism be replaced.
  • Every 2 years (39% chose this)
  • Every 3 years (17% chose this)
  • Every 5 years (37% chose this)
  • Every 8 years (7% chose this)
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What is the correct frequency shift and sub-carrier for VHF-DSC?
  • 1300-2100 Hz, sub-carrier 1700 Hz. (50% chose this)
  • 1500-2300 Hz, sub-carrier 1900 Hz. (17% chose this)
  • 1200-2600 Hz, sub-carrier 1900 Hz. (10% chose this)
  • 1500-2300 Hz, sub-carrier 1700 Hz. (23% chose this)
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How is pre-emphasis used in an FM transceiver?
  • The lower modulation frequencies are boosted before transmitting by 3 db per octave and reduced by the same amount at the receiver. (24% chose this)
  • The higher modulation frequencies are boosted before transmitting by 6 db per octave and reduced by the same amount at the receiver. (44% chose this)
  • The lower modulation frequencies are boosted before transmitting by 6 db per octave and reduced by the same amount at the receiver. (22% chose this)
  • The higher modulation frequencies are boosted before transmitting by 3 db per octave and reduced by the same amount at the receiver. (11% chose this)
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Which of the following is the correct Fax/Data configuration of a Fleet Broadband terminal?
  • RJ11 Port 1 and 2 set to standard voice. (27% chose this)
  • ISDN Port set to standard voice. (12% chose this)
  • RJ11 Port 1 and 2 set to 3.1 kHz audio. (49% chose this)
  • LAN Ports set to 3.1 kHz audio. (12% chose this)
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The antenna creeps up and down after initialization. What action would you take?
  • Check AZ step motor with power off. If it is stiff replace the motor. (12% chose this)
  • Check EL step motor with power off. If it is stiff replace the motor. (47% chose this)
  • Replace the platform sensor. (29% chose this)
  • Replace the gyro repeater motor. (12% chose this)
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Which of the following best describes the GPS satellite signals transmitted?
  • The L2 carrier at 1650.5 MHz carries the navigation message and the L1 carrier at 1575.42 MHz is used to measure the ionospheric delay. (18% chose this)
  • The two carriers are combined in a mixer circuit to develop an intermediate signal which is transmitted. (18% chose this)
  • The main carrier of 1650.5 MHz and a sub-carrier of 1575.24 MHz containing the SPS code signals. (18% chose this)
  • The L1 carrier of 1575.42 MHz carries the navigation message and the SPS code signals and the L2 carrier 1227.60 MHz which is used to measure the ionospheric delay. (47% chose this)
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The current and most recent version of NMEA 0183 uses what standard for data communications?
  • RS422 (44% chose this)
  • RS485 (5% chose this)
  • RS232 (38% chose this)
  • ISO 11783 (13% chose this)
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If the vessel is beyond range of NAVTEX broadcasts and the Sat-C system fails, the GMDSS operator must:
  • Select an HF MSI frequency and FEC TELEX mode to receive MSI. (49% chose this)
  • Select 518 kHz ARQ TELEX on the MF/HF console to receive MSI. (16% chose this)
  • Request repairs of the Sat-C system and wait until within range of NAVTEX. (2% chose this)
  • Select 518 kHz FEC TELEX on the MF/HF console to receive MSI. (33% chose this)
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What statement is false concerning DSC calls addressed to MMSI 003669999?
  • MMSI 003669999 is an established group call that includes all U.S. Coast Guard Stations. (13% chose this)
  • DSC calls to MMSI 003669999 will be received by all DSC-equipped USCG coast stations within radio range. (19% chose this)
  • DSC calls to MMSI 003669999 may not be used to test MF/HF DSC equipment aboard ships. (50% chose this)
  • DSC calls to MMSI 003669999 may result in an automated acknowledgement from USCG coast stations. (19% chose this)
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LRIT Long Range Information Tracking: 
  • Can serve as duplicate back up information for AIS (Automatic Information System.) (30% chose this)
  • Works on the same frequencies as AIS, but on different channels. (12% chose this)
  • is detected on the Inmarsat-C satellite network. (48% chose this)
  • Puts out a polling signal on the Inmarsat B system. (10% chose this)
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How many NCS's operate in each Inmarsat ocean region per Inmarsat system?
  • Three (19% chose this)
  • Four (27% chose this)
  • Two (8% chose this)
  • One (46% chose this)
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With a fully automatic GMDSS compliant battery charger / power supply, when must the high charging process be interrupted?
  • To keep the battery from overheating. (43% chose this)
  • To keep the battery electrolyte from reaching 212 degrees F. (9% chose this)
  • To inhibit the generation of electrolytic gas. (44% chose this)
  • To keep the battery as cool as possible. (4% chose this)
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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?
  • The antenna system is presenting a Standing Wave Ratio (SWR) of 1.5 to 1.0 on the desired frequency. (5% chose this)
  • The SWR protection circuit in the transmitter has engaged to prevent damage to the Power Amplifier. (43% chose this)
  • A "crowbar" circuit in the power supply has prevented an over current condition that might damage the radio. (48% chose this)
  • A 50-ohm impedance in the antenna system is preventing the transmitter from achieving full power output. (4% chose this)
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If a vessel is within range of NAVTEX broadcasts and both the Inmarsat-C and the NAVTEX receiver are inoperative the GMDSS operator should:
  • Select 518 kHz FEC TELEX on the MF/HF console to receive MSI. (46% chose this)
  • Select 518 kHz ARQ TELEX on the MF/HF console to receive MSI. (17% chose this)
  • Request repairs of the Sat-C system and wait until within range of NAVTEX. (2% chose this)
  • Select an HF MSI frequency and ARQ TELEX mode to receive MSI. (35% chose this)
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When installing an Inmarsat-C antenna what should be the minimum distance to other Inmarsat antennas?
  • 4 meters (23% chose this)
  • 8 meters (48% chose this)
  • 10 meters (17% chose this)
  • 12 meters (12% chose this)
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What precedes the phasing signal in a DSC distress alert call?
  • An alternating dot pattern of 20 bits (23% chose this)
  • An alternating dot pattern of 100 bits (15% chose this)
  • An alternating dot pattern of 200 bits (47% chose this)
  • An alternating dot pattern of 400 bits (15% chose this)
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AIS units use the following:
  • VHF channels 65B ( 160.875 MHz) and 66B ( 160.925 MHz) and 9.6 kbs GMSK modulation. (14% chose this)
  • VHF channels 87B (161.975 MHz) and 88B (162.025 MHz) and 9.6 kbs GMSK modulation. (43% chose this)
  • VHF channels 16 ( 158.800 MHz) and 70 ( 156.525 MHz) and 4.8 kbs GMSK modulation. (29% chose this)
  • VHF channels 18B ( 161.500 MHz) and 19B ( 161.550 MHz) and 4.8 kbs GMSK modulation. (14% chose this)
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How is accuracy insured in NAVTEX broadcasts?
  • A parity check character is sent at the end of each line. (30% chose this)
  • Each message is retransmitted. (4% chose this)
  • Selective FEC is used to prevent errors. (19% chose this)
  • Each character is sent twice with a time interval. (47% chose this)
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What error message may be displayed if a connection to the Inmarsat Mobile Packet Data Service (MPDS) network fails?
  • "ECM 0071" is displayed indicating the called station ID was not properly decoded. (6% chose this)
  • "ECM 00F0" is displayed indicating the terminal's failure to transmit over the Inmarsat network. (14% chose this)
  • "77F0h" or "77F1h" is displayed indicating the terminal is not registered to the MPDS network. (29% chose this)
  • "00F0h" or "00F1h" is displayed indicating the terminal is not registered to the MPDS network. (51% chose this)
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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?
  • Replace the AZ or EL motor in the above deck equipment. (4% chose this)
  • Try logging into a different satellite with the original ADE. (19% chose this)
  • Use a DVM to check the feedline between the terminal and ADE. (23% chose this)
  • Install a replacement ADE. (53% chose this)
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A good lab type signal generator for VHF measurements should be able to reduce its output to:
  • 5.0 microvolt (7% chose this)
  • 1.0 microvolt (29% chose this)
  • 0.5 microvolt (18% chose this)
  • 0.1 microvolt (45% chose this)
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What is the configuration for a mains operated switching power supply with output regulation?
  • Input rectifier and filter, Inverter (chopper), output transformer, feedback loop to a chopper controller and inverter and output rectifier and filter to DC output. (20% chose this)
  • Line, Inverter (chopper), input rectifier and filter, output transformer, output rectifier and filter to DC output. (20% chose this)
  • Input rectifier and filter, output transformer, output rectifier and filter to DC output with feedback loop to the input followed by the chopper controller. (13% chose this)
  • Input rectifier and filter, Inverter (chopper), output transformer, output rectifier and filter to DC output with feedback loop to a chopper controller and the inverter. (46% chose this)
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What are the frequencies for Inmarsat-C shipboard satellite operation?
  • Reception: 1526.5 - 1560.5 MHz and Transmission: 1625.0 - 1659.0 MHz (17% chose this)
  • Reception: 1625.0 - 1659.0 MHz and Transmission: 1526.5 - 1560.5 MHz (13% chose this)
  • Reception: 1530.0 - 1545.0 MHZ and Transmission: 1626.5 - 1645.5 MHz (48% chose this)
  • Reception: 1625.0 - 1659.0 MHz and Transmission: 1526.5 - 1560.5 MHz (21% chose this)
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The MF/HF transceiver produces strong AF output but no signals are heard on any frequency. What is the most likely cause?
  • The transceiver is connected to a "Dummy Load." (47% chose this)
  • A high Standing Wave Ratio (SWR) in the antenna system. (11% chose this)
  • A "crowbar" circuit in the power supply is activated. (23% chose this)
  • The squelch circuit has failed. (19% chose this)
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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?
  • Intermittent gain in the AF amplifier circuit. (10% chose this)
  • The squelch sensitivity control is set too high. (27% chose this)
  • An intermittent connection between the antenna and coupler. (51% chose this)
  • The AGC circuit has malfunctioned. (12% chose this)
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You are able to hear signals in the SITOR (NBDP) mode but not in the voice/SSB mode. What is the most likely cause?
  • The B.F.O. circuit has failed. (28% chose this)
  • The audio amplifier is defective. (17% chose this)
  • The 2.8 kHz filter has become defective. (45% chose this)
  • The R.F. amplifier has failed. (10% chose this)
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What is a disadvantage when using high gain VHF antennas?
  • Poor horizontal radiation pattern. (14% chose this)
  • Very high radiation pattern. (22% chose this)
  • Very low radiation pattern. (20% chose this)
  • Signal dropout in severe weather on small craft. (44% chose this)
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What condition may cause distortion in the modulator stage of a marine VHF transmitter?
  • The reactance modulator may be out of alignment. (15% chose this)
  • The excessive use of pre-emphasis on audio signals above 25 kHz. (23% chose this)
  • A defective varactor diode in the transmitter's voltage controlled oscillator. (20% chose this)
  • Transmitter modulation in excess of 150%. (43% chose this)
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The antenna tries to initialize then points straight up and stops. What is the most likely problem?
  • A defective EL motor. (21% chose this)
  • A defective AZ motor. (17% chose this)
  • A defective level platform sensor. (49% chose this)
  • A defective I.F. amplifier. (13% chose this)
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If the BFO is turned off what kind of emissions can still be received?
  • J3E and J2B (21% chose this)
  • A3E and H3E (46% chose this)
  • H3E and F1B (21% chose this)
  • A1A and J3E (11% chose this)
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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?
  • The audio amplifier is defective. (7% chose this)
  • The wrong frequency has been selected. (48% chose this)
  • The RF amplifier at the antenna base is defective. (43% chose this)
  • The DC supply voltage is too low. (2% chose this)
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What is the function of a properly adjusted limiter circuit?
  • Maintains a constant output amplitude with a varying input amplitude. (45% chose this)
  • Limits the level of RF output power in the final amplifier stage. (36% chose this)
  • Limits the modulation input amplitude while amplifying the modulation output. (16% chose this)
  • Controls the DC input voltage excursions of the final amplifier stage. (3% chose this)
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Which would indicate proper operation of a SSB transmitter rated at 60 Watt PEP output in J3E mode?
  • In SITOR communications, the power meter can be seen fluctuating regularly from zero to the 60 watt relative output reading. (47% chose this)
  • In SSB (J3E) voice mode, with the transmitter keyed but without speaking into the microphone, no power output is indicated. (46% chose this)
  • In SSB (J3E) mode, speaking into the microphone causes the power meter to fluctuate well above the 60 watt reading. (4% chose this)
  • A steady indication of transmitted energy on an RF power meter with no fluctuations when speaking into the microphone. (4% chose this)
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The voice is garbled and unreadable on MF/HF SSB channels. What is the most likely cause?
  • The R.I.T circuit has failed. (22% chose this)
  • The first RF stage has failed. (13% chose this)
  • The frequency synthesizer has failed. (18% chose this)
  • The beat frequency oscillator circuit has failed. (47% chose this)
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The AGC function of an MF/HF receiver is inoperative. What is the most likely cause?
  • The B.F.O. circuit has failed. (17% chose this)
  • The Voltage controlled Oscillator is inoperative. (31% chose this)
  • The audio amplifier is defective. (7% chose this)
  • Failure of a variable gain amplifier in the RF stage. (45% chose this)
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What is the modulation index?
  • The maximum carrier deviation divided by the maximum modulation frequency. (47% chose this)
  • The maximum modulation frequency divided by the maximum carrier frequency. (29% chose this)
  • The maximum carrier deviation multiplied by the maximum carrier frequency. (12% chose this)
  • The maximum carrier deviation divided by the amount of pre-emphasis. (12% chose this)
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How does the Ship Security Alert System operate?
  • It sends an alert to specific addresses via the Inmarsat-C terminal. (55% chose this)
  • It sends an all ships alert via the VHF-DSC unit. (14% chose this)
  • It sends an alert to the RCC via the Inmarsat-C terminal. (22% chose this)
  • It sends an all ships alert via MF-HF. (8% chose this)
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What is the frequency separation between Transmit and Receive frequencies on a duplex channel?
  • 2.8 MHz (27% chose this)
  • 4.6 MHz (37% chose this)
  • 6.4 MHz (19% chose this)
  • 10.7 MHz (16% chose this)
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A fully automatic GMDSS compliant Battery charger/ Power supply's high (Full) charging mode must be disabled during setup for what type batteries?
  • When the batteries are Ni Cadmium type. (7% chose this)
  • When the Batteries are standard lead acid type. (15% chose this)
  • When the batteries are lithium ion type. (28% chose this)
  • When the batteries are Maintenance free lead acid gel type. (50% chose this)
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When is a PIN Unlock Key (PUK) used with an Inmarsat terminal?
  • To place a credit card telephone call via the Inmarsat terminal. (6% chose this)
  • To input the Personal Identification Number (PIN) applied to a telephone extension. (27% chose this)
  • To override a long distance block on an Inmarsat terminal. (12% chose this)
  • To unlock the SIM card in a Fleet broadband terminal. (55% chose this)
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What is the purpose of the Dual Watch function?
  • Allows simultaneous reception on two different channels. (40% chose this)
  • To rapidly switch the radio's receiver between two channels. (47% chose this)
  • Allows reception and transmission at the same time. (3% chose this)
  • It allows you to monitor both sides of a public correspondence station's communication. (10% chose this)
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What is the electrical effect of a capacitance in series with the antenna?
  • It electrically lengthens a physically fixed length antenna. (29% chose this)
  • It electrically shortens a physically fixed length antenna. (56% chose this)
  • It lowers the resonant frequency of a physically fixed length antenna. (6% chose this)
  • It increases the bandwidth of a physically fixed length antenna. (8% chose this)
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Which of the following conditions indicate the proper operation of a 150 Watt MF/HF transmitter in the F1B ARQ mode?
  • The RF power meter indicates constant output at a level between 125 watts and 150 watts during transmission. (35% chose this)
  • The RF power meter indicates power output only when characters are typed on the NBDP keyboard. (9% chose this)
  • The RF "S" meter indicates a signal level between 125 watts and 150 watts during NBDP reception. (7% chose this)
  • The RF power meter indicates an output that fluctuates between 0 and 150 watts during transmission. (49% chose this)
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What inputs are normally required for an Auto Pilot?
  • Course information and GPS. (22% chose this)
  • Rudder feedback and Radar data. (20% chose this)
  • Course information and rudder feedback. (49% chose this)
  • Rudder feedback and yaw sensors. (9% chose this)
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What are the four main functions of the "BIOS" in most computers?
  • BIOS Drivers, Bootstrap Loader, Printer Driver and BIOS Setup. (12% chose this)
  • CPU Setup, Disc Partition, USB driver and BIOS Setup. (12% chose this)
  • P.O.S.T., Bootstrap Loader, BIOS Drivers and BIOS Setup. (54% chose this)
  • BIOS Setup, P.O.S.T., CPU Setup and RAM Setup. (22% chose this)
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A MF/HF Distress priority DSC call may be formatted to include the following:
  • MMSI, vessel position, nature of distress, follow-on communications by J3E only. (13% chose this)
  • MMSI, vessel position, nature of distress, follow-on communications by J3E or F1B. (53% chose this)
  • Call sign, vessel position, nature of distress, follow-on communications by J3E or F1B. (13% chose this)
  • Name of vessel, vessel position, nature of distress, follow-on communications by J3E or F1B. (21% chose this)
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What are the main advantages of using switcher type power supply?
  • Line voltage is directly rectified and filtered to produce a high dc voltage, components are much smaller and lighter weight, can provide much better efficiency. (55% chose this)
  • The transformed voltage is directly rectified and filtered to produce a high dc voltage, components are much smaller and lighter weight and can provide much better efficiency. (35% chose this)
  • They use laminated steel transformers which are more efficient. (2% chose this)
  • Using a center tapped transformer secondary allows fewer rectifiers to be used. (8% chose this)
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What is the primary purpose of both a high and a low I.F. system in a HF receiver?
  • Using a high first I.F. amplifier results in eliminating image signals. (52% chose this)
  • Using a high first I.F. amplifier results in less intermodulation products. (13% chose this)
  • Using a low first I.F. amplifier results in fewer third harmonic signals. (19% chose this)
  • Using a low first I.F. amplifier results in greater signal amplification. (17% chose this)
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How do you determine the type of disc drives in an XP system?
  • Click on Start programs, accessories and system information. (52% chose this)
  • Click on System information then Disc Drives. (39% chose this)
  • Click on Control panel then Sounds and Audio Devices. (7% chose this)
  • Click on Control panel followed by Taskbar and Start Menu. (2% chose this)
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NMEA 2000 Certified Device identify their current requirements in terms of LENs (load Equivalent Number). 1 LEN is equal to:
  • 1 Amp (15% chose this)
  • 500 mA (17% chose this)
  • 50 mA (47% chose this)
  • 25 mA (22% chose this)
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Which of the following conditions would indicate the malfunction of a 2182 kHz radiotelephone system?
  • No discernable traffic has been heard on the 2182 kHz during the radiotelephone silent periods. (7% chose this)
  • Failure to contact another station 60 miles distant during daytime operation. (52% chose this)
  • Dramatic decrease in noise level observed during night and early morning hours. (2% chose this)
  • The visual indication of power to the antenna fluctuates while testing the radiotelephone alarm signal generator into an artificial antenna. (39% chose this)
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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.
  • 2181.991 kHz and 4125.004 kHz (29% chose this)
  • 2182.006 kHz and 4124.995 kHz (48% chose this)
  • 2182.010 kHz and 4124.992 kHz (14% chose this)
  • 2181.990 kHz and 4125.009 kHz (9% chose this)
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What are the characters that are transmitted to terminate a direct TELEX connection in SITOR (NBDP) operations?
  • KKKK (62% chose this)
  • . . . . . (7% chose this)
  • END+ (20% chose this)
  • EOM (11% chose this)
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What is the fade margin factor?
  • A design allowance that provides for the sun to accommodate expected fading for the purpose of ensuring that the required quality of service is maintained. (27% chose this)
  • A design allowance to accommodate expected fading. (44% chose this)
  • The increase in fade over a receiver's noise floor. (16% chose this)
  • The ratio between the largest and smallest values of a received signal. (14% chose this)
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What is the most common method of generating a SITOR (NBDP) signal on shipboard GMDSS equipment?
  • Two alternating sidebands of 1615 Hz and 1785 Hz are offset from the carrier frequency by 1700 Hz. (51% chose this)
  • The carrier frequency is alternately shifted from + 85 Hz to - 85 Hz while suppressing the sidebands. (15% chose this)
  • There is one 1500 Hz sideband which is shifted from +170 Hz to - 170 Hz with a suppressed carrier. (20% chose this)
  • Two alternating sidebands of 1500 Hz and 2300 Hz are offset from the carrier frequency by 1900 Hz. (15% chose this)
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Which of the following is not recommended for Inmarsat-C antenna installations?
  • Ensure the antenna is electrically insulated from the mounting mast. Check resistance with ohmmeter. (56% chose this)
  • Ground the antenna chassis to the mounting mast. Apply silicone to weatherproof the connection. (22% chose this)
  • Fashion a drip loop in the transmission line near the antenna. Secure to the mounting mast with cable tie. (14% chose this)
  • Apply waterproof sealant or putty around transmission line connectors. Wrap with self-bonding/vinyl tape. (8% chose this)
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Which of the following statements concerning power supply filters is true?
  • A capacitor input has high output voltage, good voltage regulation, low rectifier peak currents and low transformer utilization factor. (19% chose this)
  • A capacitor input has low output voltage, poor voltage regulation, high rectifier peak currents and low transformer utilization factor. (13% chose this)
  • An Inductive input has poor voltage regulation, low transformer utilization factor, high rectifier peak currents and relative low output voltage. (15% chose this)
  • An Inductive input has good voltage regulation, high transformer utilization factor, low rectifier peak currents and relatively low output voltage. (53% chose this)
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What is the correct frequency shift and sub-carrier for MF-HF-DSC?
  • +/- 85 Hz and 1700 Hz (55% chose this)
  • +/- 170 Hz and 1700 Hz (11% chose this)
  • +/- 250 Hz and 1500 Hz (17% chose this)
  • +/- 400 Hz and 1900 Hz (17% chose this)
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Which of the following statements about switching power supplies is the most accurate?
  • Transformers use a ferrite core to reduce losses at high frequencies. (56% chose this)
  • Transformers use a laminated steel core to reduce losses at high frequencies. (12% chose this)
  • Lower switching frequencies provide better voltage regulation. (12% chose this)
  • Higher switching frequencies are more difficult to filter. (21% chose this)
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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?
  • Defective AZ or EL motor in the above deck equipment. (7% chose this)
  • Blown line fuse in the terminal's DC power supply. (23% chose this)
  • Blown antenna power fuse in the above deck equipment. (51% chose this)
  • Defective Low Noise Amplifier in the above deck equipment. (19% chose this)
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Which of the following conditions indicate the proper operation of a 250 Watt MF/HF transmitter in the F1B FEC mode?
  • The RF power meter indicates constant output at a level between 225 watts and 250 watts during transmission. (53% chose this)
  • The RF power meter indicates power output only when characters are typed on the NBDP keyboard. (9% chose this)
  • The RF "S" meter indicates a signal level between 225 watts and 250 watts during NBDP reception. (4% chose this)
  • The RF power meter indicates an output that fluctuates between 0 and 250 watts during transmission. (35% chose this)
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What is the maximum length of a USB 2.0 cable between two hubs or between a hub and peripheral?
  • 5 meters (56% chose this)
  • 10 meters (19% chose this)
  • 15 meters (12% chose this)
  • 20 meters (13% chose this)
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Which of the following Inmarsat units stores configuration data and contains all user interfaces and LED indicators?
  • Main Control Unit - an element of the Pedestal Control Assembly. (26% chose this)
  • Master Communications Unit - an element of the antenna control unit. (6% chose this)
  • Master Communications Unit - an element of the RF transceiver. (15% chose this)
  • Fleet Broadband terminal - a component of below deck equipment. (54% chose this)
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What would be the most likely power level to use for initial MF-HF communications?
  • 25 watts PEP (30% chose this)
  • 50 watts PEP (13% chose this)
  • 150 watts PEP (55% chose this)
  • 600 watts PEP (2% chose this)
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Which of the following conditions could cause very low RF output in a MF/HF transmitter operating in the F1B FEC mode?
  • Failure of a voltage controlled oscillator in the IF amplifier stage. (15% chose this)
  • A high Standing Wave Ratio (SWR) in the antenna system. (53% chose this)
  • The connection of a transceiver is connected to a "Dummy Load" antenna. (16% chose this)
  • Failure of a SSB bandpass filter in the stage preceding the RF amplifier. (16% chose this)
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What condition may cause a significant loss in VHF receiver sensitivity?
  • A reading of 9.6 when a voltmeter is connected between the positive side of the radio's DC line and ground. (52% chose this)
  • The presence of a -90dbm signal measured at the 2nd IF output with the receiver tuned to the desired input frequency. (18% chose this)
  • An internal signal that is very weak in comparison to the desired signal at the output of the second IF stage. (21% chose this)
  • Replacing (75 ohm) RG-59/U coaxial transmission line with a (50 ohm) RG-8/U or LMR-400 Ultraflex cable. (9% chose this)
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What is a common range of frequencies used for depth finding equipment?
  • 200-400 kHz (57% chose this)
  • 1000-2600 kHz (12% chose this)
  • 200-800 Hz (16% chose this)
  • 4,000-6,000 kHz (16% chose this)
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Which of the following statements is true?
  • The L2 carrier of 1227.60 MHz is used to measure the ionospheric delay. (58% chose this)
  • The L1 carrier of 1650.5 MHz is used to measure the ionospheric delay. (15% chose this)
  • The L1 carrier of 1545.22 MHz is used to provide the navigation message. (15% chose this)
  • The L2 carrier of 1575.42 MHz is used to provide the navigation message. (12% chose this)
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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?
  • The speaker is shorted out. (6% chose this)
  • A shorted Push-To-Talk circuit in the microphone. (57% chose this)
  • A "crowbar" circuit in the power supply has engaged. (19% chose this)
  • The final stage of the AF amplifier circuit has failed. (19% chose this)
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What log entries are required after passing the annual inspection?
  • One of the ship's GMDSS Radio Operators must certify that inspecting technician as properly conducted all the required equipment tests. (13% chose this)
  • The inspecting technician must enter the results of all the equipment tests and specifically note which tests passed and which tests failed. (17% chose this)
  • Certification by both the inspecting technician and the vessel's Master/owner that the inspection was successful. (65% chose this)
  • The vessel's Master/Owner must certify that the inspection was successful. (4% chose this)
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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?
  • 23.74 to 24.52 volts DC (26% chose this)
  • 23.62 to 24.38 volts DC (53% chose this)
  • 23.56 to 24.28 volts DC (12% chose this)
  • 23.42 to 24.52 volts DC (9% chose this)
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What action must be taken after an Inmarsat-C system is fully installed?
  • Advise the nearest RCC that your terminal is active. (12% chose this)
  • Send a distress alert and then cancel it. (2% chose this)
  • Your Inmarsat Mobile Number must be entered in the terminal. (60% chose this)
  • Send a brief test message to your own terminal. (26% chose this)
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What is the purpose of the "carbon pile" on an older gyro compass?
  • Ballast regulation (11% chose this)
  • Precession control (13% chose this)
  • Voltage regulation (48% chose this)
  • Prevent pendulum effect errors (29% chose this)
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How often must the EPIRB battery be replaced?
  • Every 2 years. (20% chose this)
  • Every 3 years or after use. (24% chose this)
  • Every 5 years or after use. (56% chose this)
  • Every 8 years. (0% chose this)
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What condition may cause noisy operation of a VHF receiver?
  • An output signal that is larger than the input signal in an audio frequency amplifier stage. (19% chose this)
  • A defective potentiometer in the audio frequency amplifier stage. (58% chose this)
  • Low bias voltage to an intermediate frequency amplifier stage. (15% chose this)
  • An open winding in a secondary of a coupling transformer in the audio frequency amplifier stage. (8% chose this)
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What is the allowed frequency tolerance for the DSC carrier frequencies?
  • 10 Hz (24% chose this)
  • 20 Hz (10% chose this)
  • 5 ppm (15% chose this)
  • 10 ppm (51% chose this)
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What is the purpose of the Differential GPS system and how does it work?
  • To measure the difference between L-1 and L-2 signals and transmit the information via the GPS signal. (21% chose this)
  • To correct for time errors in the satellites and transmit this information via the GPS signal. (17% chose this)
  • To correct for various errors using a fixed receiving station which transmits corrections via radio signals. (52% chose this)
  • To correct for phase errors between L-1 and L-2 signals and transmit the information via radio beacons. (10% chose this)
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How is a J3E signal generated?
  • By using high-level modulation to produce a single sideband. (15% chose this)
  • By using a double balanced mixer and a sideband filter. (57% chose this)
  • By using the audio signal to phase modulate the carrier. (13% chose this)
  • By using low level modulation and a sideband filter. (15% chose this)
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Which of the following keystrokes or characters follows most commands in ARQ communications when working an automated Coast Station?
  • + (53% chose this)
  • GA+? (11% chose this)
  • ENTER (21% chose this)
  • END (16% chose this)
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An Inmarsat-C terminal will not "LOG IN" and shows an "Antenna not connected" alarm. What action would you take?
  • Short one end of coax cable. If the resistance is above one ohm replace the cable. (59% chose this)
  • Change to a different satellite and try a new "LOG IN". (22% chose this)
  • Replace the antenna unit. (18% chose this)
  • Replace the AZ-EL board. (2% chose this)
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The MF/HF transceiver produces strong AF output but no signals are heard on any frequency. What is the most likely cause?
  • The squelch sensitivity control is set too high. (27% chose this)
  • There is an open circuit in the transmission line to the antenna. (48% chose this)
  • The final stage of the AF amplifier circuit has failed. (13% chose this)
  • The power amplifier stage in the receiver has failed. (13% chose this)
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The phase locked loop circuit in an MF/HF receiver appears to be faulty. What is the most likely cause?
  • The AGC circuit has become defective. (6% chose this)
  • The Beat Frequency Oscillator is inoperative. (24% chose this)
  • The Voltage Controlled Oscillator is inoperative. (56% chose this)
  • The 500 Hz I.F. filter has become defective. (15% chose this)
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What are the principles of operation of a fiber-optic gyro compass?
  • A fiber-optic coil and three accelerometers determine the speed of rotation of the earth. (17% chose this)
  • Two fiber-optic coils with one accelerometer and a level sensor determine the direction of true north. (6% chose this)
  • Three fiber-optic coils with a dual accelerometer and a yaw detector determines the direction of true north. (21% chose this)
  • Three fiber-optic coils and a dual-axis electronic level sensor determine the direction of true north. (57% chose this)
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Which would be an indication of proper operation of a SSB transmitter rated at 60 watt PEP output?
  • In SSB (J3E) voice mode, with the transmitter keyed but without speaking into the microphone, power output is indicated. (14% chose this)
  • In SSB (J3E) mode, speaking into the microphone causes power meter to fluctuate slightly around the 60 watt reading. (25% chose this)
  • In SITOR (NBDP) communications, the power meter can be seen fluctuating regularly from zero to the 60 watt relative output reading. (54% chose this)
  • A steady indication of transmitted energy on an RF Power meter with no fluctuations when speaking into the microphone. (7% chose this)
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What components does an Inmarsat Fleet Broadband RADOME typically include?
  • Phased array antenna, gyro-stabilized platform, rotary joint, AC power supply. (16% chose this)
  • Stabilized antenna, RF unit, Antenna Control Unit, GPS antenna. (53% chose this)
  • Parabolic dish antenna, Main Control Unit, rotary joint, HV power supply. (16% chose this)
  • Parabolic dish antenna, rotary joint, AC power supply TDMA Control Unit. (16% chose this)
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which of the following troubleshooting methods is not valid for finding the fault in a MF/HF transmitter operating in the F1B FEC mode?
  • Visual inspection of the transmitter (control settings, signs of physical damage or overheating, etc.) (12% chose this)
  • Power supply testing with a DVM to ensure all prescribed operating voltages are within acceptable limits. (10% chose this)
  • Modulation testing with a RF spectrum analyzer to measure frequency deviation in the transmit mode. (53% chose this)
  • Input/Output checks with a 10:1 oscilloscope probe to identify any points of severe signal degradation. (25% chose this)
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Which of the following best describes the polarization of a satellite signal?
  • The orientation of the RF signal's electric field component. (54% chose this)
  • The orientation of the RF signal relative to a dipole antenna. (12% chose this)
  • The orientation of the RF signal relative to a parabolic antenna. (14% chose this)
  • The orientation of the RF signal's magnetic field component. (19% chose this)
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Which of the following is not a characteristic of an Inmarsat Fleet Broadband IP handset?
  • Ability to transmit telephone calls as circuit-switched calls. (22% chose this)
  • Displays menu options to configure the terminal. (4% chose this)
  • Uses TCP/IP to communicate with the terminal. (18% chose this)
  • Provides the terminal with Power over Ethernet. (56% chose this)
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What do EGC messages contain?
  • Maritime Mobile Service Identity information. (12% chose this)
  • SafeNetTM, FleetwideNetTM and System information. (16% chose this)
  • Electronic Grounding Codes and System information. (12% chose this)
  • SafetyNetTM, FleetNetTM and System information. (61% chose this)
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What would be the most likely reason to observe the transmitter output with a spectrum analyzer?
  • Measure frequency modulation deviation. (22% chose this)
  • Measure percentage of amplitude modulation. (8% chose this)
  • Measure the carrier frequency. (8% chose this)
  • Measure spurious signals. (62% chose this)
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Which of the following is NOT a function of the LAN port on a Fleet Broadband terminal?
  • To provide connectivity to an ISDN telephone handset. (58% chose this)
  • To provide IP connectivity for terminal configuration and troubleshooting. (2% chose this)
  • To provide connectivity for Internet browsing with a computer. (17% chose this)
  • To provide connectivity for a Voice Over IP (VOIP) telephone Handset. (23% chose this)
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Which of the following is a necessary component of an auto pilot?
  • GPS (31% chose this)
  • Rudder feedback unit (53% chose this)
  • Engine RPM data (3% chose this)
  • SSAS (12% chose this)
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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?
  • MSG+ (28% chose this)
  • AMV+ (14% chose this)
  • OPR+ (4% chose this)
  • DIRTLX0xxyyyy+ (54% chose this)
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What is the assigned bandwidth and channel spacing for J2B SITOR (NBDP) transmissions?
  • 3.1 kHz and 4.0 kHz (11% chose this)
  • 2.8 kHz and 3.0 kHz (25% chose this)
  • 170 Hz and 300 Hz (11% chose this)
  • 300 Hz and 500 Hz (54% chose this)
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What is the maximum length for a drop cable to a single NMEA 2000 device?
  • 6 meters (57% chose this)
  • 12 meters (11% chose this)
  • 18 meters (13% chose this)
  • 24 meters (19% chose this)
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What is the configuration for Thrane & Thrane F250 & F500 facsimile operation?
  • Fax - Group 3 fax via standard voice channel for analog fax applications. (17% chose this)
  • Fax - Group 3 fax via 3.1 kHz audio channel for analog fax applications. (57% chose this)
  • Fax - Group 5 fax via 5.1 kHz audio channel for efax applications. (11% chose this)
  • Fax - Group 3 fax via ISDN channel for analog fax applications. (15% chose this)
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What condition will lower the observed bit rate on a Fleet Broadband terminal?
  • A standard IP satellite channel that is "busy" with many active users. (56% chose this)
  • Selection of an upstream IP data service for downstream high-speed data transmission. (9% chose this)
  • Use of the FTP, POP, SMTP or HTTP protocol instead of TCP/IP. (16% chose this)
  • Use of highly contended connections instead of store-and-forward IP circuits. (18% chose this)
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 What condition may prevent a VHF radio receiver from receiving a weak signal?
  • The local oscillator frequency is beating against the incoming signal to produce an Intermediate Frequency (IF). (6% chose this)
  • The output signal of the Phase Locked Loop (PLL) circuit in the frequency synthesizer has become unlocked. (28% chose this)
  • The output signal of an AF amplifier stage is greater than the input signal. (8% chose this)
  • The weak RF signal has been suppressed at the limiter stage of the received by capture effect. (58% chose this)
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The sequence ARQ, FEC, SFEC best corresponds to which of the following sequences?
  • One-way communications to a single station, one-way communications to all stations, two-way communications. (8% chose this)
  • Two way communications, one-way communications to all stations, one-way communications to a single station. (63% chose this)
  • One-way communications to all stations, two-way communications, one-way communications to a single station. (8% chose this)
  • Two way communications, One way communications to a single station, One way communications to all stations. (20% chose this)
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what is the maximum signal voltage range that an NMEA-0183 unit must be capable of handling without damage?
  • +/- 5 volts (19% chose this)
  • +/- 10 volts (14% chose this)
  • +/- 12 volts (12% chose this)
  • +/- 15 volts (54% chose this)
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What is the purpose of the magnet in the EPIRB mounting bracket?
  • To secure the EPIRB in the mounting bracket. (24% chose this)
  • Prevent accidental operation of the EPIRB while secured in the mounting bracket. (54% chose this)
  • To activate the automatic release mechanism. (15% chose this)
  • When the EPIRB is released it causes a signal to be sent to the bridge. (7% chose this)
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What might a voltmeter indicate when testing a DSC circuit for an outgoing message data stream?
  • Steady reading of 12 volts DC. (13% chose this)
  • Fluctuating reading from 0 to 2 volts DC. (57% chose this)
  • There will be an absence of voltage. (9% chose this)
  • Voltage swing from -12 VDC to + 12 VDC. (21% chose this)
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Which of the following is characteristic of the parabolic dish antenna?
  • Feedhorn located behind the parabolic reflector. (10% chose this)
  • Feedhorn adjusted to the focal point of the antenna. (62% chose this)
  • Most often used on high frequencies (3-30 MHz). (17% chose this)
  • Low gain, highly directional radiation pattern. (12% chose this)
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What is the configuration Thrane & Thrane F500 for standard voice telephone operation?
  • RJ11 Port 1 and 2 set to 3.1 kHz. (17% chose this)
  • RJ11 Port 1 and 2 set to standard voice. (59% chose this)
  • ISDN Port set to 3.1 kHz. (11% chose this)
  • ISDN Port 1 and 2 set to standard voice. (13% chose this)
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What is the assigned channel spacing for VHF channels?
  • 10 kHz (24% chose this)
  • 15 kHz (14% chose this)
  • 25 kHz (48% chose this)
  • 50 kHz (14% chose this)
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What procedure must be followed before using C-Map charts for an Electronic Chart System?
  • License information must be entered in the master computer terminal. (7% chose this)
  • The C-Map charts must be downloaded from the internet. (19% chose this)
  • A dongle or password device must be inserted in the master computer terminal. (18% chose this)
  • License information must be entered for each computer being used. (56% chose this)
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Which of the following statements about an NMEA -0183 system is correct?
  • The cable shield must be grounded at both ends including the opto-isolators. (15% chose this)
  • Opto-isolators must be used and the shield should be grounded to the talker chassis only. (60% chose this)
  • Opto-isolators must be used and the shield should be grounded to the listener chassis only. (15% chose this)
  • Version 2 devices use higher voltages than version 1 devices. (9% chose this)
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LRIT Long Range Information Tracking data:
  • Need not be transmitted if AMVER daily messages are sent. (17% chose this)
  • Is a separate tracking system for each flag state's security. (60% chose this)
  • Is shared for the Captain of the Port. (9% chose this)
  • Is broadcast on the Internet for company tracking purposes. (13% chose this)
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An analog RF wattmeter provides the most accurate reading:
  • At the middle one third of the dial. (23% chose this)
  • At the lower one third of the dial. (4% chose this)
  • At the upper one third of the dial. (62% chose this)
  • The accuracy is uniform the whole scale. (12% chose this)
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How do you perform a LOOP BACK test?
  • Initiate a Performance Verification Test through terminal software. (10% chose this)
  • Initiate a test to IP address: 127.0.0.1. (25% chose this)
  • Send yourself a test message. (62% chose this)
  • Request the LES to send you a test message. (4% chose this)
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Which of the following is not a function of an Inmarsat Fleet Broadband IP handset?
  • Polling and Data Reporting. (56% chose this)
  • Voice over IP telephone calls. (19% chose this)
  • Displaying terminal status. (4% chose this)
  • Changing terminal parameters. (21% chose this)
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Which of the following best describes a phased array antenna system?
  • RF from the feedline array is dissipated by a single antenna element. (13% chose this)
  • RF from a multiple feedline array is dissipated by a single antenna element. (9% chose this)
  • RF from multiple antennas is varied to produce a desired radiation pattern. (58% chose this)
  • RF from multiple antennas is combined to produce unity gain. (20% chose this)
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What is the most common type of coax connector used on VHF transceivers?
  • "N" (16% chose this)
  • "BNC" (18% chose this)
  • "UHF" (64% chose this)
  • "TNC" (2% chose this)
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What ohmmeter reading may indicate a faulty component in a VHF receiver?
  • Low resistance across a diode in one direction, high resistance when test leads are reversed. (15% chose this)
  • Zero ohms across an in-line fuse in a DC power circuit. (24% chose this)
  • Infinite ohms across a ceramic bypass capacitor in a transistor amplifier circuit. (4% chose this)
  • A transistor indicates low resistance between emitter and base when test leads are reversed across them. (58% chose this)
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Which of the following may be adjusted in a FM ratio detector for improved signal-to-noise?
  • The diode detector (15% chose this)
  • Input signal to the two diodes (13% chose this)
  • Input voltage to the transistor (8% chose this)
  • Ratio Arm balance control bridge (63% chose this)
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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?
  • Connect the radio to the SPECAN through an in-line attenuator, apply maximum attentuation and set the radio to HIGH power. Use an inductive probe to evaluate signals at the input/output of AF transmitter stages. (9% chose this)
  • Connect the radio to the SPECAN through an in-line attenuator, apply maximum attentuation and switch the radio to HIGH power. Use an inductive probe to evaluate signals at the input/output of RF transmitter stages. (11% chose this)
  • Connect the radio to the SPECAN through an in-line attenuator, apply minimum attentuation and switch the radio to LOW power. Use an inductive probe to evaluate signals at the input/output of AF transmitter stages. (20% chose this)
  • Connect the radio to the SPECAN through an in-line attenuator, apply maximum attentuation and switch the radio to LOW power. Use an inductive probe to evaluate signals at the input/output of RF transmitter stages. (60% chose this)
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Which of the following test procedures may be used to determine a VHF receiver's minimum discernible signal?
  • Connect an oscilliscope to the antenna input and observe the amplitude of minimum signal voltage plotted on the display's vertical axis as a function of time on the horizontal axis. (14% chose this)
  • Set a signal generator to the frequency of the VHF receiver, adjust the output signal to near zero, and increase the signal level until an audio voltmeter connected to the AF output point indicates a 3-dB increase. (66% chose this)
  • Connect a spectrum analyzer to the antenna input and apply the maximum amount of attentuation to detect minimum signal level plotted on the display's vertical axis as a function of frequency on the horizontal axis. (16% chose this)
  • Connect a 156.3 Mhz signal generator to the antenna input, set the VHF receiver to channel 06 and measure dynamic range using an oscilliscope. (4% chose this)
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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?
  • The AGC circuit has failed. (17% chose this)
  • The BFO circuit has failed. (2% chose this)
  • The squelch circuit has failed. (62% chose this)
  • The AF amplifier circuit has failed. (19% chose this)
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What condition would cause an IP connection failure between a technician's laptop and an Inmarsat Fleet Broadband terminal?
  • The laptop settings are not compatible with the terminal's LAN port. (22% chose this)
  • The technician has disabled the Power over Ethernet (POE) function. (13% chose this)
  • The EIA-232 configuration is not compatible with the Inmarsat terminal. (4% chose this)
  • The technician has connected the Ethernet cable to the terminal's ISDN port. (61% chose this)
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What are the input/output voltages of a "BUCK" switching power supply with a 50% duty cycle?
  • 120 volts in, 240 volts out. (9% chose this)
  • 24 volts in, 36 volts out. (9% chose this)
  • 12 volts in, 12 volts out. (20% chose this)
  • 10 volts in, 5 volts out. (61% chose this)
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Power supplies with inductive input filters have the following characteristics:
  • Poor voltage regulation with high peak rectifier currents. (11% chose this)
  • Good voltage regulation with high transformer utilization factor. (61% chose this)
  • Low transformer utilization factor with low rectifier peak currents. (9% chose this)
  • High transformer utilization factor with high rectifier peak currents. (19% chose this)
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The characteristics of a 10:1 attenuation probe for an oscilloscope is as follows:
  • A load of about 10 megohms shunted by 12 pF. (67% chose this)
  • A load of about 20 megohms shunted by a 12 mH coil. (16% chose this)
  • A load of about 5 megohms shunted by 6 pF. (4% chose this)
  • A load of about 5 megohms shunted by a 6 mH coil. (12% chose this)
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How can a LES/RCC (Rescue Coordination Centre) determine if an Inmarsat-C Distress Alert is a TEST transmission?
  • A flag in the message is set to identify the transmission as a test alert. (65% chose this)
  • The validity of each Distress alert must be manually verified by LES/RCC personnel. (8% chose this)
  • A Distress acknowledgement is sent from the LES/RCC to the originating station. (12% chose this)
  • LES/RCC personnel cannot distinguish between valid and TEST transmissions. (16% chose this)
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Which of the following is true of SITOR (NBDP) ARQ mode:
  • The ship station sends a group of 3 characters twice and then waits for an "RQ" signal to indicate proper receipt before transmission of the next 3 characters. (19% chose this)
  • The Ship station sends each character twice, using a time diversity system to ensure proper parity. (15% chose this)
  • The ship station sends a group of 3 characters, the shore station checks for proper parity and then requests the same group be resent to enable error correction. (6% chose this)
  • The ship station sends a group of 3 characters, the shore station checks for proper parity. If parity is OK, the shore station indicates readiness for transmission of the next 3 characters. (61% chose this)
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Which of the following devices can cause interference to Fleet 77/55 systems?
  • 406 MHz Emergency Position Indicating Radio Beacons (EPIRBs) in the transmit mode. (10% chose this)
  • 9.3 GHz Search And Rescue RADAR Transponders (SARTs) in the transmit mode. (14% chose this)
  • Transmitters operating in the 3-30 MHz range and shipboard RADARS in close proximity. (68% chose this)
  • Survival Craft Equipment in the VHF range in the high power transmit mode. (8% chose this)
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What would be considered a normal sensitivity for 10 db of quieting in a VHF marine receiver?
  • 0.1 microvolt (15% chose this)
  • 1 microvolt (62% chose this)
  • 5 microvolts (16% chose this)
  • 10 microvolts (7% chose this)
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Which of the following is normally part of 406 MHz satellite EPIRBs?
  • A strobe light, automatic float-free bracket, 1-watt 406-MHz alert beacon. (27% chose this)
  • A 5-watt 406-MHz alert beacon, Automatic Hydrostatic Release (ARM), strobe light. (57% chose this)
  • Automatic float-free bracket, 5-watt 121.5 MHz homing beacon, strobe light. (13% chose this)
  • Automatic Hydrostatic Release (ARM), 1-watt 121.5 MHz alerting beacon, strobe light. (3% chose this)
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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?
  • 4.99 to 5.01 volts DC (61% chose this)
  • 4.98 to 5.02 volts DC (14% chose this)
  • 4.97 to 5.02 volts DC (9% chose this)
  • 4.95 to 5.05 volts DC (16% chose this)
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Which of the following statements about a logic probe is false?
  • A "Red" LED indicates a "High" state. (12% chose this)
  • Both "Red" and "Green" LEDs on indicate a short. (65% chose this)
  • A "Green" LED indicates a "Low" state. (8% chose this)
  • An "Amber" LED indicates a "pulse". (15% chose this)
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Selective FEC communications (SFEC) are employed when:
  • Multiple stations without a group SELCALL must receive communications without using their transmitters. (6% chose this)
  • Multiple stations must receive communications by using their transmitters to achieve phasing. (10% chose this)
  • An individual station must receive communications without transmitting (Radio Silence). (68% chose this)
  • An individual station must receive communications by using their transmitter to achieve phasing and block other stations from breaking in. (16% chose this)
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What is the assigned bandwidth and channel spacing for J3E voice transmissions?
  • 170 Hz and 300 Hz (4% chose this)
  • 300 Hz and 500 Hz (25% chose this)
  • 2.8 kHz and 3.0 kHz (64% chose this)
  • 3.1 kHz and 4.0 kHz (8% chose this)
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What condition may indicate a VHF receiver fault?
  • The same voltage reading between each lead of a 100K-ohm resistor and ground in a bias circuit. (59% chose this)
  • A "click" is heard when an ohmmeter set to R X 1 is touched across loudspeaker terminals. (10% chose this)
  • A voltage drop across the leads of a 47K ohm resistor in an intermediate frequency amplifier stage. (12% chose this)
  • The presence of an AC signal on the output of an audio frequency amplifier stage. (19% chose this)
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What is the allowable frequency tolerance for GMDSS MF-HF transmitters?
  • 10 Hz (63% chose this)
  • 15 Hz (20% chose this)
  • 20 Hz (13% chose this)
  • 30 Hz (4% chose this)
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An MF-HF transceiver works properly on voice but not SITOR (NBDP). What is the most likely source of the problem?
  • The 500 Hz I.F. filter has failed. (63% chose this)
  • The audio amplifier has failed. (2% chose this)
  • The phase locked loop circuit has failed. (22% chose this)
  • The R.F. amplifier has failed. (13% chose this)
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What characteristics are desirable in an AGC circuit for SSB voice reception?
  • Slow attack and decay. (5% chose this)
  • Slow attack and fast decay. (16% chose this)
  • Fast attack and decay. (18% chose this)
  • Fast attack and slow decay. (61% chose this)
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What is the best method for grounding an Inmarsat-C terminal?
  • Number 10 copper wire between terminal and the ship/s steel hull. (16% chose this)
  • A good ground at the antenna is sufficient. (13% chose this)
  • Copper strap brazed to the steel terminal and ship's steel hull. (62% chose this)
  • An aluminum strap bolted to both the steel terminal and ship's steel hull. (9% chose this)
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In dual-trace oscilloscopes the purpose of the "Mode" control is to:
  • Select a choice between DC or AC input on either channel. (20% chose this)
  • Select either channel alone or a combination of both channels. (62% chose this)
  • Select the proper time base of either channel. (7% chose this)
  • Select the proper frequency compensation for both channels. (11% chose this)
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What feature is not a component of a 406 MHz satellite EPIRB?
  • 121.5 MHz emergency homing transmitter. (26% chose this)
  • Emergency transmission on 406.025 MHz. (4% chose this)
  • Float-free release bracket. (11% chose this)
  • Aural locator signal. (60% chose this)
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What is the normal voltage of a single NICAD battery cell?
  • 1.2 volts (61% chose this)
  • 1.5 volts (7% chose this)
  • 2.1 volts (20% chose this)
  • 2.5 volts (13% chose this)
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How often must the Survival Craft Transceiver battery be changed?
  • 2 years or after use for distress communications. (32% chose this)
  • 3 years or after use for distress communications. (5% chose this)
  • 5 years or after use for distress communications. (58% chose this)
  • 8 years or after use for distress communications. (5% chose this)
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What condition may indicate voltage controlled oscillator failure in the synthesizer of a VHF transmitter?
  • Low transmitter power output in the high power mode. (4% chose this)
  • An out-of-lock condition in the Phased Locked-Loop circuit. (62% chose this)
  • Excessive deviation in the frequency modulated output signal. (29% chose this)
  • A constant transmitter power output at various modulation levels. (5% chose this)
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Which is not a function of a satellite under COSPAS-SARSAT using satellite EPIRBs?
  • After the EPIRB's position is calculated using the Doppler shift COSPAS-SARSAT satellites provide follow-on SAR communications. (58% chose this)
  • Relayed satellite message includes the EPIRB ID number which provides a reference for retrieval of vessel information from the shore database. (10% chose this)
  • Doppler shift of EPIRB signal is measured and the EPIRB's position is calculated. (5% chose this)
  • Information received from EPIRBs is time-tagged and transmitted to any Local User Terminal in the satellite's view. (27% chose this)
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What is a gel cell battery and how is it maintained & cared for?
  • Gel cell batteries are typically sealed — special charging rates and voltages may be required. (67% chose this)
  • Gel cell batteries are lead acid with a solid electrolyte — each cell is checked with a voltmeter. (8% chose this)
  • Gel cell batteries are NICAD with a solid electrolyte — each cell is checked with a voltmeter. (8% chose this)
  • Gel cell batteries are have special liquid electrolytes — they are charged with the NICAD charging rates and voltages. (17% chose this)
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What initial steps should be taken when installing a router?
  • Connect the router to your computer and boot up the router with the setup software. (25% chose this)
  • Open web browser, access the internet, enter username and password and download instructions. (8% chose this)
  • Open web browser, enter router's address for network admin and enter username and password. (66% chose this)
  • Connect the router to your computer and enter the addresses for all stations in the system. (2% chose this)
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What is the function of the "TUNE" button on a MF/HF transceiver?
  • To tune in a new ITU channel. (5% chose this)
  • To tune the frequency of the receiver. (27% chose this)
  • To tune the antenna to the transmit frequency. (64% chose this)
  • To tune the frequency of the AF amplifier. (4% chose this)
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A modulation index set to less than 1 to 1 may result in what?
  • Excessive deviation (16% chose this)
  • Unstable signal excursions (13% chose this)
  • Unusually low level transmit audio (63% chose this)
  • Unusually high pitch audio response (9% chose this)
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What are the disadvantages of using a switcher type power supply?
  • Increased complexity (more likelihood of a component failure), increased cost (many more parts) and tendency to create radiated AF. (23% chose this)
  • Increased complexity (more likelihood of a component failure), increased cost (many more parts) and tendency to create radiated RF. (61% chose this)
  • Decreased complexity (less likelihood of a component failure) and decreased cost (fewer parts and tendency to create radiated RF. (9% chose this)
  • Decreased complexity (less likelihood of a component failure) and decreased cost (fewer parts and tendency to create radiated AF. (7% chose this)
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What condition would cause a connection failure between a technician's laptop and an Inmarsat Fleet Broadband terminal?
  • The wrong IP address was entered as the URL in the web browser. (66% chose this)
  • The ASD function is enabled but the HSD function is disabled. (6% chose this)
  • The terminal's DTE port is set to the Asynchronous Data Service. (17% chose this)
  • The password for the High Speed Data service has been improperly entered. (11% chose this)
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What statement is true regarding the exchange between two stations engaged in SITOR (NBDP) communications?
  • In ARQ, each character is transmitted twice, with the second displaced in time from the first. (4% chose this)
  • In ARQ, the "sending" station transmits a block of three characters and the "receiving" station responds with a one character Repeat Request. Following this the "transmitting" station will send a new block. (19% chose this)
  • In ARQ, the ISS transmits a block of 3 characters and the IRS checks for parity. If the received block is correct a control signal is sent notifying the ISS to proceed. If the parity check fails the block must be resent. (67% chose this)
  • Broadcasts of Maritime Safety Information, traffic lists, etc. can be copied by the receiving station in ARQ mode. (10% chose this)
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What type of data communication is used for NMEA 0183.
  • Parallel (6% chose this)
  • Serial (71% chose this)
  • Can Bus (6% chose this)
  • Ethernet (16% chose this)
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The U.S. National Data Center that monitors polling input for each US Flag ship:
  • Must receive at least 4 position reports daily. (66% chose this)
  • Must receive LRIT position reports each hour. (9% chose this)
  • Must receive at least 1 position report daily including the number of crew aboard. (21% chose this)
  • Is a double check on AIS output. (4% chose this)
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What is the most important factor when locating depth finder transducers?
  • In an area not subject to cavitation. (63% chose this)
  • They must be equidistant from the bow and the stern. (5% chose this)
  • They must be on the centerline of the ship. (18% chose this)
  • They should be as close to the bow as possible. (14% chose this)
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10Base-T and 100Base-TX systems generally uses the following type of cable:
  • CAT-5 with 2 twisted pairs (10% chose this)
  • CAT-5 with 4 twisted pairs (72% chose this)
  • Coax (16% chose this)
  • Fiber optic (2% chose this)
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What type of signals are usually provided by a simple Function Generator?
  • Sine Waves with pulse modulation. (16% chose this)
  • Sine Waves and Square Waves. (14% chose this)
  • Square Waves and Triangular Waves. (9% chose this)
  • Sine Waves, Square Waves and Triangular Waves. (62% chose this)
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Which of the following statements concerning SITOR (NBDP) communications is true?
  • In ARQ, each character is transmitted twice, about 250 milliseconds apart. (6% chose this)
  • In ARQ, the "information sending station" will transmit a block of three characters that the receiving station will subsequently acknowledge or request it to be retransmitted. (71% chose this)
  • In ARQ, the "information sending station" transmits a block of three characters twice, about 250 milliseconds apart. (14% chose this)
  • SITOR communications can be used to contact a NAVTEX transmitting station when requesting a repeat transmission of a missed NAVTEX message. (10% chose this)
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What is the purpose of the BFO?
  • Re-injects the carrier frequency in the receiver's detector to demodulate the SSB signal. (71% chose this)
  • Replace the missing sideband and carrier frequency. (12% chose this)
  • Remove the carrier from H3E transmissions. (4% chose this)
  • Inverts the SSB signal to remove interference. (14% chose this)
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What must a LRIT terminal do?
  • Capable of being configured to automatically transmit an APR, transmit an APR every 6 hours, be able to automatically transmit a PR if requested. (69% chose this)
  • Capable of being configured to automatically transmit an APR, transmit an APR every 12 hours, be able to automatically transmit a PR if requested. (12% chose this)
  • Capable of being configured to automatically receive an APR, transmit an APR every 8 hours, be able to automatically transmit a PR if requested. (12% chose this)
  • Capable of being configured to automatically receive an APR, transmit an APR every 24 hours, be able to automatically transmit a PR if requested. (8% chose this)
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Nodes in an Ethernet network are interconnected using a cable making a "Home Run"back to the central:
  • Router (27% chose this)
  • Backbone (5% chose this)
  • Computer (10% chose this)
  • Hub (58% chose this)
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What satellite system does not support LRIT?
  • Inmarsat-C (9% chose this)
  • GPS (65% chose this)
  • IRIDIUM (13% chose this)
  • Inmarsat-D+ (13% chose this)
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What is the usual arrangement of GPS satellites?
  • 18 satellites in 3 orbital planes, 6 satellites in each plane, 23,400 km altitude and 55 degrees inclination. (8% chose this)
  • 24 satellites in 6 orbital planes, 4 satellites in each plane, 20,200 km altitude and 55 degrees inclination. (73% chose this)
  • 30 satellites in 5 orbital planes, 6 satellites in each plane, 20,200 km altitude and 60 degrees inclination. (2% chose this)
  • 36 satellites in 6 orbital planes, 6 satellites in each plane, 23,600 km altitude and 60 degrees inclination. (16% chose this)
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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?
  • You must RESET the DSC memory by holding down two buttons as described in the user manual. (24% chose this)
  • You can never change a number, once one is already programmed. (4% chose this)
  • Re-register the old MMSI with the new owner and make no programming changes to the radio. (6% chose this)
  • Contact the manufacturer for action to clear the MMSI memory and accept the new number. (67% chose this)
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What would be an indication of a malfunction on a GMDSS station with a 24 VDC battery system?
  • All of these symptoms would indicate a potential battery charger malfunction. (13% chose this)
  • A constant 30 volt reading on the GMDSS console voltmeter. (69% chose this)
  • After testing the station on battery power, a voltmeter reading of 30 volts for a brief period followed by a steady 26 volt reading. (12% chose this)
  • After testing the station on battery power, the ammeter reading indicates a high rate of charge that then declines. (6% chose this)
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A masthead antenna with a base loading coil appears shorted to an ohmmeter check. What might this indicate?
  • Positive proof of shorted coaxial cable plugs. (12% chose this)
  • May be normal for a well working shunt fed antenna system. (71% chose this)
  • Immediately repair both upper and lower PL-259s. (6% chose this)
  • No VHF antenna should measure a short circuit.   (12% chose this)
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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?
  • The transmitter of the abnormal signal is off frequency. (70% chose this)
  • The receiver frequency synthesizer circuit is defective. (17% chose this)
  • The voltage controlled oscillator has failed. (8% chose this)
  • The B.F.O. circuit is faulty. (6% chose this)
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You are able to hear signals in the voice/SSB mode but not in the SITOR (NBDP) mode. What is the most likely cause?
  • The phase locked loop circuit has failed. (20% chose this)
  • The 500 Hz I.F. filter has become defective. (66% chose this)
  • The R.F. amplifier has failed. (5% chose this)
  • The B.F.O. circuit has failed. (9% chose this)
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Which of the following connectors is often used in GMDSS MF/HF antenna systems?
  • "F" Connector (6% chose this)
  • "SMA" Connector (14% chose this)
  • "EIA-232" Connector (6% chose this)
  • "PL-259" Connector (74% chose this)
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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?
  • Rig a wire antenna 10 ft long from the antenna tuner to the highest vertical support. (13% chose this)
  • Rig a horizontal, center-fed dipole antenna 10 ft long to the antenna tuner. (11% chose this)
  • Rig a wire antenna approximately 35-40 ft long per the equipment instruction manual. (70% chose this)
  • Connect the MF/HF transceiver to the VHF antenna. (6% chose this)
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What are the characteristics of the SART transmitted signal?
  • It starts with a sweep of 10.2 usec.followed by a sweep of 0.6 usec for a total of 10 sweeps. (8% chose this)
  • It starts with a sweep of 0.8 usec followed by a sweep of 12.6 usec for a total of 12 sweeps. (20% chose this)
  • It starts with a sweep of 0.4usec across the entire 3 cm radar band followed by a returning sweep of 7.5 usec back to the beginning for a total of 12 sweeps. (63% chose this)
  • It starts with a sweep of 8.5 usec followed by a sweep of 0.4 usec for 10 sweeps. (8% chose this)
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What is the normal voltage of a single lead acid battery cell?
  • 1.5 volts (13% chose this)
  • 2.1 volts (69% chose this)
  • 2.5 volts (17% chose this)
  • 2.8 volts (2% chose this)
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What is the correct modulation rate and index of modulation for VHF-DSC?
  • 800 baud, 3.0 +/- 10% (7% chose this)
  • 1200 baud, 2.0 +/- 10% (65% chose this)
  • 1500 baud, 2.0 +/- 5% (16% chose this)
  • 1800 baud, 3.0 +/- 5% (12% chose this)
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Which of the following conditions would prevent communications between an Inmarsat-C data port and external data terminal equipment (DTE)?
  • Use of a stop bit in the DCE/DTE communication parameters. (13% chose this)
  • Grounding pin 5 of the standard EIA-232 connector. (13% chose this)
  • Use of a "0" parity bit in the DCE/DTE communication parameters. (12% chose this)
  • Use of a "null" MODEM cable to connect the DTE device. (62% chose this)
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Which of the following is NOT a required VHF test during an annual inspection?
  • Carrier deviation measurement. (64% chose this)
  • Power output and VSWR on Channels 6, 13 and 16. (17% chose this)
  • Equipment is within frequency tolerance. (9% chose this)
  • Equipment operates from all required power sources. (10% chose this)
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If you are listening to another vessel's HF transmission and it sounds garbled what should you do?
  • Change the receive frequency to either adjacent channel. (6% chose this)
  • Advise the other vessel that his transmission is faulty. (7% chose this)
  • Use the "R.I.T." or "Clarifier" control to adjust the frequency of the receiver. (70% chose this)
  • Adjust the squelch control to clear up the sound quality. (17% chose this)
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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?
  • Tune the VHF receiver to 158.6 MHz and listen for local U.S. Coast Guard announcements or radio traffic from other vessels. (19% chose this)
  • Set the VHF radio to a simplex channel, key the transmitter, and monitor the quality of the transmitted signal with the internal receiver. (9% chose this)
  • Tune the VHF radio to 162.550 MHz, 162.400 MHz or 162.475 MHz and listen for broadcasts from the National Oceanic and Atmospheric Administration. (66% chose this)
  • Connect appropriate test equipment to the radio and measure signal levels at the output of the receiver's RF amplifier stage. (7% chose this)
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An important difference between NMEA 0183 and NMEA 2000 is:
  • Relay switched vs diode switch (10% chose this)
  • Low voltage vs high voltage (10% chose this)
  • Single talker vs multi-talkers (75% chose this)
  • Data transfer vs video transfer (6% chose this)
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Which of the following best describes a standard full wave rectifier power supply?
  • It uses a capacitor input filter to provide good voltage regulation. (28% chose this)
  • It must only use a single diode rectifier. (6% chose this)
  • The ripple frequency is twice the input frequency. (59% chose this)
  • It must always use a center tapped transformer secondary. (6% chose this)
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How is the lower sideband eliminated?
  • By using a double balanced mixer to block the lower sideband. (18% chose this)
  • By using a filter to pass the lower sideband and block the upper sideband. (11% chose this)
  • By using a double balanced mixer to insert the carrier. (4% chose this)
  • By using a filter to pass the upper sideband and block the lower sideband. (68% chose this)
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What is an LNA?
  • Line noise amplifier (11% chose this)
  • Low number algorithm (9% chose this)
  • Low noise antenna (8% chose this)
  • Low noise amplifier (72% chose this)
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When a compulsory equipped IMO ship is not correctly broadcasting LRIT Info what action should be taken?
  • Check the power fuse on the Sat D box located on the bridge. (9% chose this)
  • Can re-boot the AIS broadcasting unit. (6% chose this)
  • Verify the Ship Security Alerting System has not been accidentally activated. (13% chose this)
  • Double check the GMDSS Console's Inmarsat-C terminal for regular operation. (72% chose this)
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What is meant by "full quieting" in a FM VHF receiver?
  • Adjusting the squelch control to eliminate background noise. (24% chose this)
  • The rapid decrease in SINAD and noise with increasing signal level. (7% chose this)
  • The received signal is strong enough to completely quiet the receiver background noise. (64% chose this)
  • The rapid improvement in SINAD and decrease in noise with decreasing signal level. (5% chose this)
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What is the most important consideration for installing a Full-Duplex VHF radiotelephone.
  • Maximum separation between the transmitter and receiver. (12% chose this)
  • Minimum separation between transmitting antennas. (9% chose this)
  • Maximum separation between transmitting antennas. (12% chose this)
  • Maximum separation between transmitting antenna and the duplex receiver antenna. (67% chose this)
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What type of code is used for DSC transmissions?
  • A 7 bit code with a constant ratio of 4/3 between the 1s and 0s. (21% chose this)
  • A 7 bit code followed by an error check character at the end. (5% chose this)
  • A 10 bit code followed by an error check character at the end. (5% chose this)
  • A 10 bit code with 7 bits used for information and 3 bits used for error correction. (68% chose this)
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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.
  • The antenna may be defective or water intrusion has affected antenna system performance. (14% chose this)
  • The coaxial transmission line may be open, shorted, or a connector has become intermittent. (9% chose this)
  • A fault in the discriminator circuit is producing zero output voltage during peak modulation. (9% chose this)
  • A "crowbar" circuit has prevented an over current condition that might damage the radio. (68% chose this)
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What function does the LNA perform?
  • Receives and amplifies a very weak signal from the satellite. (75% chose this)
  • Calculates data received. (6% chose this)
  • Increases the receiver's noise figure. (10% chose this)
  • Provides degenerative feedback to the LNB. (10% chose this)
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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?
  • Defective coax cable. (13% chose this)
  • Faulty antenna control module. (65% chose this)
  • Bad I.F. amplifier. (5% chose this)
  • Bad Gyro repeater motor. (17% chose this)
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What is the function of a crowbar circuit?
  • It provides a voltage reference for the voltage regulator. (6% chose this)
  • It prevents an overvoltage condition from damaging circuitry by shorting the power supply output. (75% chose this)
  • It provides a voltage reference for the chopper circuit. (15% chose this)
  • It provides a feedback signal for the chopper circuit. (4% chose this)
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What condition may exist if a VHF radio is operational in receive mode but unable to transmit?
  • Excessive bias is being applied to switching transistors in the transmitter output stage. (9% chose this)
  • The solid-state antenna relay is no longer functioning properly. (2% chose this)
  • A component in the Push-To-Talk (PTT) circuit has failed. (71% chose this)
  • The SWR protection circuit has engaged to prevent transmission. (18% chose this)
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At what interval must the SART's battery be replaced?
  • Every 2 years. (7% chose this)
  • Every 3 years or after being used. (22% chose this)
  • Every 5 years or after being used. (71% chose this)
  • Every 8 years. (0% chose this)
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What fault may exist if a VHF radio receiver fails to produce audible output from the speaker and the squelch control has no effect?
  • A component in the RF amplifier stage has failed or the signal from a preceding stage is grounded. (14% chose this)
  • The Local Oscillator stage is no longer supplying a signal to the mixer stage at the correct frequency. (8% chose this)
  • The AF amplifier may be defective or the transmitter Push-To-Talk circuit may be activated. (66% chose this)
  • The mixer stage is no longer producing an output signal on the correct Intermediate Frequency (IF). (12% chose this)
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Which of the following is the best procedure to test the Inmarsat Distress Alarm?
  • Lift the plastic cover and depress the "DISTRESS" button. (5% chose this)
  • Advise the US Coast Guard you are going to test the Distress Alarm. (19% chose this)
  • Use service number 33 to arrange a Distress Alarm test transmission with the LES in advance. (67% chose this)
  • Broadcast a SAFETY priority call to all stations immediately prior to initiating the Distress Alarm. (9% chose this)
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What are the major components of a phase locked loop frequency synthesizer?
  • Ratio detector, master oscillator, limiting amplifier and voltage controlled oscillator. (11% chose this)
  • Phase comparator, loop filter, master oscillator and first mixer stage. (11% chose this)
  • High pass filter, master oscillator, double balanced mixer and voltage controlled oscillator. (7% chose this)
  • Master oscillator, frequency dividers, phase comparator, loop filter and voltage controlled oscillator. (71% chose this)
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Which in-line RF power reading indicates the proper operation of a VHF marine transmitter?
  • 25 watts forward/1.5 watts reflected. (76% chose this)
  • 25 watts forward/25 watts reflected. (12% chose this)
  • 27.5 watts forward/1.5 watts reflected. (6% chose this)
  • 2.5 watts forward/1.5 watts reflected. (6% chose this)
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What is the abbreviation for signal to noise?
  • STN (7% chose this)
  • SIG/NR (13% chose this)
  • SNR (74% chose this)
  • SIN (6% chose this)
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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?
  • A defective coaxial cable connecting the terminal to the antenna. (11% chose this)
  • The failure of an I.F. amplifier stage in the terminal's receiver. (9% chose this)
  • A component failure within the power supply itself. (74% chose this)
  • A defective video monitor connected to the Inmarsat-C terminal. (6% chose this)
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What is the electrical effect of an inductance in series with the antenna?
  • It electrically lengthens a physically fixed length antenna. (73% chose this)
  • It electrically shortens a physically fixed length antenna. (15% chose this)
  • It raises the resonant frequency of a physically fixed length antenna. (7% chose this)
  • It increases the bandwidth of a physically fixed length antenna. (5% chose this)
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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?
  • Insert an in-line RF Power meter between the VHF radio and an artificial antenna, set the radio to any channel, key the microphone, and read the measured value. (6% chose this)
  • Insert a SWR meter between the VHF transmitter and the coaxial transmission line connected to the antenna, set the radio to channel 16, and conduct a "RADIO CHECK" with a nearby U.S. Coast Guard station or vessel. (11% chose this)
  • Insert an in-line RF Power meter between the VHF radio and the coaxial transmission line disconnected from the antenna, activate the Push-To-Talk (PTT) circuit, and read the forward and reflected values. (9% chose this)
  • Insert a SWR meter between the VHF radio and the coaxial transmission line connected to the antenna, set the radio to an unused channel, activate the Push-To-Talk (PTT) circuit, and read the measured value. (74% chose this)
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Bridge equipment separation recommendations generally refer to what instrument?
  • GPS (6% chose this)
  • Magnetic compass (75% chose this)
  • ECDIS (11% chose this)
  • Auto Pilot (8% chose this)
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What is signal to noise ratio?
  • A measure used that compares the distance of a desired signal to the level of background noise. (14% chose this)
  • A measure used that compares the level of a desired signal to the level of background noise. (70% chose this)
  • A measure used that compares the frequency of a desired signal to the frequency of background noise. (9% chose this)
  • A measure that measures signal in the forward direction and noise in the reverse direction. (7% chose this)
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Which of the following are NOT components of a NMEA 2000 network?
  • Tees, Drop Cables and terminating Resistors. (11% chose this)
  • Tees, Backbone Cables, Power Cables. (6% chose this)
  • Termination Resistors, Power Cables, Backbone Cables. (9% chose this)
  • Multiplexers, Combiners, Routers. (74% chose this)
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Power is on but the computer will not boot into the operating system. What steps should you take?
  • Make sure the CPU fan is operating normally. (0% chose this)
  • Remove the network driver card, clean contacts and reinsert. (2% chose this)
  • Remove all external cables and try again. (20% chose this)
  • Use the BIOS setup mode to check for proper BIOS settings. (78% chose this)
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Which of the following is not one of the main advantages of a switching power supply?
  • Works with a wide range of input voltages. (8% chose this)
  • Can work with direct current input. (18% chose this)
  • No RFI problems. (61% chose this)
  • Lighter weight than linear power supplies. (14% chose this)
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Which of the following best describes a Subscriber Identity Module (SIM)?
  • A removable device to implement Inmarsat digital rights management (DRM). (9% chose this)
  • A non-volatile device to implement high-speed data and other advanced terminal features. (7% chose this)
  • An integrated circuit device that securely stores the Inmarsat identity and an authentication key. (73% chose this)
  • A Read/Write data device that uses x.25 protocol to limit terminal access to authorized users. (11% chose this)
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What is the purpose of the "R.I.T." control on a MF/HF transceiver?
  • Make slight adjustments to the transmit frequency. (20% chose this)
  • Make slight adjustments in the receiver frequency. (73% chose this)
  • Select the proper transmitter emissions. (5% chose this)
  • Select the proper paired duplex channel. (2% chose this)
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What are the most commonly used IP addresses for routers?
  • 198.162.1.1, 196.168.1.1 and 196.166.1.1 (15% chose this)
  • 194.166.1.0, 194.166.1.1 and 194.168.1.2 (0% chose this)
  • 192.168.1.1, 192.168.0.1 and 192.168.2.0 (74% chose this)
  • 192.166.1.0, 192.166.1.1 and 192.164.2.0 (11% chose this)
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Which of the following actions should be taken to minimize shock hazard of an Inmarsat terminal?
  • Ensure the DC power supply is insulated from the ship's hull. (8% chose this)
  • Ensure the chassis of the Inmarsat terminal is connected to an electrical ground. (77% chose this)
  • Install a common busbar for grounding to ensure common-mode coupling. (10% chose this)
  • Isolate the transceiver's metal frame to avoid a return path for fault currents. (6% chose this)
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In what frequency band does a search and rescue transponder operate?
  • 9 GHz (69% chose this)
  • 3 GHz (8% chose this)
  • S-band (5% chose this)
  • 406 MHz (17% chose this)
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How is the GPS usually interconnected with other bridge equipment?
  • Through a 8-bit parallel line network. (7% chose this)
  • Through a USB port. (7% chose this)
  • Through an Ethernet LAN. (9% chose this)
  • Through a NMEA-0183 or NMEA-2000 LAN. (76% chose this)
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What condition may prevent a VHF radio receiver from staying tuned to the desired channel?
  • The local oscillator frequency is beating against the incoming signal to produce an Intermediate Frequency (IF). (11% chose this)
  • The output signal of the Phase Locked Loop (PLL) circuit in the frequency synthesizer has become unlocked. (72% chose this)
  • The discriminator circuit is alternately developing positive and negative voltages at the modulation frequency. (9% chose this)
  • The ratio detector circuit is producing a variable output that deviates across the receiver's dynamic range. (9% chose this)
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How might a DSC radio check be accomplished with a coast station?
  • Enter the station's MMSI, and press the button under the red plastic cover for 5 seconds. (4% chose this)
  • Select DSC menu item TEST, enter the Coast Station's FCC call letters, and send the test call. (19% chose this)
  • Select DSC menu item TEST, enter the Coast Station's MMSI number, and send the test. (76% chose this)
  • Select DSC menu ALL SHIPS, and send the test message. (2% chose this)
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What type of coaxial cable would be most appropriate for a long transmission line run?
  • "RG-58/U" (11% chose this)
  • "RG-59/U" (11% chose this)
  • "RG-8/U" (73% chose this)
  • "RG-174/U" (5% chose this)
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How is a NAVTEX receiver programmed to reject certain messages?
  • The transmitting station's two-digit identification can be entered to de-select reception of its broadcasts. (13% chose this)
  • By entering the SELCALL of the transmitting station. (4% chose this)
  • By pressing "00" in the transmitter's ID block. (6% chose this)
  • By choosing a message category's single letter (A-Z) identifier and then deselecting or deactivating. (77% chose this)
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What is the purpose of a deviation meter?
  • Measure the number of sidebands. (2% chose this)
  • Measure the modulation index. (15% chose this)
  • Measure the carrier deviation in an FM transmitter. (76% chose this)
  • Measure the carrier frequency. (7% chose this)
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What battery tests are made during the annual inspection?
  • Record the specific gravity of all cells while the batteries are charging. (5% chose this)
  • The terminal voltage is measured and recorded at the end of a 6 hour full load discharge. (13% chose this)
  • Record the specific gravity of all cells while the batteries are discharging. (5% chose this)
  • With battery off charge and maximum required load measure and record maximum discharge current and voltage. (76% chose this)
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What is the maximum allowable deviation of a marine VHF transmitter?
  • 12 kHz (5% chose this)
  • 10 kHz (17% chose this)
  • 7.5 kHz (8% chose this)
  • 5 kHz (70% chose this)
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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?
  • 1.375 Voltmeter (0% chose this)
  • 1.180 Voltmeter (12% chose this)
  • 1.210 Hydrometer (18% chose this)
  • 1.280 Hydrometer (70% chose this)
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What are the operator's license requirements for conducting a GMDSS ship station annual inspection?
  • GMDSS Radio Operator's License. (10% chose this)
  • GMDSS Maintainer's License. (72% chose this)
  • First Class Radiotelegraph Operator's License. (7% chose this)
  • General Radiotelephone Operator's License. (10% chose this)
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Which statement is NOT true regarding the requirements of survival craft portable two-way VHF radiotelephone equipment?
  • Watertight to a depth of 1 meter for 5 minutes. (13% chose this)
  • Operates simplex on Ch-70 and at least one other channel. (78% chose this)
  • Effective radiated power should be a minimum of 0.25 Watts. (6% chose this)
  • The antenna is fixed and non-removable. (4% chose this)
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Which of the following coaxial cables is suitable for use in GMDSS MF/HF antenna systems?
  • RG-59, 72 ohm Coax (4% chose this)
  • RG-6, 72 ohm Coax (12% chose this)
  • RG-8, 50 ohm Coax (83% chose this)
  • RG-179, 75 ohm Coax (2% chose this)
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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?
  • Dummy load, artificial antenna. (77% chose this)
  • Phantom Antenna, dummy load. (11% chose this)
  • Isotropic suppressor, artificial antenna. (5% chose this)
  • Artificial attenuator, dummy load. (7% chose this)
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What is the time diversity reception interval for a VHF-DSC call?
  • 33-1/3 milliseconds (75% chose this)
  • 40.5 milliseconds (11% chose this)
  • 66-2/3 milliseconds (9% chose this)
  • 91 milliseconds (5% chose this)
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What mode is a MF/HF transceiver operating in when "TLX" displayed?
  • SITOR (NBDP) (73% chose this)
  • SSB (12% chose this)
  • DSC (12% chose this)
  • AM (3% chose this)
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What may happen if the USA-INT control is left on INT when in U.S. waters?
  • Your signals will be heard but other station replies will not be heard on certain channels. (75% chose this)
  • You will be able to communicate with public correspondence stations on Channel 5. (5% chose this)
  • Other stations will not be able to hear your transmissions and you will not hear any signals. (18% chose this)
  • You will not be able to operate on channel 13. (2% chose this)
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Reducing the "RF Gain" control on an MF/HF transceiver has what effect?
  • Reduces degenerative feedback to the RF amplifier stage. (11% chose this)
  • Reduces volume in response to a varying RF signal input. (5% chose this)
  • Reduces coupling between the receiver's RF amplifier stages. (7% chose this)
  • Reduces sensitivity of the RF amplifier stage. (77% chose this)
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What are important considerations when replacing a CD-ROM drive?
  • The speed must be identical to the drive it is replacing. (0% chose this)
  • The replacement drive should use the same interface system as the old drive. (90% chose this)
  • The amount of RAM in the replacement unit must match the old drive. (4% chose this)
  • The rate of data transfer must match the old drive. (6% chose this)
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What is the effect of temperature on the specific gravity of lead acid batteries?
  • Higher temperature results in a higher specific gravity reading. (10% chose this)
  • Higher temperature results in a lower specific gravity reading. (74% chose this)
  • Temperature has no effect on the specific gravity reading. (10% chose this)
  • Lower temperature results in a lower specific gravity reading. (5% chose this)
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What condition can indicate a communication failure between the second receiver (RX2) and the Antenna Control Unit (ACU) in an Inmarsat Fleet 77 terminal?
  • The terminal will indicate RX2 is locked onto a signal on the Inmarsat NCSC channel. (10% chose this)
  • The terminal will indicate receipt of a valid frame on the Inmarsat NCSC channel. (3% chose this)
  • The message "RX2 Comm error" or "ACU Comm error" will be displayed. (74% chose this)
  • The DCE/DTE communication protocol is improperly configured. (12% chose this)
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What causes the SART to begin a transmission?
  • When activated manually, it begins radiating immediately. (3% chose this)
  • After being activated the SART responds to RADAR interrogation. (73% chose this)
  • It is either manually or water activated before radiating. (17% chose this)
  • It begins radiating only when keyed by the operator. (7% chose this)
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Equipment for radiotelephony use in survival craft stations under GMDSS must have what characteristics?
  • Permanently-affixed antenna, watertight, power 1W or 25W. (8% chose this)
  • Watertight, power a minimum of 1W, operation on CH-16, Ch-13 & Ch-70. (6% chose this)
  • Operation on Ch-16, watertight, permanently-affixed antenna. (69% chose this)
  • Operation on Ch-16, Ch-13 & Ch-70, power 1W, permanently-affixed antenna. (16% chose this)
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What is the minimum number of satellites that must be received to provide the highest accuracy?
  • Four (83% chose this)
  • Two (8% chose this)
  • Eight (2% chose this)
  • Six (8% chose this)
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What will cause an individual battery cell to reverse polarity?
  • The charging circuits are connected in the correct polarity but all of the cells are equally charged. (7% chose this)
  • High discharge rates without allowing for a cool down period. (14% chose this)
  • When discharging the battery — if a cell becomes weaker then the remaining cells the discharge current will effectively charge the weaker cell in reverse polarity. (75% chose this)
  • Insufficient charging which does not bring all of the cells up to full charge. (4% chose this)
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What is the meaning of "Reserve Source of Energy"?
  • High caloric value items for lifeboat, per SOLAS regulations. (2% chose this)
  • Diesel fuel stored for the purpose of operating the powered survival craft for a period equal to or exceeding the U.S.C.G. and SOLAS requirements. (6% chose this)
  • Power to operate the radio installation and conduct Distress and Safety communications in the event of failure of the ship's main and emergency sources of electrical power. (90% chose this)
  • The diesel fueled emergency generator that supplies AC to the vessel's Emergency power bus. (2% chose this)
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What is the purpose of the "ENTER" function.
  • To store any incoming DSC message in memory. (9% chose this)
  • To recall any previously received message. (4% chose this)
  • To transmit a DSC distress alert. (4% chose this)
  • To accept the previous selection or data input. (83% chose this)
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Which of the following conditions would be a symptom of malfunction in a 2182 kHz SSB radiotelephone?
  • No indication of power output when speaking into the microphone. (79% chose this)
  • Much higher noise level observed during daytime operation. (4% chose this)
  • When testing a radiotelephone alarm on 2182 kHz into an artificial antenna, the Distress frequency watch receiver becomes un-muted, an improper testing procedure. (9% chose this)
  • Failure to contact a shore station 600 nautical miles distant during daytime operation. (9% chose this)
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Interference induced from nearby HF transmitters may cause Inmarsat system failures. What is the most appropriate action to resolve this problem?
  • Install a longer ground lead to the INMARSAT terminal. (4% chose this)
  • Install a low-pass filter between the coax cable and antenna. (11% chose this)
  • Reduce bias to the INMARSAT antenna's Low Noise Amplifier. (4% chose this)
  • Install ferrite clamps on the coax cable to suppress induced RF. (81% chose this)
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Which of the following is the primary frequency that is used exclusively for NAVTEX broadcasts internationally?
  • 490 kHz (5% chose this)
  • 518 kHz (75% chose this)
  • 2187.5 kHz (17% chose this)
  • 4209.5 kHz (3% chose this)
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 Which of the following best describes a VHF collinear array?
  • An antenna with phased elements, omni directional radiation pattern, offering up to 9 db gain. (86% chose this)
  • The cascade filters in the VHF radio's IF section. (6% chose this)
  • A shoreside directional VHF yagi antenna. (8% chose this)
  • A depth sounder phased array transducer. (0% chose this)
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What fault may exist if a VHF radio receiver fails to produce audible output from the speaker and the squelch control has no effect?
  • The AF amplifier may be defective or the transmitter Push-To-Talk circuit may be activated. (76% chose this)
  • A component in the RF amplifier stage has failed or the signal from a preceding stage is grounded. (7% chose this)
  • The Local Oscillator stage is no longer supplying a signal to the mixer stage at the correct frequency. (14% chose this)
  • The mixer stage is no longer producing an output signal on the correct Intermediate Frequency (IF). (3% chose this)
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Which of the following controls is not found on a VHF-DSC transceiver?
  • "Distress" (7% chose this)
  • "Cancel" (10% chose this)
  • "Squelch" (10% chose this)
  • "R.I.T." (74% chose this)
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A typical PC program that is used widely for logging and troubleshooting NMEA 0183 data is:
  • Excel (10% chose this)
  • Windows Explorer (4% chose this)
  • HyperTerminal (87% chose this)
  • Microsoft Word (0% chose this)
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Which of the following is the best test procedure to isolate the source of distortion in the audio output of a receiver?
  • Use an oscilloscope to visually display AC signals on the output of each AF amplifier stage. (68% chose this)
  • Use a spectrum analyzer to visually display the amplitude and frequency of each AF amplifier stage input. (15% chose this)
  • Use a signal generator to inject a 1 KHz signal into the first AF amplifier stage and evaluate audio output. (11% chose this)
  • Use a digital voltmeter to measure transistor bias voltages in each AF amplifier stage. (6% chose this)
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What is a best practice for installing Inmarsat satellite antennas aboard ship?
  • Install antennas as high as practical, free from shadowing of structures. (90% chose this)
  • Install antennas next to other Inmarsat antennas, away from structures. (6% chose this)
  • Connect the antenna to transmission line with the highest characteristic impedance. (4% chose this)
  • Install an inline filter with the transmission line to attenuate frequencies above 1 GHz. (0% chose this)
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What is the function of an "AGC" button?
  • To maintain a relatively constant AF output when the input signal varies. (80% chose this)
  • To reduce AF output when the input signal becomes weak. (4% chose this)
  • To increase the gain of the RF amplifier when the input signal is strong. (16% chose this)
  • To increase RF output when the input signal becomes strong. (0% chose this)
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What protocol can be used in connecting a PC to the LAN interface of an Inmarsat terminal?
  • ISDN (7% chose this)
  • SMTP (5% chose this)
  • TCP/IP (81% chose this)
  • FTP (7% chose this)
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What are the correct VHF Channels and Frequencies for Calling/Distress, DSC and bridge-to-bridge operations?
  • Ch-16, 156.800 MHz, Ch-70, 156.525 MHz and Ch-13, 156.650 MHz. (75% chose this)
  • Ch-06, 156.300 MHz, Ch-16, 156.800 MHz and Ch-13, 156.650 MHz. (13% chose this)
  • Ch-08, 156.400 MHz, Ch-70, 156.525 MHz and Ch-16, 156.800 MHz. (10% chose this)
  • Ch-06, 156.300 MHz, Ch-12, 156.600 MHz and Ch-13, 156.650 MHz. (2% chose this)
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What is the purpose of the USA-INT switch?
  • To provide for simplex operations with European Public Correspondence stations. (5% chose this)
  • To provide for duplex operations with U.S. Public Correspondence stations. (7% chose this)
  • To change from duplex to simplex operation on designated channels in European waters. (10% chose this)
  • To change from duplex to simplex operation on designated channels in U.S. waters. (78% chose this)
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Equipment for radiotelephony use in survival craft stations under GMDSS must have what capability?
  • Operation on 457.525 MHz. (4% chose this)
  • Operation on Ch-16. (85% chose this)
  • Operation on 121.5 MHz. (7% chose this)
  • Operation on Ch-70. (4% chose this)
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Which of the following is true of SITOR (NBDP) Mode B (FEC), in the presence of static crashes.
  • Data flow rate depends on signal propagation. (10% chose this)
  • Idle characters are sent upon request. (0% chose this)
  • Transmitter and receiver cannot synchronize. (10% chose this)
  • FEC reduces the error rate by transmitting each character twice. (79% chose this)
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It becomes necessary to construct a temporary VHF marine antenna. What should be the approximate length of the antenna?
  • 10 inches (6% chose this)
  • 12 inches (5% chose this)
  • 15 inches (13% chose this)
  • 18 inches (76% chose this)
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NAVTEX broadcasts are sent:
  • In categories of messages indicated by a single letter or identifier. (82% chose this)
  • Immediately following traffic lists. (11% chose this)
  • On request of maritime mobile stations. (2% chose this)
  • Regularly, after the radiotelephone silent periods. (5% chose this)
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How should the signal from a Search And Rescue RADAR Transponder appear on a RADAR display?
  • A series of dashes. (2% chose this)
  • A series of spirals all originating from the range and bearing of the SART. (13% chose this)
  • A series of twenty dashes. (0% chose this)
  • A series of 12 equally spaced dots. (85% chose this)
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What is the proper adjustment of the squelch control for maximum sensitivity?
  • Maximum clockwise rotation. (3% chose this)
  • Maximum counterclockwise rotation. (13% chose this)
  • Just below the point where the noise breaks through. (76% chose this)
  • The squelch has no effect on the sensitivity. (8% chose this)
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Which of the following transmitter power levels are permitted by FCC rules?
  • Low Power: 0.1 W, High Power: 5 W (4% chose this)
  • Low Power: 0.5 W, High Power: 25 W (9% chose this)
  • Low Power: 1 W, High Power: 25 W (71% chose this)
  • Low Power: 5 W, High Power: 50 W (16% chose this)
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What is the purpose of the antenna tuner?
  • Minimizes the carrier output. (2% chose this)
  • Maximizes the sidebands. (4% chose this)
  • Provides for maximum VSWR. (6% chose this)
  • Match the antenna to the operating frequency. (89% chose this)
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What is the easiest way to test the Inmarsat-C terminal for proper operation?
  • Send a brief test message to your own terminal. (89% chose this)
  • Contact the nearest RCC for a signal report. (6% chose this)
  • Contact the nearest ship for a signal report. (4% chose this)
  • Use the internal POST function. (2% chose this)
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How can reception of certain NAVTEX broadcasts be prevented?
  • The receiver can be programmed to reject certain stations and message categories. (92% chose this)
  • Stations are limited to daytime operation only. (2% chose this)
  • Coordinating reception with published broadcast schedules. (0% chose this)
  • Automatic receiver desensitization during night hours. (6% chose this)
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Which of the following best describes the "Capture effect?"
  • The receiver will accept all signals near the operating frequency. (13% chose this)
  • The receiver will reject all but the weakest signal. (2% chose this)
  • The receiver will reject all but the strongest signal. (81% chose this)
  • The receiver will modulate an adjacent transmitter. (5% chose this)
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There is no display on the monitor. What are the most likely causes?
  • Bad video card, defective RAM or bad CD-ROM. (7% chose this)
  • Bad video card, bad 15 pin video connector or no power to monitor. (91% chose this)
  • Defective CD-ROM Drive. (2% chose this)
  • Fragmented Hard Drive. (0% chose this)
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The printer will not print a document. Which of the following is NOT a likely reason?
  • The graphics card is defective. (85% chose this)
  • The printer queue is frozen. (5% chose this)
  • The printer may be out of toner or ink. (3% chose this)
  • There may be a paper jam in the printer. (7% chose this)
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