All 30 FCC GROL questions for 3N Marine with the correct answers marked, from the official current FCC question pool. Test yourself with the free practice exam.
3-85N1
What is the channel spacing used for VHF marine radio?
A. 10 kHz.
B. 12.5 kHz.
C. 20 kHz.
D. 25 kHz. ✓
3-85N2
What VHF channel is assigned for distress and calling?
A. 70
B. 16 ✓
C. 21A
D. 68
3-85N3
What VHF Channel is used for Digital Selective Calling and acknowledgement?
A. 16
B. 21A
C. 70 ✓
D. 68
3-85N4
Maximum allowable frequency deviation for VHF marine radios is:
A. +/- 5 kHz. ✓
B. +/- 15 kHz.
C. +/- 2.5 kHz.
D. +/- 25 kHz.
3-85N5
What is the reason for the USA-INT control or function?
A. It changes channels that are normally simplex channels into duplex channels.
B. It changes some channels that are normally duplex channels into simplex channels. ✓
C. When the control is set to “INT” the range is increased.
D. None of the above.
3-85N6
How might an installer verify correct GPS sentence to marine DSC VHF radio?
A. Look for latitude and longitude, plus speed, on VHF display. ✓
B. Press and hold the red distress button.
C. Look for GPS confirmation readout.
D. Ask for VHF radio check position report.
3-86N1
What is a common occurrence when voice-testing an SSB aboard a boat?
A. Ammeter fluctuates down with each spoken word.
B. Voltage panel indicator lamps may glow with each syllable. ✓
C. Automatic tuner cycles on each syllable.
D. Minimal voltage drop seen at power source.
3-86N2
What might contribute to apparent low voltage on marine SSB transmitting?
A. Blown red fuse.
B. Too much grounding.
C. Blown black negative fuse. ✓
D. Antenna mismatch.
3-86N3
What type of wire connects an SSB automatic tuner to an insulated backstay?
A. RG8U.
B. RG213.
C. 16-gauge two-conductor.
D. GTO-15 high-voltage cable. ✓
3-86N4
Which of the following statements concerning SITOR communications is true?
A. ARQ message transmissions are made in data groups consisting of three-character blocks. ✓
B. ARQ transmissions are acknowledged by the Information Receiving Station only at the end of the message.
C. ARQ communications rely upon error correction by time diversity transmission and reception.
D. Forward error correction is an interactive mode.
3-86N5
The sequence ARQ, FEC, SFEC best corresponds to which of the following sequences?
A. One-way communications to a single station, one-way communications to all stations, two-way communications.
B. One-way communications to all stations, two-way communications, one-way communications to a single station.
C. Two way communications, one-way communications to all stations, one-way communications to a single station. ✓
D. Two way communications, one-way communications to a single station, one-way communications to all stations.
3-86N6
Which of the following statements concerning SITOR communications is true?
A. Communication is established on the working channel and answerbacks are exchanged before FEC broadcasts can be received.
B. In the ARQ mode each character is transmitted twice.
C. Weather broadcasts cannot be made in FEC because sending each character twice would cause the broadcast to be prohibitively long.
D. Two-way communication with the coast radio station using FEC is not necessary to be able to receive the broadcasts. ✓
3-87N1
What causes the SART to begin a transmission?
A. When activated manually, it begins radiating immediately.
B. After being activated the SART responds to RADAR interrogation. ✓
C. It is either manually or water activated before radiating.
D. It begins radiating only when keyed by the operator.
3-87N2
How should the signal from a Search And Rescue RADAR Transponder appear on a RADAR display?
A. A series of dashes.
B. A series of spirals all originating from the range and bearing of the SART.
C. A series of twenty dashes.
D. A series of 12 equally spaced dots. ✓
3-87N3
In which frequency band does a search and rescue transponder operate?
A. 9 GHz ✓
B. 3 GHz
C. S-band
D. 406 MHz
3-87N4
Which piece of required GMDSS equipment is the primary source of transmitting locating signals?
A. Radio Direction Finder (RDF).
B. A SART transmitting on 406 MHz.
C. Survival Craft Transceiver.
D. An EPIRB transmitting on 406 MHz. ✓
3-87N5
Which of the following statements concerning satellite EPIRBs is true?
A. Once activated, these EPIRBs transmit a signal for use in identifying the vessel and for determining the position of the beacon. ✓
B. The coded signal identifies the nature of the distress situation.
C. The coded signal only identifies the vessel’s name and port of registry.
D. If the GMDSS Radio Operator does not program the EPIRB, it will transmit default information such as the follow-on communications frequency and mode.
3-87N6
What statement is true regarding 406 MHz EPIRB transmissions?
A. Allows immediate voice communications with the RCC.
B. Coding permits the SAR authorities to know if manually or automatically activated.
C. Transmits a unique hexadecimal identification number. ✓
D. Radio Operator programs an I.D. into the SART immediately prior to activation.
3-88N1
What is facsimile?
A. The transmission of still pictures by slow-scan television.
B. The transmission of characters by radioteletype that form a picture when printed.
C. The transmission of printed pictures for permanent display on paper. ✓
D. The transmission of video by television.
3-88N2
What is the standard scan rate for high-frequency 3 MHz - 23 MHz weather facsimile reception from shore stations?
A. 240 lines per minute.
B. 120 lines per minute. ✓
C. 150 lines per second.
D. 60 lines per second.
3-88N3
What would be the bandwidth of a good crystal lattice band-pass filter for weather facsimile HF (high frequency) reception?
A. 500 Hz at -6 dB.
B. 6 kHz at -6 dB.
C. 1 kHz at -6 dB. ✓
D. 15 kHz at -6 dB.
3-88N4
Which of the following statements about NAVTEX is true?
A. Receives MSI broadcasts using SITOR-B or FEC mode. ✓
B. The ship station transmits on 518 kHz.
C. The ship receives MSI broadcasts using SITOR-A or ARQ mode.
D. NAVTEX is received on 2182 kHz using SSB.
3-88N5
Which of the following is the primary frequency that is used exclusively for NAVTEX broadcasts internationally?
A. 2187.5 kHz.
B. 4209.5 kHz.
C. VHF channel 16.
D. 518 kHz. ✓
3-88N6
What determines whether a NAVTEX receiver does not print a particular type of message content?
A. The message does not concern your vessel.
B. The subject indicator matches that programmed for rejection by the operator. ✓
C. The transmitting station ID covering your area has not been programmed for rejection by the operator.
D. All messages sent during each broadcast are printed.
3-89N1
What data language is bi-directional, multi-transmitter, multi-receiver network?
A. NMEA 2000. ✓
B. NMEA 0181.
C. NMEA 0182.
D. NMEA 0183.
3-89N2
How should shielding be grounded on an NMEA 0183 data line?
A. Unterminated at both ends.
B. Terminated to ground at the talker and unterminated at the listener. ✓
C. Unterminated at the talker and terminated at the listener.
D. Terminated at both the talker and listener.
3-89N3
What might occur in NMEA 2000 network topology if one device in line should fail?
A. The system shuts down until the device is removed.
B. Other electronics after the failed device will be inoperable.
C. The main fuse on the backbone may open.
D. There will be no interruption to all other devices. ✓
3-89N4
In an NMEA 2000 device, a load equivalence number (LEN) of 1 is equivalent to how much current consumption?
A. 50 mA ✓
B. 10 mA
C. 25 mA
D. 5 mA
3-89N5
An NMEA 2000 system with devices in a single location may be powered using this method:
A. Dual mid-powered network.
B. End-powered network. ✓
C. Individual devices individually powered.
D. No 12 volts needed for NMEA 2000 devices.
3-89N6
What voltage drop at the end of the last segment will satisfy NMEA 2000 network cabling plans?
A. 0.5 volts
B. 2.0 volts
C. 1.5 volts ✓
D. 3.0 volts