Practice Test Geeks(GROL) General Radiotelephone Operator License Practice Test
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Marine Electronics and Radar Systems Flashcards

7 cards from real GROL practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Marine Electronics and Radar Systems flashcards as text

  1. What is the purpose of a Global Maritime Distress and Safety System (GMDSS) installation on a vessel?

    Answer: To ensure reliable distress alerting and communication on a global basis

    GMDSS provides a comprehensive set of radio communications procedures and equipment to ensure that ships in distress can quickly alert rescue authorities and other ships anywhere in the world.

  2. Which device in GMDSS automatically transmits a distress signal when submerged in water?

    Answer: EPIRB (Emergency Position-Indicating Radio Beacon)

    An EPIRB activates automatically when it detects immersion in water, transmitting a distress signal on 406 MHz (and a homing signal on 121.5 MHz) to the COSPAS-SARSAT satellite system.

  3. What frequency does a SART (Search and Rescue Transponder) respond on when interrogated by a ship's radar?

    Answer: 9 GHz (X-band radar)

    A SART responds to 9 GHz X-band radar interrogations and produces a distinctive pattern of 12 dots extending 8 nautical miles on the rescuing ship's radar display.

  4. What information is contained in a DSC (Digital Selective Calling) distress alert?

    Answer: Ship's MMSI, nature of distress, position, and time

    A DSC distress alert automatically includes the ship's Maritime Mobile Service Identity (MMSI), the nature of distress, GPS position, and UTC time of the alert.

  5. On which VHF channel must all vessels keep a continuous watch under GMDSS requirements?

    Answer: Channel 16

    VHF Channel 16 (156.8 MHz) is the international distress, safety, and calling channel on which all vessels equipped with VHF radiotelephone must maintain a continuous watch.

  6. What is the NAVTEX system primarily used for?

    Answer: Automatic reception of maritime safety information broadcasts

    NAVTEX is an automated system that broadcasts maritime safety information (navigational warnings, meteorological warnings, and SAR notices) on 518 kHz for automatic printing on a dedicated receiver.

  7. What is the maximum Equivalent Isotropically Radiated Power (EIRP) for an EPIRB operating on 406 MHz?

    Answer: 5 W

    EPIRBs operating on 406 MHz are required to transmit at approximately 5 W EIRP to ensure reliable detection by the COSPAS-SARSAT satellite system.