Practice Test Geeks(CMRT) Certified Marine Radar Technician Practice Test
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Installation & Maintenance Procedures Flashcards

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

Read the first 7 Installation & Maintenance Procedures flashcards as text

  1. When installing a marine radar antenna on a mast, what is the minimum safe clearance recommended between the radar beam and the highest point where crew members may stand?

    Answer: 3 meters

    A minimum 3-meter clearance between the rotating radar beam and any occupied crew area is standard safety practice to limit RF exposure.

  2. During radar installation, coaxial cable runs should be secured at intervals no greater than:

    Answer: 120 cm (48 inches)

    Coaxial cables should be supported at maximum 120 cm intervals to prevent excessive bending stress and signal degradation from cable movement.

  3. What is the primary reason for installing ferrite chokes on radar power supply leads near the transceiver unit?

    Answer: Suppress conducted RF interference

    Ferrite chokes suppress high-frequency conducted emissions that can travel along power leads and interfere with other electronic equipment.

  4. When aligning a radar scanner after installation, heading marker alignment is verified by:

    Answer: Comparing the radar heading line to a known fixed bearing

    The heading marker is aligned by rotating the antenna until the radar heading line corresponds precisely with a charted fixed object at a known bearing.

  5. Radar waveguide sections on a vessel should be pressure-tested with dry nitrogen or dry air to check for:

    Answer: Moisture ingress and pressure integrity

    Pressurizing waveguide with dry gas reveals leaks and verifies the system will resist moisture infiltration that degrades RF transmission.

  6. When replacing a radar display unit onboard, the technician should first:

    Answer: Isolate and lock out the radar power supply

    Lockout/tagout of the radar power supply is mandatory before replacing any below-decks unit to prevent electric shock from high-voltage circuits.

  7. What maintenance check should be performed on the radar antenna pedestal bearing at each scheduled service interval?

    Answer: Inspect and lubricate bearings per manufacturer specification

    Pedestal bearings must be inspected for wear and lubricated per manufacturer intervals to ensure smooth antenna rotation and accurate scan.