Practice Test Geeks(CST) Certified Surveillance Technician Practice Test
← All CST Flashcard Decks

Maintenance and Troubleshooting Flashcards

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

Read the first 7 Maintenance and Troubleshooting flashcards as text

  1. A camera shows a strong horizontal rolling bar across the image. This artifact is most commonly caused by:

    Answer: Ground loop interference

    Ground loops create a potential difference between equipment grounds, inducing 60 Hz hum that appears as a rolling horizontal bar on analog video.

  2. When troubleshooting an IP camera that intermittently drops from the network, what is the correct first diagnostic step?

    Answer: Check PoE switch port utilization and power budget

    Intermittent dropouts on PoE cameras often result from insufficient power budget or switch port overload, which should be verified before other steps.

  3. A technician is cleaning camera domes on a quarterly maintenance visit. Which cleaning agent should be avoided?

    Answer: Ammonia-based glass cleaner

    Ammonia-based cleaners can cloud polycarbonate dome covers over time, permanently degrading optical clarity.

  4. An NVR shows 'HDD Not Detected' after a fan failure event. What is the most likely explanation?

    Answer: Overheating from the failed fan caused the HDD to shut down or fail

    Fan failure leads to thermal overload, which can cause hard drives to power down or suffer permanent damage from excessive heat.

  5. What does a 'video loss' alarm on a DVR typically indicate in an analog camera system?

    Answer: The camera has lost power or the coax connection is broken

    A video loss alarm triggers when the DVR detects no sync signal on an input, most commonly due to camera power loss or a severed coaxial cable.

  6. Which of the following best describes the purpose of a surge protector on outdoor camera installations?

    Answer: To protect equipment from voltage spikes caused by lightning or power surges

    Surge protectors clamp transient voltage spikes, preventing damage to camera electronics from lightning strikes or power line surges.

  7. A camera's image is sharp in the center but blurry toward the edges. This defect is called:

    Answer: Field curvature or vignetting

    Field curvature causes the focal plane to be curved rather than flat, resulting in sharp center focus but blurred edges on a flat sensor.