Practice Test Geeks(CPCT) Certified Premises Cabling Technician Practice Test
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Cable Testing & Troubleshooting Flashcards

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

Read the first 7 Cable Testing & Troubleshooting flashcards as text

  1. A technician uses a tone generator and probe to trace a cable. In a busy equipment room with many cables, the probe gives a faint signal on the target cable but also picks up tone on adjacent cables. What is the most likely cause?

    Answer: Capacitive coupling between tightly bundled cables

    Capacitive coupling between adjacent cables in a bundle allows the tone signal to bleed onto neighboring conductors, producing false signals on untargeted cables.

  2. When certifying a fiber optic link, an OTDR trace shows a 'gainer' — a point where the backscatter level appears to increase. What does this indicate?

    Answer: A fiber section with lower backscatter coefficient preceding a higher-backscatter section

    A gainer occurs when transitioning from a fiber with lower backscatter to one with higher backscatter, making the splice appear as a gain rather than a loss.

  3. Which test parameter specifically measures the signal strength at the far end of a cable pair after traveling the full link length?

    Answer: Insertion Loss (Attenuation)

    Insertion loss (also called attenuation) measures the reduction in signal amplitude from one end of the cable to the other.

  4. A newly installed Cat 6 horizontal run fails the ANEXT test. Which factor unique to alien crosstalk testing should the technician investigate first?

    Answer: The proximity and bundling of adjacent cables in the pathway

    Alien NEXT (ANEXT) is caused by crosstalk from cables outside the link under test; tightly bundled or parallel cables in the same conduit are the primary source.

  5. When performing a two-fiber OTDR test on a duplex multimode link, the technician notices that one fiber shows much higher loss than the other. The cables were installed in the same conduit. What should be checked first?

    Answer: Inspect and clean the connector on the high-loss fiber

    A dirty or damaged connector face is the most common cause of excessive loss on a single fiber when adjacent fibers in the same installation are fine.

  6. A link passes the insertion loss test but fails ELFEXT. What does this failure indicate?

    Answer: Crosstalk energy is coupling from one pair to another and exiting at the far end

    ELFEXT (Equal Level Far-End Crosstalk) measures the far-end crosstalk normalized to the insertion loss, indicating crosstalk interference arriving at the far end of the disturbed pair.

  7. A technician certifies a Cat 6 channel and notices the wiremap shows pairs 1-2 and 3-6 are correct, but pairs 4-5 and 7-8 are swapped end-to-end. What type of fault is this?

    Answer: Transposed pairs

    A transposed pair fault occurs when entire pairs are swapped between their correct positions at both ends, distinguished from a split pair which intermixes conductors from different pairs.