Practice Test Geeks(VDV) Voice Data Video Technician Certified Practice Test
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Testing & Troubleshooting Flashcards

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

Read the first 7 Testing & Troubleshooting flashcards as text

  1. A technician measures -3.5 dB return loss on a coaxial cable connector. What does this indicate?

    Answer: Moderate signal reflection due to impedance mismatch

    A return loss of -3.5 dB indicates significant signal reflection back toward the source, which is caused by an impedance mismatch at the connector.

  2. When using a toner and probe kit to trace a cable, the probe produces no tone on any cable in a bundle. What is the most likely cause?

    Answer: The toner is not connected to the correct pair or is faulty

    If no tone is detected on any cable, the most likely cause is that the toner is not properly connected to the target cable or the toner unit itself is malfunctioning.

  3. A VoIP phone loses audio quality intermittently during calls. Which test tool best identifies the root cause?

    Answer: Network packet analyzer (protocol analyzer)

    A protocol analyzer (such as Wireshark) captures packets to reveal jitter, packet loss, and latency—the primary causes of intermittent VoIP audio degradation.

  4. A coaxial cable run tests with higher-than-expected attenuation. Which of the following is the LEAST likely cause?

    Answer: Low ambient temperature

    Low ambient temperature actually reduces attenuation slightly; excessive length, physical damage, and impedance mismatches are all common causes of elevated attenuation.

  5. During a CATV signal level sweep test, a technician notices a 6 dB drop at all frequencies above 550 MHz. What is the most probable cause?

    Answer: Water-damaged cable segment acting as a high-frequency low-pass filter

    Water ingress into coaxial cable or connectors creates a low-pass filter effect, causing greater attenuation at higher frequencies.

  6. A technician installs a structured cabling system and the cable certifier reports 'FAIL – Near-End Crosstalk (NEXT)'. Which action is MOST likely to resolve this?

    Answer: Re-terminate the connectors, ensuring minimum untwisting of pairs

    Excessive untwisting of twisted pairs during termination is the most common cause of NEXT failures; re-terminating with minimal untwist typically resolves this.

  7. An OTDR trace shows a spike (gainer) in the middle of a fiber run where no splice or connector exists. What does this indicate?

    Answer: A difference in backscatter coefficients between two fiber sections joined at that point

    A gainer artifact on an OTDR trace typically results from a splice between fibers with different backscatter coefficients, making the far section appear to have lower loss than it does.