Practice Test Geeks(VDV) Voice Data Video Technician Certified Practice Test
← All VDV Flashcard Decks

Fiber Optics 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 Fiber Optics flashcards as text

  1. What does an 'APC' fiber connector end-face polish provide compared to a 'UPC' polish?

    Answer: Higher return loss due to its angled 8-degree end-face

    APC (Angled Physical Contact) connectors have an 8-degree angled end-face that reflects light away from the core, achieving return loss >60 dB versus ~55 dB for UPC.

  2. Which parameter measured in dB represents the total allowed signal loss for a fiber optic link from source to receiver?

    Answer: Optical power budget (loss budget)

    The optical power (loss) budget is the difference between transmitter output power and receiver sensitivity, defining the maximum allowable link loss.

  3. What causes 'Rayleigh scattering' loss in optical fiber?

    Answer: Microscopic density variations in the glass material

    Rayleigh scattering occurs when light interacts with tiny density fluctuations inherent in the glass structure, and is the dominant loss mechanism at shorter wavelengths.

  4. A VDV technician must install fiber in a plenum space. Which cable type must be used?

    Answer: OFNP (Plenum rated) fiber

    OFNP (Optical Fiber Nonconductive Plenum) cables are required in plenum spaces because they have low-smoke, flame-retardant jackets that meet NEC Article 770 requirements.

  5. What is the typical core/cladding diameter of standard 62.5 µm multimode fiber?

    Answer: 62.5/125 µm

    Standard 62.5 µm multimode fiber has a 62.5 µm core and 125 µm cladding diameter, making it compatible with LED-based transmitters.

  6. Which test instrument measures the optical power output of a fiber optic transmitter or the power at the end of a fiber link?

    Answer: Optical power meter

    An optical power meter directly measures light power in dBm or watts and is used with a light source to perform insertion loss tests on fiber links.

  7. What is the main advantage of using a visual fault locator (VFL) during fiber installation?

    Answer: It visually identifies breaks, bends, and bad splices by showing red light leaking from the fiber

    A VFL injects visible red laser light (typically 650 nm) into the fiber; breaks or severe bends glow red, making faults easy to locate visually.