Z3D153 - 2016 Edit Code 3, Volume 2 Part 2

21 Questions | Total Attempts: 116

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Z3D153 Quizzes & Trivia

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Questions and Answers
  • 1. 
    The Earth’s conductivity is determined by the type of
    • A. 

      Atmospheric conditions at the time of transmission.

    • B. 

      Air and moisture content in the propagation path.

    • C. 

      Soil and water in the propagation path.

    • D. 

      Soil and air in the propagation path.

  • 2. 
    This term is used to describe radio waves that bend as they travel from one medium toanother that has different density.
    • A. 

      Diffusion.

    • B. 

      Diffraction.

    • C. 

      Refraction.

    • D. 

      Reflection.

  • 3. 
    The refractive index of air depends on moisture,
    • A. 

      Atmospheric pressure, and temperature.

    • B. 

      Atmospheric pressure, and frequency.

    • C. 

      Receive signal level, and temperature.

    • D. 

      Receive signal level, and frequency.

  • 4. 
    When comparing the radio and optical horizons, which one is farther away and by what percentage?
    • A. 

      Optical; 15.

    • B. 

      Radio; 15.

    • C. 

      Optical; 33.

    • D. 

      Radio; 33.

  • 5. 
    Which process permits communication in shadow regions behind obstacles?
    • A. 

      Reflection.

    • B. 

      Scattering.

    • C. 

      Refraction.

    • D. 

      Diffraction.

  • 6. 
    Which frequency range will show little effect from precipitation?
    • A. 

      High frequency (HF).

    • B. 

      Ultra-high frequency (UHF).

    • C. 

      Super-high frequency (SHF).

    • D. 

      Extremely-high frequency (EHF).

  • 7. 
    Line-of-sight (LOS) radio waves that are guided through the air between two layers of the atmosphere are known as
    • A. 

      Channeling.

    • B. 

      Guiding.

    • C. 

      Ducting.

    • D. 

      Piping.

  • 8. 
    Which condition gives sky-wave propagation its ability to communicate beyond the optical line-of-sight (LOS)?
    • A. 

      Refraction.

    • B. 

      Reflection.

    • C. 

      Earth’s conductivity.

    • D. 

      Atmospheric charge.

  • 9. 
    The angle at which a radio wave enters the ionosphere is known as the
    • A. 

      Skip angle.

    • B. 

      Critical angle.

    • C. 

      Angle of entrance.

    • D. 

      Angle of incidence.

  • 10. 
    There are several critical sky-wave propagation angles and frequencies. Radio waves that angle too low are
    • A. 

      Refracted.

    • B. 

      Returned to Earth.

    • C. 

      Absorbed before refraction occurs.

    • D. 

      Passed through the ionosphere into space.

  • 11. 
    In sky-wave propagation, frequencies higher than the critical frequency are
    • A. 

      Returned to Earth.

    • B. 

      Passed into space.

    • C. 

      The most desirable.

    • D. 

      Refracted by the F2 layer.

  • 12. 
    The term frequency of optimum transmission (FOT) is also referred to as the
    • A. 

      Outbound traffic frequency.

    • B. 

      Optimum tropospheric frequency.

    • C. 

      Optimum traffic frequency.

    • D. 

      Frequency of outbound transmission.

  • 13. 
    In sky- and ground-wave propagation, the area of silence where no signals are received is known as the
    • A. 

      Propagation distance.

    • B. 

      Skip distance.

    • C. 

      Dead zone.

    • D. 

      Skip zone.

  • 14. 
    This occurs when a transmitted signal travels over two or more separate paths during transmission.
    • A. 

      Skip effects.

    • B. 

      Modulation.

    • C. 

      Multipathing.

    • D. 

      Magneton splitting.

  • 15. 
    How many layers make up the Earth’s atmosphere?
    • A. 

      2.

    • B. 

      3.

    • C. 

      4.

    • D. 

      5.

  • 16. 
    This occurs when high-energy ultraviolet light waves from the sun enter the ionospheric region of the atmosphere and strike the gas atoms.
    • A. 

      Ionization.

    • B. 

      Modulation.

    • C. 

      Conductivity.

    • D. 

      Recombination.

  • 17. 
    The atmospheric recombination process is dependent on the
    • A. 

      Season.

    • B. 

      Time of day (TOD).

    • C. 

      Regular variation.

    • D. 

      Irregular variations.

  • 18. 
    Which layer of the ionosphere is most important for high-frequency (HF) communications?
    • A. 

      D.

    • B. 

      E.

    • C. 

      F.

    • D. 

      Topside.

  • 19. 
    During which season do we have the wider range of critical frequencies and less absorption of all frequencies?
    • A. 

      Fall.

    • B. 

      Winter.

    • C. 

      Spring.

    • D. 

      Summer.

  • 20. 
    As ionospheric solar variations, sunspots are disturbances that appear and disappear
    • A. 

      In the sun’s atmosphere.

    • B. 

      On the sun’s surface.

    • C. 

      In the ionosphere

    • D. 

      Beneath the sun’s surface.

  • 21. 
    On which regular ionospheric variation do sunspots occur?
    • A. 

      11-day cycle.

    • B. 

      11-week cycle.

    • C. 

      11-month cycle.

    • D. 

      11-year cycle.