NZART Amateur Examination                     page 9          NZARTX07 Security code 267036

  1. The resonant frequency of an antenna may be increased by:
    1. shortening the radiating element
    2. lengthening the radiating element
    3. increasing the height of the radiating element
    4. lowering the radiating element

  2. A Yagi antenna is said to have a power gain over a dipole antenna for the same frequency band because:
    1. it radiates more power than a dipole
    2. more powerful transmitters can use it
    3. it concentrates the radiation in one direction
    4. it can be used for more than one band

  3. The medium which reflects high frequency radio waves back to the earth's surface is called the:
    1. biosphere
    2. stratosphere
    3. ionosphere
    4. troposphere

  4. Signal fadeouts resulting from an 'ionospheric storm' or 'sudden ionospheric disturbance' are usually attributed to:
    1. heating of the ionised layers
    2. over-use of the signal path
    3. insufficient transmitted power
    4. solar flare activity

  5. The skip distance of radio signals is determined by the:
    1. type of transmitting antenna used
    2. power fed to the final amplifier of the transmitter
    3. only the angle of radiation from the antenna
    4. both the height of the ionosphere and the angle of radiation from the antenna

  6. If the frequency of a transmitted signal is so high that we no longer receive a reflection from the ionosphere, the signal frequency is above the:
    1. speed of light
    2. sun spot frequency
    3. skip distance
    4. maximum usable frequency

  7. The usual effect of ionospheric storms is to:
    1. increase the maximum usable frequency
    2. cause a fade-out of sky-wave signals
    3. produce extreme weather changes
    4. prevent communications by ground wave
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