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2-58. When ducting is present in the
atmosphere, multihop refraction of
line-of-sight transmission can occur
because of which of the following factors?
1. Operating frequency of the transmitter
2. Height of the transmitting antenna
3. Angle of incidence of the radio wave
4. Each of the above
2-59. A propagation technique used to extend
uhf transmission range beyond the horizon
uses which of the following propagation
characteristics?
1. Ground reflection
2. Ionospheric scatter
3. Tropospheric scatter
4. Atmospheric refraction
2-60. Communications by tropospheric scatter
can be affected by which of the following
conditions?
1. Sunspot activity
2. Atmospheric conditions
3. Ionospheric disturbances
4. All of the above
2-61. What effect, if any, does the radiation
angle of a transmitting antenna have on
the reception of communications by
tropospheric scatter?
1. The lower the angle, the weaker the
signal
2. The lower the angle, the stronger the
signal
3. The lower the angle, the more
susceptible the signal is to distortion
4. None
2-62. Which of the following descriptions of
tropospheric scatter signal reception is
NOT true?
1. Receiver signal strength decreases as
the turbulence height is increased
2. The level of reception depends on the
number of turbulences causing scatter
3. The energy received is the portion of
the wave reradiated by the turbulence
4. Increased communications distance
enables more turbulence to act on the
signal, thereby raising the received
signal level
2-63. The tropospheric scatter signal is often
characterized by very rapid fading caused
by which of the following factors?
1. Extreme path lengths
2. Multipath propagation
3. Turbulence in the atmosphere
4. Angle of the transmitted beam
2-64. For which of the following
communications situations would
turbulence in the troposphere scatter
transmission?
1. 10 MHz, range 200 miles
2. 30 MHz, range 800 miles
3. 50 MHz, range 600 miles
4. 100 MHz, range 400 miles
