T3C
Ionospheric propagation, causes and variation; maximum usable
frequency;
Sporadic-E propagation; ground wave, HF propagation
characteristics;
sunspots and the sunspot cycle
T3C01
@T3B01
Which
region of the ionosphere is mainly responsible for absorbing
MF/HF
radio signals during the daytime?
A. The F2 region
B. The F1 region
C. The E region
D. The D region
T3C02
@T3B05
If you
are receiving a weak and distorted signal from a distant
station
on a frequency close to the maximum usable frequency, what
type of
propagation is probably occurring?
A. Ducting
B. Line-of-sight
C. Scatter
D. Ground-wave
T3C03
@T3B14
In
relation to sky-wave propagation, what does the term "maximum
usable
frequency" (MUF) mean?
A. The highest frequency signal that will reach
its intended
destination
B. The lowest frequency signal that will reach
its intended
destination
C. The highest frequency signal that is most
absorbed by the
ionosphere
D. The lowest frequency signal that is most
absorbed by the
ionosphere
T3C04
@N3A03
When a
signal travels along the surface of the Earth, what is this
called?
A. Sky-wave propagation
B. Knife-edge diffraction
C. E-region propagation
D. Ground-wave propagation
T3C05
@N3A05
When a
signal is returned to Earth by the ionosphere, what is this
called?
A. Sky-wave propagation
B. Earth-Moon-Earth propagation
C. Ground-wave propagation
D. Tropospheric propagation
T3C06
@N3A07
What is
a skip zone?
A. An area covered by ground-wave propagation
B. An area covered by sky-wave propagation
C. An area that is too far away for ground-wave
propagation, but too
close
for sky-wave propagation
D. An area that is too far away for ground-wave
or sky-wave
propagation
T3C07
@N3A12
Which
ionospheric region is closest to the Earth?
A. The A region
B. The D region
C. The E region
D. The F region
T3C08
@N3A13
Which
region of the ionosphere is mainly responsible for long-
distance
sky-wave radio communications?
A. D region
B. E region
C. F1 region
D. F2 region
T3C09
@N3A14
Which
of the ionospheric regions may split into two regions only
during
the daytime?
A. Troposphere
B. F
C. Electrostatic
D. D
T3C10
@N3A16
How
does the number of sunspots relate to the amount of ionization in
the
ionosphere?
A. The more sunspots there are, the greater the
ionization
B. The more sunspots there are, the less the
ionization
C. Unless there are sunspots, the ionization is
zero
D. Sunspots do not affect the ionosphere
T3C11
@N3A17
How
long is an average sunspot cycle?
A. 2 years
B. 5 years
C. 11 years
D. 17 years