E3B Transequatorial; long path; gray
line
E3B01
(A)
What is
transequatorial propagation?
A. Propagation between two
points at approximately the same distance north and south of the magnetic
equator
B. Propagation between two points at
approximately the same latitude on the magnetic equator
C. Propagation between two continents by way of
ducts along the magnetic equator
D. Propagation between two stations at the same
latitude
E3B02
(C)
What is
the approximate maximum range for signals using transequatorial propagation?
A. 1000 miles
B. 2500 miles
C. 5000 miles
D. 7500 miles
E3B03
(C)
What is
the best time of day for transequatorial propagation?
A. Morning
B. Noon
C. Afternoon or early
evening
D. Late at night
E3B04
(A)
What
type of propagation is probably occurring if a beam antenna must be pointed in
a direction 180 degrees away from a station to receive the strongest signals?
A. Long-path
B. Sporadic-E
C. Transequatorial
D. Auroral
E3B05
(D)
On what
amateur bands can long-path propagation provide signal enhancement?
A. 160 to 40 meters
B. 30 to 10 meters
C. 160 to 10 meters
D. 160 to 6 meters
E3B06
(B)
What
amateur band consistently yields long-path enhancement using a modest antenna
of relatively high gain?
A. 80 meters
B. 20 meters
C. 10 meters
D. 6 meters
E3B07
(D)
What is
the typical reason for hearing an echo on the received signal of a station in
Europe while directing your HF antenna toward the station?
A. The station's transmitter has poor frequency
stability
B. The station's transmitter is producing
spurious emissions
C. Auroral conditions are causing a direct and
a long-path reflected signal to be received
D. There are two signals
being received, one from the most direct path and one from long-path propagation
E3B08
(D)
What
type of propagation is probably occurring if radio signals travel along the
earth's terminator?
A. Transequatorial
B. Sporadic-E
C. Long-path
D. Gray-line
E3B09
(A)
At what
time of day is gray-line propagation most prevalent?
A. Twilight, at sunrise and
sunset
B. When the sun is directly above the location
of the transmitting station
C. When the sun is directly overhead at the
middle of the communications path between the two stations
D. When the sun is directly above the location
of the receiving station
E3B10
(B)
What is
the cause of gray-line propagation?
A. At midday the sun, being directly overhead,
superheats the ionosphere causing increased refraction of radio waves
B. At twilight solar
absorption drops greatly while atmospheric ionization is not weakened enough to
reduce the MUF
C. At darkness solar absorption drops greatly
while atmospheric ionization remains steady
D. At midafternoon the sun heats the
ionosphere, increasing radio wave refraction and the MUF
E3B11
(C)
What
communications are possible during gray-line propagation?
A. Contacts up to 2,000 miles only on the
10-meter band
B. Contacts up to 750 miles on the 6- and
2-meter bands
C. Contacts up to 8,000 to
10,000 miles on three or four HF bands
D. Contacts up to 12,000 to 15,000 miles on the
10- and 15-meter bands
E3C Auroral propagation; selective
fading; radio-path horizon; take-
off
angle over flat or sloping terrain; earth effects on propagation
E3C01
(D)
What
effect does auroral activity have upon radio communications?
A. The readability of SSB signals increases
B. FM communications are clearer
C. CW signals have a clearer tone
D. CW signals have a
fluttery tone
E3C02
(C)
What is
the cause of auroral activity?
A. A high sunspot level
B. A low sunspot level
C. The emission of charged
particles from the sun
D. Meteor showers concentrated in the northern
latitudes
E3C03
(D)
Where
in the ionosphere does auroral activity occur?
A. At F-region height
B. In the equatorial band
C. At D-region height
D. At E-region height
E3C04
(A)
Which
emission modes are best for auroral propagation?
A. CW and SSB
B. SSB and FM
C. FM and CW
D. RTTY and AM
E3C05
(B)
What
causes selective fading?
A. Small changes in beam heading at the receiving
station
B. Phase differences between
radio-wave components of the same transmission, as experienced at the receiving
station
C. Large changes in the height of the
ionosphere at the receiving station ordinarily occurring shortly after either
sunrise or sunset
D. Time differences between the receiving and
transmitting stations
E3C06
(B)
Which
emission modes suffer the most from selective fading?
A. CW and SSB
B. FM and double sideband AM
C. SSB and AMTOR
D. SSTV and CW
E3C07
(A)
How
does the bandwidth of a transmitted signal affect selective fading?
A. It is more pronounced at
wide bandwidths
B. It is more pronounced at narrow bandwidths
C. It is the same for both narrow and wide
bandwidths
D. The receiver bandwidth determines the selective
fading effect
E3C08
(A)
How
much farther does the VHF/UHF radio-path horizon distance exceed the geometric
horizon?
A. By approximately 15% of
the distance
B. By approximately twice the distance
C. By approximately one-half the distance
D. By approximately four times the distance
E3C09
(B)
For a
3-element Yagi antenna with horizontally mounted elements, how does the main
lobe takeoff angle vary with height above flat ground?
A. It increases with increasing height
B. It decreases with
increasing height
C. It does not vary with height
D. It depends on E-region height, not antenna
height
E3C10
(B)
What is
the name of the high-angle wave in HF propagation that travels for some
distance within the F2 region?
A. Oblique-angle ray
B. Pedersen ray
C. Ordinary ray
D. Heaviside ray
E3C11
(C)
What
effect is usually responsible for propagating a VHF signal over 500 miles?
A. D-region absorption
B. Faraday rotation
C. Tropospheric ducting
D. Moonbounce
E3C12
(A)
What
happens to an electromagnetic wave as it encounters air molecules and other
particles?
A. The wave loses kinetic
energy
B. The wave gains kinetic energy
C. An aurora is created
D. Nothing happens because the waves have no
physical substance