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4-35. Which of the following radiation patterns
is/are exhibited by a simple vertical
doublet antenna?
1. Nondirectional in the horizontal plane
2. Directional in the vertical plane
3. Both 1 and 2 above
4. Spherical in all planes
4-36. A method of feeding energy to a half-
wave antenna is to connect one end
through a capacitor to the output stage.
What is this method of feeding called?
1. End feed
2. Voltage feed
3. Both 1 and 2 above
4. Current feed
4-37. An antenna supplied by the center-feed
method is fed at what point?
1. Low voltage and low current
2. Low voltage and high current
3. High voltage and low current
4. High voltage and high current
4-38. The basic Marconi antenna has which of
the following characteristics?
1. One-quarter wavelength and
ungrounded
2. One-half wavelength and grounded at
one end
3. One-half wavelength and insulated
from ground
4. One-quarter wavelength and
grounded at one end
4-39. The Marconi antenna behaves as a dipole
for which of the following reasons?
1. It is fed at one end
2. An image antenna is formed by
reflections from the ground
3. A quarter-wavelength of conductor is
buried in the ground and forms the
rest of the dipole
4. The applied signal is rectified so that
only half the signal will appear on the
quarter-wave antenna
4-40. A series of conductors arranged in a
radial pattern and buried in the ground
beneath the antenna is referred to as a
1. ground spur
2. counterpoise
3. ground screen
4. ground reflector
4-41. A folded dipole can be used instead of a
simple, center-fed dipole for which of the
following purposes?
1. Matching voltage
2. Matching impedance
3. Increasing directivity
4. Decreasing directivity
4-42. An antenna arrangement that has
elements aligned in a straight line is
referred to as what type array?
1. Isotropic
2. Collinear
3. Line-of-sight
4. Unidirectional
4-43. To have current in two adjoining
collinear half-wave elements in proper
phase, they must be connected by which
of the following stubs?
1. A shorted half-wave stub
2. An open quarter-wave stub
3. A shorted eighth-wave stub
4. A shorted quarter-wave stub
4-44. To select a desired signal and
discriminate against interfering signals,
the receiving antenna should have which
of the following characteristics?
1. Be omnidirectional
2. Be highly directional
3. Be vertically polarized
4. Be horizontally polarized
