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1988-05-10
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FCC Technician Exam Question Pool. Subelement 3AI.
Antennas and Feed Lines. 3 Questions.
--------------------------------------------------
3I 1.1 D
What antenna type best strengthens signals from a particular
direction while attenuating those from other directions?
A. A Monopole antenna.
B. An Isotropic antenna.
C. A Vertical antenna.
D. A Beam antenna.
3I 1.2 C
What is a YAGI Antenna?
A. Half Wavelength elements stacked vertically
and excited in phase.
B. Quarter Wavelength elements arranged horizontally
and excited out of phase.
C. Half Wavelength linear driven element(s) with
parasitically excited parallel linear elements.
D. Quarter Wavelength, triangular loop elements.
3I 1.4 A
What is the general configuration of the radiating
elements of a horizontally polarized Yagi?
A. Two or more straight, parallel elements arranged
in the same horizontal plane.
B. Vertically stacked square or circular loops
arranged in parallel horizontal planes.
C. Two or more wire loops arranged
in parallel vertical planes.
D. A vertical radiator arranged in the center
of an effective RF ground plane.
3I 1.5 D
What type of Parasitic Beam Antenna uses
two or more straight metal tubing elements
arranged physically parallel to each other?
A. A Quad Antenna.
B. A Delta Loop Antenna.
C. A Zepp Antenna.
D. A Yagi Antenna.
3I 1.6 B
How many directly driven elements does a Yagi Antenna have?
A. None; they are all parasitic.
B. One.
C. Two.
D. All elements are directly driven.
3I 1.8 A
What is PARASITIC BEAM ANTENNA?
A. An antenna where the director and reflector
elements receive their RF excitation by induction
or radiation from the driven elements.
B. An antenna where wave traps are used to
assure mawnetic coupling among the elements.
C. An antenna where all elements are driven
by direct connection to the feed line.
D. An antenna where the driven element
receives its RF excitation by induction
or radiation from the driven elements.
3I 2.2 B
What kind of antenna array is composed of a Square Full Wave
Closed Loop Driven Element with Parallel Parasitic Element(s)?
A. Dual Rhombic.
B. Cubical Quad.
C. Stacked Yagi.
D. Delta Loop.
3I 2.3 D
Approximately how long is one side of the
driven element of a Cubical Quad Antenna?
A. 2 electrical wavelengths.
B. 1 electrical wavelength.
C. 1/2 electrical wavelength.
D. 1/4 electrical wavelength.
3I 2.4 C
Approximately how long is the wire in the
driven element of a Cubical Quad Antenna?
A. 1/4 electrical wavelength.
B. 1/2 electrical wavelength.
C. 1 electrical wavelength.
D. 2 electrical wavelengths.
3I 2.5 A
What is a DELTA LOOP ANTENNA?
A. A variation of the Quad Antenna with triangular elements.
B. A large copper ring used direction finding.
C. An antenna system composed of three Vertical
Antennas arranged in a triangular shape.
D. An antenna made from several
coils of wire on an insulating form.
3I 2.6 B
What is a QUBICAL QUAD ANTENNA?
A. Four parallel metal tubes, each
approximately 1/2 electrical wavelength long.
B. Two or more parallel four sided wire loops, each
approximately one electrical wavelength long.
C. A vertical conductor 1/4 electrical wavelength
high, fed at the bottom.
D. A center fed wire 1/2 electrical wavelength long.
3I 4.1 D
What is the polarization of electromagnetic
waves radiated from a Half Wavelength Antenna
mounted perpendicular to the Earth's surface?
A. Circularly polarized waves.
B. Horizontally polarized waves.
C. Parabolically polarized waves.
D. Vertically polarized waves.
3I 4.2 B
What is the electromagnetic wave polarization
of most Man Made Noise in the HF/VHF spectrum?
A. Left Hand Circular.
B. Vertically.
C. Right Hand Circular.
D. Horizontally.
3I 4.3 C
To what does the term VERTICAL
as applied to Wave Polarization refer?
A. This means that the electric lines of force
in the radio wave are parallel to the Earth's surface.
B. This means that the magnetic lines of force
in the radio wave are perpendicular to the Earth's surface.
C. This means that the electric lines of force
in the radio wave are perpendicular to the Earth's surface.
D. This means that the radio wave will leave
the antenna and radiate Vertically into the Ionosphere.
3I 4.4 B
To what does the term HORIZONTAL
as applied to Wave Polarization refer?
A. This means that the magnetic lines of force
in the radio wave are parallel to the Earth's surface.
B. This means that the electric lines of force
in the radio wave are parallel to the Earth's surface.
C. This means that the electric lines of force
in the radio wave are perpendicular to the Earth's surface.
D. This means that the radio wave will leave
the antenna and radiate Horizontally to the destination.
3I 4.5 B
What electromagnetic wave polarization does a
Cubical Quad Antenna have when the feedpoint
is in the center of a horizontal side?
A. Vertical.
B. Horizontal.
C. Circular.
D. Helical.
3I 4.6 A
What electromagnetic wave polarization does a
Cubical Quad Antenna have when the feedpoint
is in the center of a vertical side?
A. Vertical.
B. Horizontal.
C. Circular.
D. Helical.
3I 4.7 B
What electromagnetic polarization does a Cubical Quad
Antenna have when all sides are at 45 degrees to the
Earth's surface and the feedpoint is at the bottom corner?
A. Vertical.
B. Horizontal.
C. Circular.
D. Helical.
3I 4.8 A
What electromagnetic polarization does a Cubical Quad
Antenna have when all sides are at 45 degrees to the
Earth's surface and the feedpoint is at a side corner?
A. Vertical.
B. Horizontal.
C. Circular.
D. Helical.
3I 6.7 D
What is a DIRECTIONAL ANTENNA?
A. An antenna whose parasitic elements
are all constructed to be directors.
B. An antenna that radiates in direct Line of Sight
propagation, but not skywave or skip propagation.
C. An antenna permanently mounted so
as to radiate in only one direction.
D. An antenna that radiates more strongly
in some directions than others.
3I 8.1 D
What is meant by the term STANDING WAVE RATIO?
A. The ratio of forward and reflected
inductance on a feed line.
B. The ratio of forward and reflected
resistances on a feed line.
C. The ratio of forward and reflected
impedances on a feed line.
D. The ratio of forward and reflected
voltages on a feed line.
3I 8.2 A
What is meant by the term FORWARD POWER?
A. The power traveling from the transmitter to the antenna.
B. The power radiated from the front of the antenna.
C. The power produced during the positive half of the RF cycle.
D. The power used to drive a linear apmlifier.
3I 8.3 B
What is meant by the term REFLECTED POWER?
A. The power radiated from the back of the antenna.
B. The power returned to the transmitter from the antenna.
C. The power produced during the negative half of the RF cycle.
D. The power reflected to the transmitter
site by buildings and trees.
3I 9.1 A
What is STANDING WAVE RATIO a measure of?
A. The ratio of maximum to minimum voltage on a line.
B. The ratio of maximum to minimum reactance on a line.
C. The ratio of maximum to minimum resistance on a line.
D. The ratio of maximum to minimum sidebands on a line.
3I 9.2 D
What happens to the power loss in an unbalanced
feed line as the Standing Wave Ratio increases?
A. It is unpredictable.
B. It becomes nonexistent.
C. It decreases.
D. It increases.
3I 10.1 D
What is a BALANCED LINE?
A. Feed line with one conductor connected to ground.
B. Feed line with both conductors connected
to ground to balance out harmonics.
C. Feed line with the outer conductor
connected to ground at even intervals
D. Feed line with neither conductor connected to ground.
3I 10.2 B
What is a BALANCED ANTENNA?
A. A symetrical antenna with one side
of the feedpoint connected to ground.
B. An antenna (or a driven element in an array)
that is symetrical about the feed point.
C. A symetrical antenna with both sides of the feed
point connected to ground to balance out harmonics.
D. An antenna designed to be mounted in the center.
3I 10.3 C
What is an UNBALANCED LINE?
A. Feed line with neither conductor connected to ground.
B. Feed line with both conductors connected
to ground to balance out harmonics.
C. Feed line with one conductor connected to ground.
D. Feed line with the outer conductor
connected to ground at uneven intervals
3I 10.4 A
What is an UNBALANCED ANTENNA?
A. An antenna (or a driven element in an array)
that is not symetrical about the feed point.
B. A symetrical antenna having neither
half connected to ground.
C. An antenna (or a driven element in an array)
that is symetrical about the feed point.
D. A symetrical antenna with both halves coupled
to ground at uneven intervals to balance out harmonics.
3I 11.3 D
What type of feed line is best suited to
operating at a high Standing Wave Ratio?
A. Coaxial cable.
B. Twisted pair.
C. Flat ribbon "Twin Lead."
D. Parallel Open Wire Line.
3I 11.5 B
What is the general relationship between frequencies
passing through a Feed Line and the losses in the Feed Line?
A. Loss is independent of frequency.
B. Loss increases with increasing frequency.
C. Loss decreases with increasing frequency.
D. There is no predictable relationship.
3I 11.6 C
What happens to RF energy not delivered to
the antenna by a lossy Coaxial Feed Line?
A. It is radiated by the feed line.
B. It is returned to the transmitter's chassis ground.
C. Some of it is dissipated as heat
in the conductors and dielectric.
D. It is canceled because of the voltage ratio of
forward power to reflected power in the feed line.
3I 11.9 A
As the operating frequency decreases, what
happens to conductor losses in a feed line?
A. The losses decreases.
B. The losses increases.
C. The losses remains the same.
D. The losses become infinite.
3I 11.11 B
As operating frequency increases, what
happens to conductor losses in a feed line?
A. The losses decreases.
B. The losses increase.
C. The losses remains the same.
D. The losses decreases to zero.
3I 12.3 D
What device can be installed on a Balanced Antenna
so that it can be fed through a Coaxial Cable?
A. A triaxial transformer.
B. A wavetrap.
C. A loading Coil.
D. A balun.
3I 12.4 B
What is a BALUN?
A. A device that can be used to convert an antenna designed
to be fed at the center so that it may be fed at one end.
B. A device that may be installed on a Balanced Antenna so
that it may be fed with unbalanced feed line.
C. A device that can be installed on an antenna to produce
Horizontally Polarized or Vertically Polarized waves.
D. A device used to allow an antenna to
operate on more than one band.
--------------------------------------------------
End of Subelement 3AI.