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- FCC Technician Exam Question Pool. Subelement 3AI.
- Antennas and Feed Lines. 3 Questions.
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-
- 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.
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- End of Subelement 3AI.
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