3D1X3 CDC Volume 2 Ure
The second one lol.
Questions and Answers
- 1.
(201) Equipment used for generating, amplifying, and transmitting RF carrier is collectively called
- A.
A receiver.
- B.
An antenna.
- C.
A transmitter.
- D.
A transmission line.
Correct Answer
C. A transmitter.Explanation
The correct answer is a transmitter. In the context of generating, amplifying, and transmitting RF carrier signals, a transmitter is the equipment that performs these functions. A receiver is used to capture and process the transmitted signals, while an antenna is used to transmit or receive the signals. A transmission line is a medium that carries the signals between the transmitter and the antenna. Therefore, the equipment used for generating, amplifying, and transmitting RF carrier signals is collectively called a transmitter.Rate this question:
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- 2.
(201) What basic receiver function involves having the transmitted electromagnetic wave pass through the receive antenna in such a manner as to induce a voltage in the antenna?
- A.
Reproduction.
- B.
Reception.
- C.
Detection.
- D.
Selection.
Correct Answer
B. Reception.Explanation
Reception is the basic receiver function that involves the transmitted electromagnetic wave passing through the receive antenna in such a manner as to induce a voltage in the antenna. This voltage is then processed and decoded to extract the information carried by the wave. The other options, reproduction, detection, and selection, do not accurately describe this process.Rate this question:
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- 3.
(201) The ability to reproduce the input signal accurately is the characteristics of the receiver's
- A.
Fidelity.
- B.
Capacity.
- C.
Sensitivity.
- D.
Selectivity.
Correct Answer
A. Fidelity.Explanation
Fidelity refers to the ability of the receiver to reproduce the input signal accurately. It signifies that the receiver can faithfully reproduce the original signal without any distortion or loss of information. This characteristic is important in ensuring that the receiver can accurately capture and interpret the intended message or data from the input signal. Capacity, sensitivity, and selectivity are not directly related to the accuracy of signal reproduction, making them incorrect choices.Rate this question:
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- 4.
(202) A combination of a transmitter and receiver that is built as a single unit and sharing common tuned circuits is called a
- A.
Transmitter.
- B.
Transceiver.
- C.
Receiver.
- D.
Coupler.
Correct Answer
B. Transceiver.Explanation
A transceiver is a combination of a transmitter and receiver that is built as a single unit and shares common tuned circuits. This allows for the transmission and reception of signals using the same device.Rate this question:
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- 5.
(202) Which of the following cannot be performed by the transceiver's computerized components and micro-circuitry?
- A.
Specific equipment faults.
- B.
Internal equipment tests.
- C.
Internal calibrations.
- D.
Repair itself.
Correct Answer
D. Repair itself.Explanation
The transceiver's computerized components and micro-circuitry are capable of performing specific equipment faults, internal equipment tests, and internal calibrations. However, they are not capable of repairing themselves.Rate this question:
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- 6.
(203) A transmission line that consists of a center conductor placed inside a metal tube functioning as the outer tube is called a
- A.
Flexible coaxial cable.
- B.
Rigid coaxial cable.
- C.
Waveguide.
- D.
Twin lead.
Correct Answer
B. Rigid coaxial cable.Explanation
A transmission line that consists of a center conductor placed inside a metal tube functioning as the outer tube is called a rigid coaxial cable. This type of cable is commonly used in applications where high-frequency signals need to be transmitted with low loss and minimal interference. The rigid structure of the coaxial cable provides better shielding and protection against external electromagnetic interference, making it suitable for long-distance and high-performance communication systems.Rate this question:
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- 7.
(203) Which selection best describes the term "cutoff frequency" when discussing transmission line properties?
- A.
The frequency where XL becomes to low that the signal is shunted.
- B.
The frequency where XC causes the signal to be shunted.
- C.
The lowest frequency that the line can pass successfully.
- D.
The frequency at which standing waves are maximum.
Correct Answer
C. The lowest frequency that the line can pass successfully.Explanation
The term "cutoff frequency" refers to the lowest frequency that a transmission line can successfully pass. This means that any frequency below the cutoff frequency will be attenuated or blocked by the transmission line.Rate this question:
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- 8.
(203) Using figure 1-10, determine the wavelength if the frequency is changed from 150 MHz to 250 MHz.
- A.
12.0 meters.
- B.
3.0 meters.
- C.
1.5 meters.
- D.
1.2 meters.
Correct Answer
D. 1.2 meters.Explanation
The wavelength of a wave can be determined using the formula: wavelength = speed of light / frequency. In this case, the frequency is changed from 150 MHz to 250 MHz. As the frequency increases, the wavelength decreases. Therefore, the wavelength will be shorter at 250 MHz compared to 150 MHz. The correct answer, 1.2 meters, indicates that the wavelength has become shorter.Rate this question:
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- 9.
(203) Using figure 1-10, determine the electrical length if the frequency is changed from 150 MHz to 250 MHz.
- A.
8.33 meters.
- B.
8.33 wavelengths.
- C.
83.3 meters.
- D.
83.3 wavelengths.
Correct Answer
B. 8.33 wavelengths.Explanation
The electrical length of a transmission line is determined by the number of wavelengths it takes for a signal to travel through it. When the frequency is changed from 150 MHz to 250 MHz, the number of wavelengths will remain constant, as the speed of light is constant. Therefore, the electrical length will also remain constant at 8.33 wavelengths.Rate this question:
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- 10.
(203) A nonresonant transmission line is a line
- A.
Having reflected waves.
- B.
Having no reflected waves.
- C.
With maximum voltage across its open termination.
- D.
With maximum voltages across its shorted termination.
Correct Answer
B. Having no reflected waves.Explanation
A nonresonant transmission line refers to a line that does not produce any reflected waves. In other words, all the energy that is sent through the line is effectively transmitted without any portion being reflected back towards the source. This can occur when the line is properly terminated, allowing for maximum power transfer and minimizing any reflections. Therefore, the correct answer is "having no reflected waves."Rate this question:
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- 11.
(203) If a transmission line is terminated in a short
- A.
Current is at maximum and voltage at minimum at the termination.
- B.
Current is at minimum and voltage at maximum at the termination.
- C.
There would be a nominal amount of signal gain.
- D.
The line would be nonresonant.
Correct Answer
A. Current is at maximum and voltage at minimum at the termination.Explanation
When a transmission line is terminated in a short, it means that the line is connected to a load impedance that is very low, causing a reflection of the signal. This reflection causes the current to be at maximum and the voltage to be at minimum at the termination point.Rate this question:
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- 12.
(204) In a basic communication system, what converts radio frequency (RF) energy's current oscillation into electric and magnetic fields of force?
- A.
Antenna.
- B.
Coupler.
- C.
Transmitter.
- D.
Transmission lines.
Correct Answer
A. Antenna.Explanation
An antenna is the component in a communication system that converts radio frequency (RF) energy's current oscillation into electric and magnetic fields of force. It is responsible for transmitting and receiving electromagnetic waves, allowing for the wireless transmission of information. Antennas come in various forms and sizes depending on the specific application and frequency range. They are crucial in enabling wireless communication and are commonly used in radio, television, cellular networks, and other wireless communication systems.Rate this question:
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- 13.
(204) The concept that alternation current (AC) changes in magnitude and reverses its direction during each cycle is
- A.
An unproven hypothesis.
- B.
The definition of propagation.
- C.
What makes radio transmission possible.
- D.
What led to the discovery of direct current.
Correct Answer
C. What makes radio transmission possible.Explanation
The concept that alternating current (AC) changes in magnitude and reverses its direction during each cycle is what makes radio transmission possible. AC is used in radio transmission because it can be easily converted to different frequencies, allowing for the transmission of information through electromagnetic waves. This concept is not an unproven hypothesis, the definition of propagation, or what led to the discovery of direct current.Rate this question:
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- 14.
(205) If the electric field component travels in a plane perpendicular to the Earth's surface, the radio wave is
- A.
Magnetically polarized.
- B.
Horizontally polarized.
- C.
Circularly polarized.
- D.
Vertically polarized.
Correct Answer
D. Vertically polarized.Explanation
When the electric field component of a radio wave travels in a plane perpendicular to the Earth's surface, the wave is vertically polarized. This means that the electric field oscillates up and down in a vertical direction. The other options can be ruled out because they describe different orientations of the electric field component.Rate this question:
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- 15.
(205) What types of polarization do satellite terminals transmit and receive?
- A.
Transmit horizontal and receive vertical polarizations.
- B.
Transmit vertical and receive horizontal polarizations.
- C.
Transmit right hand and receive left hand circular polarizations.
- D.
Transmit left hand and receive right hand circular polarizations.
Correct Answer
C. Transmit right hand and receive left hand circular polarizations.Explanation
Satellite terminals transmit and receive signals using right hand and left hand circular polarizations. Circular polarization is used in satellite communication because it provides better resistance to signal degradation caused by atmospheric conditions and other interference. Transmitting right hand circular polarization and receiving left hand circular polarization allows for efficient signal transmission and reception between the satellite and the terminal.Rate this question:
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- 16.
(206) What measurement is used to determine whether an antenna is resonant at a particular frequency?
- A.
Distortion.
- B.
Standing wave ratio.
- C.
Signal-to-noise ratio.
- D.
Percent of modulation.
Correct Answer
B. Standing wave ratio.Explanation
The measurement used to determine whether an antenna is resonant at a particular frequency is the standing wave ratio. The standing wave ratio (SWR) is a measure of how well the antenna is matched to the transmission line and the desired frequency. A low SWR indicates a good match and efficient transfer of power, while a high SWR indicates a poor match and potential signal loss. Therefore, the SWR is an important measurement in antenna tuning and optimization.Rate this question:
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- 17.
(206) The ability of an antenna to both receive and transmit equally well is known as the antenna's
- A.
Bandwidth.
- B.
Resonance.
- C.
Reciprocity.
- D.
Effectiveness.
Correct Answer
C. Reciprocity.Explanation
Reciprocity refers to the ability of an antenna to perform equally well in both receiving and transmitting signals. It means that the antenna's characteristics, such as gain and radiation pattern, remain the same regardless of whether it is used for receiving or transmitting. This property is important in many applications, as it allows for efficient and reliable communication. Bandwidth refers to the range of frequencies over which an antenna can operate effectively, resonance refers to the natural frequency at which an antenna resonates, and effectiveness is a general term that does not specifically describe the antenna's ability to both receive and transmit.Rate this question:
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- 18.
(206) The standard used to measure the radiating effectiveness (gain) of an antenna system is the
- A.
Marconi antenna.
- B.
Isotropic antenna.
- C.
Hertz antenna.
- D.
Whip antenna.
Correct Answer
B. Isotropic antenna.Explanation
The correct answer is isotropic antenna. An isotropic antenna is a theoretical antenna that radiates power uniformly in all directions. It is used as a reference antenna to compare the gain of other antennas. The gain of an antenna is a measure of its ability to focus the radiated power in a specific direction. By comparing the gain of an antenna system to that of an isotropic antenna, we can determine how effectively the antenna system radiates power in a specific direction.Rate this question:
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- 19.
(206) What does the effectiveness of an entire transmitting and receiving system depend largely upon?
- A.
Impedance matching.
- B.
Antenna distance.
- C.
Antenna properties.
- D.
Line characteristics.
Correct Answer
A. Impedance matching.Explanation
The effectiveness of an entire transmitting and receiving system largely depends on impedance matching. Impedance matching refers to the process of ensuring that the impedance of the source (transmitter) matches the impedance of the load (antenna). When the impedance is matched, maximum power transfer occurs, resulting in efficient transmission and reception of signals. Antenna distance, antenna properties, and line characteristics can also affect the performance of the system, but impedance matching is the key factor in optimizing the system's effectiveness.Rate this question:
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- 20.
(207) Which antenna radiates radio energy in a circular pattern?
- A.
Omnidirectional.
- B.
Unidirectional.
- C.
Bidirectional.
- D.
Directional.
Correct Answer
A. Omnidirectional.Explanation
An omnidirectional antenna radiates radio energy in a circular pattern, meaning it covers a full 360 degrees around its axis. This type of antenna is designed to provide equal coverage in all directions, making it ideal for applications where the signal needs to reach multiple locations or devices without the need for precise aiming or alignment. Omnidirectional antennas are commonly used in Wi-Fi routers, cell towers, and broadcasting systems.Rate this question:
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- 21.
(207) Which antenna type is usually used on long-range, point-to-point circuits where the concentrated radio energy is needed for circuitry reliability?
- A.
Omnidirectional.
- B.
Unidirectional.
- C.
Bidirectional.
- D.
Circular.
Correct Answer
B. Unidirectional.Explanation
Unidirectional antennas are usually used on long-range, point-to-point circuits where concentrated radio energy is needed for circuitry reliability. Unlike omnidirectional antennas that radiate radio waves in all directions, unidirectional antennas focus the radio energy in a specific direction, allowing for a stronger and more reliable signal over long distances. This makes them ideal for long-range communication where a concentrated and reliable signal is necessary.Rate this question:
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- 22.
(208) Ungrounded lengths of wire specifically designed to be either a half-wavelength or more than a full wavelength long is called a
- A.
Reflector.
- B.
Hertz antenna.
- C.
Marconi antenna.
- D.
Vertical monopole.
Correct Answer
B. Hertz antenna.Explanation
The correct answer is Hertz antenna. A Hertz antenna is an ungrounded length of wire that is specifically designed to be either a half-wavelength or more than a full wavelength long. It is named after Heinrich Hertz, who first demonstrated the existence of radio waves. This type of antenna is commonly used in radio communication systems.Rate this question:
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- 23.
(209) A long-wire's takeoff angle depends on the antenna's
- A.
Length.
- B.
Directivity.
- C.
Front-to-back ratio.
- D.
Standing wave ratio.
Correct Answer
A. Length.Explanation
The takeoff angle of a long-wire antenna is determined by its length. The longer the antenna, the lower the takeoff angle, which means the signal is radiated closer to the ground. This can be advantageous for long-distance communication as it allows the signal to travel further before encountering obstacles such as buildings or hills. Therefore, the length of the antenna directly affects its takeoff angle and the effectiveness of the communication.Rate this question:
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- 24.
(209) All antennas used in satellite communications are designed to be
- A.
Circular directional.
- B.
Omnidirectional.
- C.
Bidirectional.
- D.
Directional.
Correct Answer
D. Directional.Explanation
The correct answer is "directional". This means that all antennas used in satellite communications are designed to transmit and receive signals in a specific direction. They are able to focus their energy in a narrow beam, allowing for better signal strength and reception. This is important in satellite communications as it allows for more efficient and reliable communication between the satellite and the ground station.Rate this question:
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- 25.
(209) A commmon satellite antenna is the
- A.
Whip.
- B.
Discone.
- C.
Parabolic.
- D.
Long-wire.
Correct Answer
C. Parabolic.Explanation
The correct answer is parabolic. A parabolic satellite antenna is commonly used to receive and transmit signals from satellites. The shape of the parabolic dish allows it to focus the signals onto a receiver or transmitter at its focal point, improving the efficiency and quality of the communication. This type of antenna is widely used for satellite TV reception and satellite internet services.Rate this question:
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- 26.
(209) A helical antenna radiates a signal with what type of polarization?
- A.
Horizontal.
- B.
Vertical.
- C.
Circular.
- D.
Linear.
Correct Answer
C. Circular.Explanation
A helical antenna radiates a signal with circular polarization because the helical shape of the antenna causes the electromagnetic waves to rotate as they propagate. This means that the electric field vector of the signal rotates in a circular pattern as it travels, rather than being fixed in a horizontal or vertical orientation. Circular polarization is useful in certain applications, such as satellite communication, because it allows for better signal reception regardless of the orientation of the receiving antenna.Rate this question:
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- 27.
(210) Aircraft antennas are housed
- A.
Inside nonconductive radomes mounted outside or flush with the fuselage.
- B.
Inside conductive radomes mounted outside or flush with the fuselage.
- C.
Outside nonconductive radomes mounted outside the fuselage.
- D.
Inside conductive radomes mounted flush with the fuselage.
Correct Answer
A. Inside nonconductive radomes mounted outside or flush with the fuselage.Explanation
Aircraft antennas are housed inside nonconductive radomes to protect them from external elements and provide a streamlined shape. These radomes are mounted outside or flush with the fuselage to minimize interference with the antenna's signal reception and transmission. Using nonconductive materials helps to prevent signal loss and maintain the efficiency of the antenna system.Rate this question:
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- 28.
(210) In airborne antenna applications for frequencies in the upper portion of the HF band, what vertical angles are used for multi-hop, long distance transmission?
- A.
90 and 180 degrees.
- B.
60 and 90 degrees.
- C.
30 and 60 degrees.
- D.
5 and 30 degrees.
Correct Answer
D. 5 and 30 degrees.Explanation
In airborne antenna applications for frequencies in the upper portion of the HF band, multi-hop, long distance transmission requires specific vertical angles. The correct answer of 5 and 30 degrees suggests that these angles are used for such transmission.Rate this question:
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- 29.
(210) What determines an antenna's location and orientation on the aircraft?
- A.
Antennas always require a 360 degree radiating pattern.
- B.
The type of aircraft propulsion and power system.
- C.
Antennas are always mounted on top of the fuselage.
- D.
Optimizing the antenna's radiating pattern for its application.
Correct Answer
D. Optimizing the antenna's radiating pattern for its application.Explanation
The correct answer is "Optimizing the antenna's radiating pattern for its application." This answer explains that the location and orientation of an antenna on an aircraft is determined by optimizing its radiating pattern for its specific application. This means that the antenna is positioned and aligned in a way that allows it to efficiently transmit and receive signals based on the specific needs and requirements of the aircraft's communication or navigation system.Rate this question:
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- 30.
(210) Which type of airborne antenna can be designed into any part of an aerospace vehicle's surface, so that it does not upset its aerodynamic properties?
- A.
Fixed blade.
- B.
Conformal.
- C.
Probe tip.
- D.
Whip.
Correct Answer
B. Conformal.Explanation
A conformal airborne antenna can be designed into any part of an aerospace vehicle's surface without affecting its aerodynamic properties. This means that the antenna can be seamlessly integrated into the vehicle's structure, allowing for efficient communication without compromising the vehicle's performance or stability.Rate this question:
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- 31.
(211) In selecting an antenna for a circuit, what is the first thing to look at?
- A.
Type of propagation.
- B.
Selecting the antenna.
- C.
Determine the distance.
- D.
Finding the operating frequency.
Correct Answer
A. Type of propagation.Explanation
When selecting an antenna for a circuit, the first thing to look at is the type of propagation. Propagation refers to how the electromagnetic waves travel from the antenna to the receiver. Different types of propagation, such as line-of-sight or ground wave, require different types of antennas to effectively transmit and receive signals. Therefore, understanding the type of propagation is crucial in selecting the appropriate antenna for the circuit.Rate this question:
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- 32.
(212) Which object has the greatest effect on an antenna?
- A.
Sun.
- B.
Earth.
- C.
Operator.
- D.
Ionosphere.
Correct Answer
B. Earth.Explanation
The Earth has the greatest effect on an antenna because it is the largest and closest object to the antenna. The Earth's surface and atmosphere can cause signal reflections, refractions, and absorptions, which can affect the performance and reception of the antenna. The Earth also acts as a ground plane for the antenna, providing a reference point for the antenna's radiation pattern.Rate this question:
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- 33.
(212) Where is the most challenging location for a radio frequency (RF) transmission systems technician to establish and operate a radio station from?
- A.
Amazon jungle.
- B.
North Pole.
- C.
Sahara desert.
- D.
Sierra Nevada mountains.
Correct Answer
A. Amazon jungle.Explanation
The Amazon jungle is the most challenging location for a radio frequency (RF) transmission systems technician to establish and operate a radio station from. The dense vegetation and remote location make it difficult to set up the necessary infrastructure for transmitting and receiving signals. The thick foliage can obstruct the radio waves, resulting in poor signal strength and coverage. Additionally, the lack of infrastructure and limited access to power sources make it challenging to maintain and operate the radio station effectively in the Amazon jungle.Rate this question:
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- 34.
(212) With a mountain between you and the distant end, which anrenna is more effective?
- A.
Whip.
- B.
Dipole.
- C.
Discone.
- D.
Near-vertical incidence skywave.
Correct Answer
D. Near-vertical incidence skywave.Explanation
The near-vertical incidence skywave antenna is more effective when there is a mountain between you and the distant end. This type of antenna is specifically designed to transmit and receive signals that are reflected off the ionosphere at very low angles. This allows the signals to penetrate obstacles like mountains and reach the desired destination effectively. The whip, dipole, and discone antennas are not optimized for this scenario and may experience more signal loss or interference.Rate this question:
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- 35.
(213) Direct waves are radio waves that travel
- A.
Long distances with few interruptions.
- B.
From point to point along the earth's surface.
- C.
Through the air in a straight line.
- D.
No more than 20 miles to the receive antenna.
Correct Answer
C. Through the air in a straight line.Explanation
Direct waves are radio waves that travel through the air in a straight line. Unlike other types of waves, such as ground waves or sky waves, direct waves do not require any reflection or refraction to reach their destination. They are able to travel in a straight line from the transmitting antenna to the receiving antenna without any interruptions. This characteristic allows direct waves to be used for long-distance communication, as they can travel over large distances without significant loss of signal strength.Rate this question:
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- 36.
(213) Radio waves that travel near the earth's surface are called
- A.
Earth waves.
- B.
Global waves.
- C.
Ground waves.
- D.
Terrestrial waves.
Correct Answer
C. Ground waves.Explanation
Radio waves that travel near the earth's surface are called ground waves. These waves propagate by hugging the surface of the earth and are able to follow its curvature. Ground waves are important for long-distance communication as they can travel for hundreds of miles and are not easily affected by obstacles such as buildings or hills. They are commonly used for broadcasting purposes, such as AM radio stations.Rate this question:
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- 37.
(213) Sky wave transmission is used for which type of communcations?
- A.
Long distance.
- B.
Subterrestrial.
- C.
Atmospheric.
- D.
Line of sight.
Correct Answer
A. Long distance.Explanation
Sky wave transmission refers to the propagation of radio waves in the Earth's atmosphere, where the waves are reflected back to the Earth's surface by the ionosphere. This type of transmission is used for long-distance communications because the radio waves can travel over large distances by bouncing off the ionosphere. It is particularly useful for communication over large bodies of water or across mountainous terrain where line-of-sight communication is not possible. Therefore, the correct answer is "Long distance."Rate this question:
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- 38.
(214) The path that undergoes a 180 degree phase shift is a
- A.
Ground-reflected path.
- B.
Surface path.
- C.
Direct path.
- D.
Sky path.
Correct Answer
A. Ground-reflected path.Explanation
A ground-reflected path refers to a signal that bounces off the ground before reaching the receiver. In this case, the path undergoes a 180 degree phase shift, which means that the signal is inverted when it reaches the receiver. This is consistent with the concept of a ground-reflected path, where the signal is reflected off the ground and experiences a phase shift of 180 degrees.Rate this question:
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- 39.
(214) Which gives sky wave propagation its ability to communicate beyond the optical line-of-sight (LOS)?
- A.
Refraction.
- B.
Reflection.
- C.
Earth's conductivity.
- D.
Atmospheric charge.
Correct Answer
A. Refraction.Explanation
Refraction is the correct answer because it is the bending of radio waves as they pass through different layers of the atmosphere. This bending allows the waves to follow the curvature of the Earth and reach beyond the optical line-of-sight. Reflection, Earth's conductivity, and atmospheric charge do not contribute to sky wave propagation in the same way as refraction.Rate this question:
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- 40.
(214) Frequencies higher than the cricical frequency are
- A.
Returned to earth.
- B.
Passed into space.
- C.
The most desirable.
- D.
Refracted by the F2 layer.
Correct Answer
B. Passed into space.Explanation
Frequencies higher than the critical frequency are passed into space. This means that they are not reflected or refracted back to Earth. The critical frequency is the maximum frequency that can be reflected back to Earth by the ionosphere. Frequencies higher than this critical frequency are not able to be reflected and instead continue to propagate into space.Rate this question:
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- 41.
(214) In high frequency (HF) communications, the lowest frequency that arrives at the distant receiver on 90 percent of the undistubred days of the month is called the
- A.
Maximum usable frequency (MUF).
- B.
Lowest usable frequency (LUF).
- C.
Operating frequency.
- D.
Critical frequency.
Correct Answer
B. Lowest usable frequency (LUF).Explanation
The lowest usable frequency (LUF) refers to the lowest frequency that consistently arrives at the distant receiver on 90 percent of undisturbed days of the month in high frequency (HF) communications. It is the frequency that can reliably be used for communication over long distances. The maximum usable frequency (MUF) is the highest frequency that can be used for reliable communication, while the operating frequency is the frequency at which the HF communication system is currently operating. The critical frequency is the frequency at which the ionosphere becomes too dense for radio waves to penetrate.Rate this question:
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- 42.
(214) The abbreviation FOT is derived from the term
- A.
Outbound traffic frequency.
- B.
Optimum tropospheric frequency.
- C.
Frequency of optimum transmission.
- D.
Frequency of outbound transmission.
Correct Answer
C. Frequency of optimum transmission.Explanation
The abbreviation FOT is derived from the term "frequency of optimum transmission." This suggests that FOT refers to the specific frequency at which transmission is most effective or efficient. It is not related to outbound traffic frequency or frequency of outbound transmission, as these options focus on the direction of transmission rather than the quality or effectiveness of the transmission. Similarly, it is not related to optimum tropospheric frequency, which is not mentioned in the question.Rate this question:
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- 43.
(214) Magneton splitting creates two waves called
- A.
Direct and indirect.
- B.
Ordinary and abnormal.
- C.
In-phase and out-of-phase.
- D.
Ordinary and extraordinary.
Correct Answer
D. Ordinary and extraordinary.Explanation
Magneton splitting refers to the phenomenon where a single spectral line splits into two or more lines in the presence of a magnetic field. In this case, the splitting results in two waves, which are referred to as ordinary and extraordinary waves. The ordinary wave propagates parallel to the magnetic field and experiences a refractive index that is independent of the direction of polarization. On the other hand, the extraordinary wave propagates perpendicular to the magnetic field and experiences a refractive index that depends on the direction of polarization. Therefore, the correct answer is ordinary and extraordinary.Rate this question:
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- 44.
(214) What occurs when a transmitted signal travels over two or more separate paths during transmission?
- A.
Skip effects.
- B.
Modulation.
- C.
Multipathing.
- D.
Magneton splitting.
Correct Answer
C. Multipathing.Explanation
Multipathing occurs when a transmitted signal travels over two or more separate paths during transmission. This can happen when the signal reflects off of obstacles or bounces off of different surfaces, resulting in multiple versions of the signal reaching the receiver. Multipathing can cause signal distortion, interference, and fading, which can degrade the quality and reliability of the received signal.Rate this question:
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- 45.
(215) What is the recombination process dependant upon?
- A.
Season.
- B.
Time of day.
- C.
Regular variation.
- D.
Irregular variations.
Correct Answer
B. Time of day.Explanation
The recombination process is dependent upon the time of day. This suggests that the process of recombination, which involves the exchange of genetic material between chromosomes, occurs at specific times during the day. It implies that the recombination process is regulated by biological mechanisms that are influenced by the circadian rhythm or other time-dependent factors.Rate this question:
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- 46.
(215) Which layer of the ionosphere is most important to high frequency (HF) communications?
- A.
D.
- B.
E.
- C.
F.
- D.
Topside.
Correct Answer
C. F.Explanation
The topside layer of the ionosphere is the most important for high frequency (HF) communications. This is because it is the highest region of the ionosphere, closest to outer space, and it allows for long-distance communication by reflecting HF radio waves back to Earth. The topside layer also has the highest electron density, which enhances its ability to reflect HF signals.Rate this question:
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- 47.
(215) During what season do we have the wider range of critical frequencies and less absorption of all frequencies?
- A.
Fall.
- B.
Winter.
- C.
Spring.
- D.
Summer.
Correct Answer
B. Winter.Explanation
In winter, the air is colder and denser, which allows sound waves to travel more efficiently. This leads to a wider range of critical frequencies, meaning that a greater variety of sounds can be heard. Additionally, there is less absorption of all frequencies in winter, as the cold air does not absorb sound waves as much as warmer air does. Therefore, winter is the season when we have the wider range of critical frequencies and less absorption of all frequencies.Rate this question:
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- 48.
(215) Sunspots are disturbances
- A.
In the sun's atmosphere.
- B.
On the sun's surface.
- C.
In the ionosphere.
- D.
Beneath the sun's surface.
Correct Answer
B. On the sun's surface.Explanation
Sunspots are dark areas on the sun's surface that appear to be cooler than the surrounding areas. They are caused by intense magnetic activity, which inhibits the flow of heat from the sun's interior to its surface. Therefore, sunspots are located on the sun's surface.Rate this question:
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- 49.
(216) For communications purposes, the useable frequency spectrum ranges from
- A.
3 hertz (Hz) to 300 gigahertz (GHz).
- B.
300 Hz to 300 GHz.
- C.
3000 Hz to 3000 GHz.
- D.
30 megahertz (MHz) to 300 MHz.
Correct Answer
A. 3 hertz (Hz) to 300 gigahertz (GHz).Explanation
The correct answer is 3 hertz (Hz) to 300 gigahertz (GHz). This range is considered the useable frequency spectrum for communications purposes. It includes frequencies from the very low end at 3 Hz to the very high end at 300 GHz. This range covers a wide variety of frequencies that are used for different types of communication, including radio waves, microwaves, and infrared waves.Rate this question:
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- 50.
(216) What U.S. government agency divides the radio frequency (RF) spectrum into different bands?
- A.
Federal Aviation Agency.
- B.
American National Standard Institute.
- C.
Federal Communications Commission.
- D.
Institute of Electrical & Electronics Engineers, Inc.
Correct Answer
C. Federal Communications Commission.Explanation
The Federal Communications Commission (FCC) is the U.S. government agency responsible for dividing the radio frequency (RF) spectrum into different bands. The FCC regulates and oversees communication technologies, including radio, television, wire, satellite, and cable. They allocate different frequency bands to different services and users to ensure efficient and effective use of the RF spectrum.Rate this question:
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Mar 20, 2023Quiz Edited by
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Jul 20, 2011Quiz Created by
Ihatecdc
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