3D1X3 CDC Volume 1 Ure
Read the damn title also jones.
- 1.
(001) What reason for modulation involves modulating low frequency signals for transmission over long distances?
- A.
Spectrum conservation
- B.
Channel allocation
- C.
Ease of radiation
- D.
Companding
Correct Answer
C. Ease of radiationExplanation
Modulating low frequency signals for transmission over long distances improves the ease of radiation. This means that it is easier to transmit the modulated signals over long distances without significant loss or degradation. Modulation allows for the efficient use of the available bandwidth and helps to overcome the limitations of long-distance transmission, such as signal attenuation and interference. By modulating the low frequency signals, they can be easily transmitted and received over long distances, ensuring effective communication.Rate this question:
-
- 2.
(001) What are the three general categories used to produce modulation in radio frequency (RF) transmission today?
- A.
Binary amplitude shift keying, frequency shift keying, and phase shift keying.
- B.
Pulse amplitude, pulse width, and pulse position.
- C.
Amplitude, frequency, and phase.
- D.
Analog, digital, and shift keying.
Correct Answer
C. Amplitude, frequency, and phase.Explanation
The three general categories used to produce modulation in radio frequency (RF) transmission today are amplitude, frequency, and phase. These categories refer to the different ways in which the RF signal can be modified to carry information. Amplitude modulation (AM) involves varying the amplitude of the RF signal to encode information. Frequency modulation (FM) involves varying the frequency of the RF signal. Phase modulation (PM) involves varying the phase of the RF signal. These modulation techniques are widely used in RF communication systems to transmit and receive information.Rate this question:
-
- 3.
(002) When the modulating signal and carrier signal are combined within a modulator, the output signal contains a/an
- A.
Modulating signal, upper sideband, lower sideband.
- B.
Carrier, upper sideband, and lower sideband.
- C.
Upper sideband and modulating signal.
- D.
Carrier and modulating signal.
Correct Answer
B. Carrier, upper sideband, and lower sideband.Explanation
When the modulating signal and carrier signal are combined within a modulator, the output signal contains the carrier signal, as well as the upper sideband and lower sideband. The carrier signal is the original unmodulated signal, while the upper and lower sidebands are the result of the modulation process.Rate this question:
-
- 4.
(002) If a carrier frequency of 1 MHz and a modulating tone of 10 kHz goes to the modulator, the output signal includes
- A.
1.01 MHz, 1 MHz, and 0.99 MHz.
- B.
1.1 MHz, 1 MHz, and 0.9 MHz.
- C.
1.11 MHz, 1 MHz, 0.99 MHz.
- D.
1.111 MHz, 1 MHz, 0.999 MHz
Correct Answer
A. 1.01 MHz, 1 MHz, and 0.99 MHz.Explanation
When a carrier frequency of 1 MHz and a modulating tone of 10 kHz are inputted into the modulator, the output signal will include the carrier frequency (1 MHz), the sum of the carrier and modulating frequencies (1.01 MHz), and the difference between the carrier and modulating frequencies (0.99 MHz). This is due to the process of modulation, where the modulating signal is used to vary the amplitude, frequency, or phase of the carrier signal.Rate this question:
-
- 5.
(002) If the modulating audio signal is 10kHz wide, what is the bandwidth of the transmitted amplitude modulated signal?
- A.
5 kHz
- B.
10 kHz
- C.
15 kHz
- D.
20 kHz
Correct Answer
D. 20 kHzExplanation
The bandwidth of an amplitude modulated signal is determined by the sum of the highest frequency in the modulating signal and the highest frequency in the carrier signal. In this case, the modulating audio signal is 10 kHz wide, so the highest frequency in the modulating signal is 10 kHz. Assuming the carrier signal has a frequency of 0 Hz, the bandwidth of the transmitted amplitude modulated signal would be 10 kHz + 0 Hz = 10 kHz. Therefore, the correct answer is 10 kHz, not 20 kHz as stated in the given answer.Rate this question:
-
- 6.
(002) The bandwidth of an amplitude modulated signal is
- A.
Two times the modulating signal.
- B.
The same as the modulating signal.
- C.
Determined by modulation index.
- D.
Defined in terms of maximum amount of modulation.
Correct Answer
A. Two times the modulating signal.Explanation
The bandwidth of an amplitude modulated signal is two times the modulating signal. This means that the range of frequencies occupied by the modulated signal is twice the range of frequencies present in the original modulating signal. This is because in amplitude modulation, the sidebands are created above and below the carrier frequency, resulting in the doubling of the bandwidth.Rate this question:
-
- 7.
(002) The amount of effect or change that the intelligence has on the carrier in an amplitude modulated signal is expressed as the
- A.
Percent of modulation.
- B.
Modulation index.
- C.
Bandwidth.
- D.
Deviation.
Correct Answer
A. Percent of modulation.Explanation
The amount of effect or change that the intelligence has on the carrier in an amplitude modulated signal is expressed as the percent of modulation. This term refers to the percentage of variation in the amplitude of the carrier signal caused by the modulation. It indicates the strength or intensity of the modulation and is commonly used to measure the quality or fidelity of the modulated signal.Rate this question:
-
- 8.
(002) Which statement concerning bandwidth is true?
- A.
Overmodulating increases bandwidth due to the production of harmonics.
- B.
Undermodulating increases bandwidth due to the production of harmonics.
- C.
Overmodulating increases bandwidth due to the output's increased amplitude.
- D.
Undermodulating increases bandwidth due to the output's increased amplitude.
Correct Answer
A. Overmodulating increases bandwidth due to the production of harmonics.Explanation
Overmodulating refers to the process of increasing the amplitude of a signal beyond its normal limits. This causes the signal to produce harmonics, which are additional frequencies that are multiples of the original signal frequency. These harmonics increase the overall bandwidth of the signal. Therefore, overmodulating increases bandwidth due to the production of harmonics.Rate this question:
-
- 9.
(002) Reducing modulation to less than 100 percent gives
- A.
More total power.
- B.
A reduction in carrier power.
- C.
No reduction in carrier power.
- D.
A reduction in carrier and sideband power.
Correct Answer
C. No reduction in carrier power.Explanation
When modulation is reduced to less than 100 percent, it means that the amplitude of the carrier signal is not fully varied by the modulating signal. In this case, the carrier power remains constant and is not reduced. The reduction in modulation only affects the amplitude of the sidebands, which carry the modulating signal information. Therefore, the correct answer is that there is no reduction in carrier power.Rate this question:
-
- 10.
(003) In frequency modulation (FM), the amount of oscillator frequency change is
- A.
Inversely proportional to the amplitude of the modulating signal.
- B.
Directly proportional to the amplitude of the modulating signal.
- C.
Inversely proportional to the phase of the modulating signal.
- D.
Directly proportional to the phase of the modulating signal.
Correct Answer
B. Directly proportional to the amplitude of the modulating signal.Explanation
In frequency modulation (FM), the amount of oscillator frequency change is directly proportional to the amplitude of the modulating signal. This means that as the amplitude of the modulating signal increases, the frequency deviation of the carrier signal also increases. This relationship allows for the encoding of information in the form of variations in frequency, which is the basis of FM modulation.Rate this question:
-
- 11.
(003) In frequency modulation (FM), what is considered a significant sideband?
- A.
Sidebands containing at least 1 percent of the total transmitted power.
- B.
Sidebands containing at least 3 percent of the total transmitted power.
- C.
Sidebands containing at least 10 percent of the total transmitted power.
- D.
Sidebands containing at least 0.1 percent of the total transmitted power.
Correct Answer
A. Sidebands containing at least 1 percent of the total transmitted power.Explanation
In frequency modulation (FM), significant sidebands are considered to be those that contain at least 1 percent of the total transmitted power. This means that the sidebands must have a substantial amount of power in order to be considered significant in FM modulation.Rate this question:
-
- 12.
(003) What is the formula to find the modulating index?
- A.
Deviation divided by frequency of modulation.
- B.
Deviation times frequency of modulation.
- C.
Sideband divided by carrier frequency.
- D.
Sideband times carrier frequency.
Correct Answer
A. Deviation divided by frequency of modulation.Explanation
The formula to find the modulating index is deviation divided by the frequency of modulation. This formula is used to calculate the extent of modulation in a signal. The modulating index represents the ratio of the maximum deviation of the carrier wave to the frequency of the modulating signal. It helps determine the bandwidth and efficiency of the modulation process.Rate this question:
-
- 13.
(004) In phase modulation (PM), the carrier's
- A.
Phase is shifted at the rate of the modulating signal.
- B.
Phase shifted with the phase of the modulating signal.
- C.
Amplitude is shifted at the rate of the modulating signal.
- D.
Amplitude is shifted with the phase of the modulating signal.
Correct Answer
A. Phase is shifted at the rate of the modulating signal.Explanation
In phase modulation (PM), the phase of the carrier signal is shifted at the rate of the modulating signal. This means that the instantaneous phase of the carrier signal is changed according to the variations in the modulating signal. The amount of phase shift is directly proportional to the amplitude of the modulating signal. This allows for the encoding of information in the phase of the carrier signal, making phase modulation a useful technique in communication systems.Rate this question:
-
- 14.
(004) What is the advantage of adding more phase shifts?
- A.
Easier detection.
- B.
Smaller bit error rate.
- C.
Better signal-to-noise ratio.
- D.
Higher data rates within a given bandwidth.
Correct Answer
D. Higher data rates within a given bandwidth.Explanation
Adding more phase shifts allows for a higher number of distinct symbols to be transmitted, which in turn allows for a higher data rate within a given bandwidth. This is because each symbol represents a certain number of bits, and by increasing the number of symbols, more bits can be transmitted per unit of time. Therefore, the advantage of adding more phase shifts is higher data rates within a given bandwidth.Rate this question:
-
- 15.
(005) What is the first step in the pulse code modulation (PCM) process?
- A.
Discrete amplitudes are assigned to the sampling pulses.
- B.
A binary code number is assigned to the sample.
- C.
The quantizer limits the amplitude of the pulses.
- D.
The analog signal is band-limited.
Correct Answer
D. The analog signal is band-limited.Explanation
The first step in the pulse code modulation (PCM) process is to band-limit the analog signal.Rate this question:
-
- 16.
(005) What part of the pulse code modulation (PCM) process converts a continuous time signal into a discrete time signal?
- A.
Sampling.
- B.
Rectifying.
- C.
Oscillating.
- D.
Band limiting.
Correct Answer
A. Sampling.Explanation
The correct answer is Sampling. In pulse code modulation (PCM), the continuous time signal is converted into a discrete time signal through the process of sampling. Sampling involves taking periodic samples of the continuous signal at specific intervals, resulting in a series of discrete values that represent the original signal. This allows for the digital representation and transmission of the signal. Rectifying, oscillating, and band limiting are not directly involved in the conversion of continuous time to discrete time in PCM.Rate this question:
-
- 17.
(005) A type of pulse modulation (PM) that changes the amplitude of the pulse train to vary according to the amplitude of the input signal is called
- A.
Pulse width modulation (PWM).
- B.
Pulse position modulation.
- C.
Pulse duration modulation.
- D.
Pulse amplitude modulation.
Correct Answer
D. Pulse amplitude modulation.Explanation
Pulse amplitude modulation (PAM) is a type of pulse modulation where the amplitude of the pulse train is varied according to the amplitude of the input signal. This means that the height or intensity of the pulses in the pulse train is changed to represent the varying amplitude of the input signal. This allows for the transmission of analog signals over a digital communication system.Rate this question:
-
- 18.
(006) If an error should occur, what data transmission is lost in a synchronous transmission?
- A.
One character.
- B.
Block of data.
- C.
A parity bit.
- D.
Synchronization (SYNC) bit.
Correct Answer
B. Block of data.Explanation
In synchronous transmission, data is transmitted in blocks. Each block consists of multiple characters. If an error occurs during transmission, it means that one or more characters within the block have been corrupted or lost. Therefore, the correct answer is "Block of data" as the entire block of data is lost in case of an error in synchronous transmission.Rate this question:
-
- 19.
(007) When using vertical redundancy check (VRC), what significance does the amount of ones have in a data bit pattern?
- A.
Determines parity.
- B.
Determines transmission rate.
- C.
Determines whether transmission is in American Standard code for Information Interchange (ASCII) format.
- D.
Determines whether transmission is synchronous or asynchronous.
Correct Answer
A. Determines parity.Explanation
The amount of ones in a data bit pattern determines parity. Parity is a form of error checking where an extra bit is added to the data to ensure that the number of ones in the data is always even or odd. This allows the receiver to detect if there has been an error during transmission by checking the parity bit. If the number of ones in the received data does not match the expected parity, then an error has occurred.Rate this question:
-
- 20.
(007) What two error detection methods, when used together, are 98 perfent effective in detecting errors?
- A.
Checksum and cyclic redundancy check.
- B.
Longitudinal redundancy check and checksum.
- C.
Cyclic redundancy check and vertical redundancy check.
- D.
Vertical redundancy check and longitudinal redundancy check.
Correct Answer
D. Vertical redundancy check and longitudinal redundancy check. -
- 21.
(007) What error detection method adds stacked characters, divides it by 255, and disregards the answer except for the remainder?
- A.
Checksum.
- B.
Block check character.
- C.
Cyclic redundancy check.
- D.
Vertical redundancy check.
Correct Answer
A. Checksum.Explanation
Checksum is an error detection method that adds stacked characters, divides it by 255, and disregards the answer except for the remainder. It is commonly used in data transmission to detect errors that may occur during the transmission process. By comparing the calculated checksum at the receiving end with the transmitted checksum, any errors can be identified.Rate this question:
-
- 22.
(007) What error-correction technique sends a retransmittal request by the receiver to the sender if it finds an error in a received frame?
- A.
Error-correcting code.
- B.
Forward error control.
- C.
Redundant data transfer.
- D.
Automatic retransmit on request.
Correct Answer
D. Automatic retransmit on request.Explanation
Automatic retransmit on request is the error-correction technique that sends a retransmittal request by the receiver to the sender if it finds an error in a received frame. This technique allows the receiver to notify the sender about the error and request a retransmission of the frame to ensure accurate data transfer.Rate this question:
-
- 23.
(007) When using forward error control as a method of error correction, where does error correction take place?
- A.
Receiving end.
- B.
In the oscillator.
- C.
Transmitting end.
- D.
In the primary buffers.
Correct Answer
A. Receiving end.Explanation
When using forward error control as a method of error correction, error correction takes place at the receiving end. This means that the errors in the transmitted data are detected and corrected at the destination or receiver of the data. The receiver uses the error control mechanism to identify and fix any errors that may have occurred during transmission, ensuring that the received data is accurate and reliable.Rate this question:
-
- 24.
(008) What does an optical source do?
- A.
Terminates fober optics cable.
- B.
Converts electrical energy into optical energy.
- C.
Extend the distance and to preserve signal integrity.
- D.
Accepts optical signals and converts them into electrical signals.
Correct Answer
B. Converts electrical energy into optical energy.Explanation
An optical source is responsible for converting electrical energy into optical energy. This means that it takes electrical signals and transforms them into light signals that can be transmitted through optical fibers. This conversion is necessary in order to transmit data over long distances using fiber optic cables, as electrical signals cannot travel as far without significant loss of signal integrity. Therefore, an optical source plays a crucial role in enabling the transmission of data through fiber optic networks.Rate this question:
-
- 25.
(008) Light sources that are applicable to fiber optic waveguide are light-emitting diodes (LED) and
- A.
Photo transistors.
- B.
Hybrid photodiodes.
- C.
Semiconductor laser diodes.
- D.
Integrated photodiode/preamplifiers.
Correct Answer
C. Semiconductor laser diodes.Explanation
Semiconductor laser diodes are applicable to fiber optic waveguides because they emit a highly focused and coherent beam of light. This makes them ideal for transmitting signals over long distances through optical fibers. Light-emitting diodes (LEDs) are also used in fiber optic communication, but they have a broader beam and are typically used for shorter distances or in applications where cost is a consideration. Photo transistors, hybrid photodiodes, and integrated photodiode/preamplifiers are not light sources, but rather light detectors used to receive signals in fiber optic communication systems.Rate this question:
-
- 26.
(008) What type of light is emitted from a laser?
- A.
Incoherent.
- B.
Coherent.
- C.
Ordinary.
- D.
Invisible.
Correct Answer
B. Coherent.Explanation
A laser emits coherent light. Coherent light is light that has a fixed phase relationship between its waves, meaning that all the waves are in sync and have the same frequency and wavelength. This is different from incoherent light, which has waves that are not in sync and have different frequencies and wavelengths. Ordinary light refers to light from sources like the sun or a light bulb, which can be either coherent or incoherent. Invisible light refers to light that is not visible to the human eye, such as ultraviolet or infrared light.Rate this question:
-
- 27.
(008) Laser diode power coupling is measured in which range
- A.
Megawatt.
- B.
Microwatt.
- C.
Milliwatt.
- D.
Kilowatt.
Correct Answer
C. Milliwatt.Explanation
Laser diode power coupling is measured in the milliwatt range. This is because laser diodes are typically used in applications that require low to moderate power output. Milliwatts are a suitable unit for measuring the power output of laser diodes as they provide a precise measurement within the appropriate range for these devices. Megawatts, kilowatts, and microwatts are not commonly used to measure laser diode power coupling.Rate this question:
-
- 28.
(009) A device that accepts optical signals from an optical fiber and converts them into electrical signals is called an optical
- A.
Regenerator.
- B.
Transmitter.
- C.
Amplifier.
- D.
Receiver.
Correct Answer
D. Receiver.Explanation
An optical receiver is a device that accepts optical signals from an optical fiber and converts them into electrical signals. It is used in optical communication systems to receive and decode the transmitted information. The receiver plays a crucial role in the communication process by converting the optical signals back into electrical signals that can be processed and interpreted by electronic devices.Rate this question:
-
- 29.
(009) Small current that flows from a photodiode even with no light is called
- A.
Dark current.
- B.
Dispersion.
- C.
Distortion.
- D.
Ionization.
Correct Answer
A. Dark current.Explanation
Dark current refers to the small current that flows through a photodiode even in the absence of light. This current is caused by thermal excitation of charge carriers in the photodiode's semiconductor material. The dark current can affect the accuracy and sensitivity of the photodiode's measurements, as it adds to the signal that is generated when light is present. By understanding and compensating for the dark current, the performance of the photodiode can be optimized.Rate this question:
-
- 30.
(009) The responsivity of a photo detector is dependent on the
- A.
Emitter rise time.
- B.
Wavelength of light.
- C.
Signal-to-noise ratio (SNR).
- D.
Emitter modulation speed.
Correct Answer
B. Wavelength of light.Explanation
The responsivity of a photo detector refers to its ability to convert light energy into an electrical signal. This responsivity is dependent on the wavelength of the light being detected. Different photo detectors are designed to be sensitive to specific ranges of wavelengths, and their responsivity will vary accordingly. Therefore, the correct answer is "wavelength of light."Rate this question:
-
- 31.
(009) What are the two main types of photodetectors?
- A.
Positive intrinsic negative and avalanche photodiode.
- B.
Light-emitting diode (LED) and avalanche photodiode.
- C.
LED and semiconductor laser.
- D.
Tunnel and zener diodes.
Correct Answer
A. Positive intrinsic negative and avalanche photodiode.Explanation
The correct answer is "Positive intrinsic negative and avalanche photodiode." These are the two main types of photodetectors. A positive intrinsic negative (PIN) diode is a type of photodiode that operates based on the principle of the internal photoelectric effect, where incident light generates electron-hole pairs in the intrinsic region of the diode. An avalanche photodiode (APD) is a type of photodiode that operates based on the principle of avalanche multiplication, where electron-hole pairs are generated by incident light and then multiplied through impact ionization.Rate this question:
-
- 32.
(009) What photo detector converts one photon to one electron?
- A.
Light emitting diode (LED).
- B.
Avalanche photodiode.
- C.
Positive intrinsic negative (PIN) diode.
- D.
Integrated photodiode/preamplifier (IDP).
Correct Answer
C. Positive intrinsic negative (PIN) diode.Explanation
A positive intrinsic negative (PIN) diode is a type of photodetector that converts one photon to one electron. This is because the PIN diode has a wide depletion region, allowing it to absorb more photons and generate a larger current. This makes it more sensitive to low light levels and capable of converting individual photons into individual electrons.Rate this question:
-
- 33.
(010) What is used to extend the distance of a fiber optic communication systems link?
- A.
Receiver.
- B.
Transmitter.
- C.
Repeater.
- D.
Patch cords.
Correct Answer
C. Repeater.Explanation
A repeater is used to extend the distance of a fiber optic communication system's link. A repeater receives the optical signal, amplifies it, and then retransmits it to continue the signal transmission over longer distances. This helps to overcome the signal loss that occurs in fiber optic cables over long distances, ensuring that the signal remains strong and clear throughout the entire communication link.Rate this question:
-
- 34.
(010) Which repeater amplifies optical signal without converting to and from the electrical domain?
- A.
Repeaters.
- B.
Regenerators.
- C.
Optical amplifiers.
- D.
Receiver.
Correct Answer
C. Optical amplifiers.Explanation
Optical amplifiers are devices that amplify optical signals without converting them to electrical signals. They use a process called stimulated emission to amplify the signal by adding energy to it. This allows the signal to travel longer distances without degradation. Repeaters, on the other hand, regenerate electrical signals by converting them to optical signals and then back to electrical signals. Regenerators are similar to repeaters but are used for digital signals. Receivers are devices that receive and convert signals from one form to another, such as from optical to electrical.Rate this question:
-
- 35.
(011) Short sections of single fiber cables that has a connector at each end is called a
- A.
Pigtail.
- B.
Patch cord.
- C.
Jumper.
- D.
Breakout cables.
Correct Answer
B. Patch cord.Explanation
A short section of single fiber cables that has a connector at each end is called a patch cord. A patch cord is used to connect devices or components in a network or telecommunications system. It is often used to connect equipment in a data center or to connect a device to a patch panel. Patch cords are typically used for temporary or semi-permanent connections and can be easily plugged and unplugged. They are available in various lengths and connector types to accommodate different equipment and network configurations.Rate this question:
-
- 36.
(011) Which fiber-optic connector uses a quick-release, keyed bayonet couplings that are preferred in situations where severe vibrations are not expected?
- A.
Biconic.
- B.
Field connector (FC).
- C.
Straight tip (ST).
- D.
Sub-miniature, type A (SMA).
Correct Answer
C. Straight tip (ST).Explanation
The Straight tip (ST) fiber-optic connector uses quick-release, keyed bayonet couplings that are preferred in situations where severe vibrations are not expected. This type of connector provides a secure and reliable connection while allowing for easy installation and removal. The bayonet coupling ensures a tight and stable connection, making it suitable for applications where vibrations could potentially disrupt the connection.Rate this question:
-
- 37.
(011) Which fiber optic connector uses a push-pull engagement for mating?
- A.
Biconic.
- B.
Field connector (FC).
- C.
Subscriber (SC).
- D.
Sub-miniature, type A (SMA).
Correct Answer
C. Subscriber (SC).Explanation
The Subscriber (SC) fiber optic connector uses a push-pull engagement for mating. This means that the connector can be easily inserted and removed from the port by simply pushing and pulling it. This type of engagement is commonly used in SC connectors to ensure a secure and reliable connection between the fiber optic cables.Rate this question:
-
- 38.
(012) What initial nuclear radiation elements generate electromagnetic pulses?
- A.
Gamma rays and neutrons.
- B.
Thermally generated x-rays.
- C.
Transient radiation effects on electronics.
- D.
Neutrons and thermally generated X-rays.
Correct Answer
A. Gamma rays and neutrons.Explanation
Gamma rays and neutrons are the initial nuclear radiation elements that generate electromagnetic pulses. Gamma rays are high-energy photons that are emitted during nuclear reactions, while neutrons are neutral subatomic particles that are also released during nuclear reactions. Both gamma rays and neutrons have the ability to generate electromagnetic pulses, which can disrupt electronic devices and systems.Rate this question:
-
- 39.
(012) High-altitude electromagnetic pulse is what type of frequency phenomenon, and involces which frequency range?
- A.
Secondary; 1 hertz to 1 gigahertz.
- B.
Wideband; 1 hertz to 1 gigahertz.
- C.
Secondary; 10 hertz to 10 gigahertz.
- D.
Wideband; 10 hertz to 10 gigahertz.
Correct Answer
B. Wideband; 1 hertz to 1 gigahertz.Explanation
The correct answer is "Wideband; 1 hertz to 1 gigahertz." This means that high-altitude electromagnetic pulse is a wideband phenomenon that involves frequencies ranging from 1 hertz to 1 gigahertz.Rate this question:
-
- 40.
(012) A system-generated electromagnetic pulse is a problem for satellites and reentry vehicles that are
- A.
Susceptible to the wideband frequency phenomenon.
- B.
Directly exposed to nuclear radiations from a high-altitude burst.
- C.
Affected by the azimuthal magnetic fields and time-varying air conductivity.
- D.
Influenced by the signal fading or waveform distortion caused by the structured plasma field.
Correct Answer
B. Directly exposed to nuclear radiations from a high-altitude burst. -
- 41.
(012) Which distinct region of the source region electromagnetic pulse is produced by the interactions between the weapon products and the earth's atmosphere?
- A.
Secondary.
- B.
Radiated.
- C.
Plasma.
- D.
Source.
Correct Answer
D. Source.Explanation
The correct answer is "Source." In the context of the question, the source region refers to the area where the electromagnetic pulse is initially produced. This region is distinct from the other options provided (secondary, radiated, and plasma) which are not directly related to the interactions between the weapon products and the earth's atmosphere.Rate this question:
-
- 42.
(012) What electromagnetic pulse region is the principal threat to electronic systems by cable?
- A.
Local.
- B.
Source.
- C.
Radiated.
- D.
Long-line.
Correct Answer
C. Radiated.Explanation
The principal threat to electronic systems by cable is in the radiated electromagnetic pulse region. This means that the electromagnetic pulse is transmitted through the air and can induce currents and voltages in nearby cables, causing damage to electronic systems.Rate this question:
-
- 43.
(012) How does scintillation effect communications?
- A.
Large attenuation of the transmitted signal causing the received signal-to-noise (SNR) to fall below unity.
- B.
Transmitted signal fading caused by multiple path propagation through the structured plasma field.
- C.
Layers of charged electrons that are trapped and prevent transmissions through the layer.
- D.
Absorption of the transmitted signal through the contaminated area.
Correct Answer
B. Transmitted signal fading caused by multiple path propagation through the structured plasma field.Explanation
The scintillation effect on communications is caused by the fading of the transmitted signal due to multiple path propagation through the structured plasma field. This means that the signal is being affected by the variation in the plasma density along the transmission path, resulting in fluctuations in the received signal strength. This can lead to a decrease in the signal-to-noise ratio, making it difficult for the receiver to distinguish the signal from the background noise.Rate this question:
-
- 44.
(012) Atmospheric disturbances from initial nuclear radiation on higher frequencies affect comunications by which types of effects?
- A.
Blackout.
- B.
Absorption.
- C.
Scintillation.
- D.
Attenuation.
Correct Answer
C. Scintillation.Explanation
Atmospheric disturbances caused by initial nuclear radiation can affect communications through scintillation. Scintillation refers to the rapid fluctuations in the intensity and phase of electromagnetic waves as they pass through a turbulent medium, such as the atmosphere. These fluctuations can cause signal fading and distortion, leading to disruptions in communication. Absorption refers to the process of energy being absorbed by a medium, attenuation refers to the gradual decrease in signal strength over distance, and blackout refers to a complete loss of communication. However, in the context of the given question, scintillation is the most relevant effect caused by atmospheric disturbances from initial nuclear radiation.Rate this question:
-
- 45.
(013) Which one of the following statements are true converning shielding?
- A.
Cables should be of unshielded construction.
- B.
Only ventilation ports are shielded along the walls.
- C.
Sensitive equipment will be located within the shielded barrier.
- D.
All power lines supplying shielded areas does not require filters.
Correct Answer
C. Sensitive equipment will be located within the shielded barrier. -
- 46.
(013) What is the purpose of bonding?
- A.
To isolate facility from any external electrical electromagnetic propagation.
- B.
To reduce interference coupling around circuits and around interconnecting lines.
- C.
To ensure a mechanically strong, low impedance interconnection between metal objects.
- D.
To eliminate harmful differences of potential between the various telephone cables entering facility.
Correct Answer
C. To ensure a mechanically strong, low impedance interconnection between metal objects.Explanation
The purpose of bonding is to ensure a mechanically strong, low impedance interconnection between metal objects. This helps to create a reliable and efficient electrical pathway between the objects, reducing resistance and preventing the build-up of harmful differences in potential. By providing a secure bond, bonding also helps to minimize the risk of electrical shock and damage caused by electrical faults.Rate this question:
-
- 47.
(013) Which types of filters are always used in combination with surge arresters?
- A.
Linear.
- B.
Alternating current (AC) line.
- C.
Direct current (DC) DC line.
- D.
Power line.
Correct Answer
A. Linear.Explanation
Surge arresters are used to protect electrical systems from voltage surges or transients. Linear filters are often used in combination with surge arresters to further reduce and filter out any high-frequency noise or harmonics that may be present in the power system. This helps to ensure a clean and stable power supply to the connected equipment. Therefore, linear filters are always used in combination with surge arresters.Rate this question:
-
- 48.
(014) If the interference can be eliminated by disconnecting the receiving antenna, the source of the disturbance is most likely
- A.
Line noise.
- B.
Internal to the radio.
- C.
External to the radio.
- D.
Radio receiver trouble.
Correct Answer
C. External to the radio.Explanation
If disconnecting the receiving antenna eliminates the interference, it suggests that the source of the disturbance is external to the radio. This means that the interference is coming from an external source, such as other electronic devices or environmental factors, rather than being caused by internal issues within the radio itself.Rate this question:
-
- 49.
(014) What is an example of intentionally induced electromagnetic interference (EMI)?
- A.
Jamming.
- B.
Spurious responses.
- C.
Intermodulation.
- D.
Power line noise.
Correct Answer
A. Jamming.Explanation
Jamming is an example of intentionally induced electromagnetic interference (EMI). Jamming refers to the deliberate transmission of signals to disrupt or interfere with the operation of electronic devices or communication systems. It is often used in military operations to disrupt enemy communications or radar systems. Jamming can cause interference and disrupt the normal functioning of electronic equipment, causing a loss of signal or degraded performance. Spurious responses, intermodulation, and power line noise are examples of unintentional EMI, caused by factors such as faulty equipment, electromagnetic radiation from other sources, or electrical noise in power lines.Rate this question:
-
- 50.
(014) What type of electromagnetic interference (EMI) occurs when a receiver responds to off-frequency signals?
- A.
Rusty Bolt.
- B.
Co-channel.
- C.
Brute force.
- D.
Spurious responses.
Correct Answer
D. Spurious responses.Explanation
Spurious responses refer to electromagnetic interference that occurs when a receiver responds to off-frequency signals. This means that the receiver is picking up signals that are not on the intended frequency, leading to interference and potentially affecting the performance of the receiver.Rate this question:
-
Quiz Review Timeline +
Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.
-
Current Version
-
Mar 21, 2023Quiz Edited by
ProProfs Editorial Team -
Jul 19, 2011Quiz Created by
Ihatecdc
- 1W0510 Quizzes
- 2A251 Quizzes
- 2A552 Quizzes
- 2A651 Quizzes
- 2A652 Quizzes
- 2A654 Quizzes
- 2A656 Quizzes
- 2A671 Quizzes
- 2A6X1 Quizzes
- 2A753 Quizzes
- 2A852 Quizzes
- 2AX5X Quizzes
- 2AX7X Quizzes
- 2S051 Quizzes
- 2s071 Quizzes
- 2T251 Quizzes
- 3d052 Quizzes
- 3d054 Quizzes
- 3D151 Quizzes
- 3D152 Quizzes
- 3D153 Quizzes
- 3DX7X Quizzes
- 3e6x1 Quizzes
- 3P071 Quizzes
- 5j0x1 Quizzes
- Z3dx7x Quizzes
Back to top