3D1X3 CDC Volume 1 Ure

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Ihatecdc

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Quizzes Created: 3 | Total Attempts: 4,675

Questions: 100 | Attempts: 2,064 | Updated: Mar 21, 2023

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Read the damn title also jones.

Questions and Answers

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 radiation

Explanation
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.

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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.

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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.

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0
1
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.

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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 kHz

Explanation
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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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."

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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, 2023

Quiz Edited by
ProProfs Editorial Team
Jul 19, 2011

Quiz Created by
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3D1X3 CDC Volume 1 Ure

(001) What reason for modulation involves modulating low frequency signals for transmission over long distances?

(001) What are the three general categories used to produce modulation in radio frequency (RF) transmission today?

(002) When the modulating signal and carrier signal are combined within a modulator, the output signal contains a/an

(002) If a carrier frequency of 1 MHz and a modulating tone of 10 kHz goes to the modulator, the output signal includes

(002) If the modulating audio signal is 10kHz wide, what is the bandwidth of the transmitted amplitude modulated signal?

(002) The bandwidth of an amplitude modulated signal is

(002) The amount of effect or change that the intelligence has on the carrier in an amplitude modulated signal is expressed as the

(002) Which statement concerning bandwidth is true?

(002) Reducing modulation to less than 100 percent gives

(003) In frequency modulation (FM), the amount of oscillator frequency change is

(003) In frequency modulation (FM), what is considered a significant sideband?

(003) What is the formula to find the modulating index?

(004) In phase modulation (PM), the carrier's

(004) What is the advantage of adding more phase shifts?

(005) What is the first step in the pulse code modulation (PCM) process?

(005) What part of the pulse code modulation (PCM) process converts a continuous time signal into a discrete time signal?

(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

(006) If an error should occur, what data transmission is lost in a synchronous transmission?

(007) When using vertical redundancy check (VRC), what significance does the amount of ones have in a data bit pattern?

(007) What two error detection methods, when used together, are 98 perfent effective in detecting errors?

(007) What error detection method adds stacked characters, divides it by 255, and disregards the answer except for the remainder?

(007) What error-correction technique sends a retransmittal request by the receiver to the sender if it finds an error in a received frame?

(007) When using forward error control as a method of error correction, where does error correction take place?

(008) What does an optical source do?

(008) Light sources that are applicable to fiber optic waveguide are light-emitting diodes (LED) and

(008) What type of light is emitted from a laser?

(008) Laser diode power coupling is measured in which range

(009) A device that accepts optical signals from an optical fiber and converts them into electrical signals is called an optical

(009) Small current that flows from a photodiode even with no light is called

(009) The responsivity of a photo detector is dependent on the

(009) What are the two main types of photodetectors?

(009) What photo detector converts one photon to one electron?

(010) What is used to extend the distance of a fiber optic communication systems link?

(010) Which repeater amplifies optical signal without converting to and from the electrical domain?

(011) Short sections of single fiber cables that has a connector at each end is called a

(011) Which fiber-optic connector uses a quick-release, keyed bayonet couplings that are preferred in situations where severe vibrations are not expected?

(011) Which fiber optic connector uses a push-pull engagement for mating?

(012) What initial nuclear radiation elements generate electromagnetic pulses?

(012) High-altitude electromagnetic pulse is what type of frequency phenomenon, and involces which frequency range?

(012) A system-generated electromagnetic pulse is a problem for satellites and reentry vehicles that are

(012) Which distinct region of the source region electromagnetic pulse is produced by the interactions between the weapon products and the earth's atmosphere?

(012) What electromagnetic pulse region is the principal threat to electronic systems by cable?

(012) How does scintillation effect communications?

(012) Atmospheric disturbances from initial nuclear radiation on higher frequencies affect comunications by which types of effects?

(013) Which one of the following statements are true converning shielding?

(013) What is the purpose of bonding?

(013) Which types of filters are always used in combination with surge arresters?

(014) If the interference can be eliminated by disconnecting the receiving antenna, the source of the disturbance is most likely

(014) What is an example of intentionally induced electromagnetic interference (EMI)?

(014) What type of electromagnetic interference (EMI) occurs when a receiver responds to off-frequency signals?