TEST BANK
Test Bank for Electronic Communications- A Systems
Approach
1st Edition
KA
G
U
A
,Jeffrey Beasley: Electronic Communications-A Systems Approach
(All Answers are in Bold)
Chapter 1: Fundamental Communications Concept
Multiple Choice Questions
1. What agency in the United States has been given the authority to establish and enforce
regulations regarding the use of radio transmitters and other generators of radio-
frequency energy?
A. Transport and Communications Ministry
B. Federal Communications Commission (FCC)
C. International Telecommunication Union (ITU)
D. Bell Laboratories
KA
2. What three ratios do decibels represent?
A. Powers, voltages, currents
B. Powers, voltages, frequencies
C. Voltages, frequencies, impedances
G
D. Logarithms, voltages, currents
3. Electric and magnetic fields both result from voltage potentials and .
U
A. Radio frequencies
B. Audio frequencies
A
C. Current flows
D. Electric charges
4. The carrier is often a(n) .
A. sine wave
B. vector
C. angular frequency
D. amplitude modulation
5. Electronics as a discipline within the field of physical science emerged from the
discovery of .
A. microwaves
B. gamma rays
C. cosmic rays
D. radio waves
,6. What two factors limit all communication systems?
A. Bandwidth and noise
B. Bandwidth and frequency
C. Noise and decibels
D. Noise and currents
7. You are troubleshooting a piece of equipment and you find that unauthorized
modifications may have been performed on the equipment. What type of failure does this
situation represent?
A. Faulty
B. Complete
C. Induced
D. Poor system performance
8. Which of the following is an essential attribute for being an effective troubleshooter?
KA
A. To know the latest trends in noise analysis
B. To be able to limit the frequency response
C. To know the conversion from the time to the frequency domain
D. To be able to isolate faulty components quickly and repair the defective circuit
9. Which of the following is the most troublesome form of external noise?
G
A. Atmospheric
B. Human-made
U
C. Space
D. Thermal
A
10. White noise is directly proportional to both temperature and .
A. bandwidth
B. AC voltage
C. power transfer
D. frequency
11. The overall noise-intensity versus frequency curves for semiconductor devices would
have what type of shape?
A. Angular
B. Square
C. Bathtub
D. Uneven
12. Which of the following did French mathematician Jean Baptiste Joseph Fourier develop?
, A. A means to break down any periodic waveform into a series of sine and/or cosine
waves at multiples of the fundamental frequency.
B. He created thermal interactions between free electrons and vibrating ions in a
conductor.
C. The formula for calculating shot noise contributed for a complete transistor.
D. The relative measure of the desired signal power to the noise power.
13. Which of the following pieces of equipment would be considered advanced test
equipment?
A. Digital multimeter (DMM)
B. Broadband oscilloscope
C. Spectrum analyzer
D. RF generator
14. When troubleshooting, why would you perform voltage and resistance checks?
A. To check for signals
KA
B. To eliminate induced failures
C. To observe frequency spectra
D. To isolate defective components
15. Why would you use Friiss’s formula?
G
A. To provide the overall noise effect of a multistage system.
B. To break down any periodic waveform into a series of sine and/or cosine waves at
multiples of the fundamental frequency.
U
C. To establish that different users can share bands of frequencies provided that each
user was assigned exclusive use of a frequency range within that band.
D. To show how the construction of a square wave can be seen to be made up of a
A
number of sinusoids.
16. What does the graphical display produced by an oscilloscope represent?
A. Signals in the frequency domain
B. Time-domain representation
C. Amplitude of each frequency component
D. Amplitude characteristics
17. consists of a mixture of signals at all frequencies and at randomly
occurring amplitudes.
A. Decibel units
B. Frequency
C. Bandwidth
D. Noise
,18. What do modulated signals convey?
A. Information
B. Voltage
C. Noise
D. Power
19. Which of the following could cause a complete failure in a piece of equipment?
A. Sporadic circuit operation
B. Open power resistors
C. Poor soldering
D. Poor alignment
20. If you were troubleshooting a piece of equipment and you heard a frying noise, what
would this indicate?
KA
A. A wire is loose
B. The power is weakening
C. A component is about to fail
D. The equipment has been abused
G
21. What does the noise figure (NF) specify?
A. Exactly how noisy a device is
U
B. The noise content at a specific point
C. The paths in which the charge carriers move
A. The ultimate noise performance
A
22. The terms Johnson, thermal, and noise may be used interchangeably.
A. white
B. space
C. internal
D. external
23. Which of the following defines frequency domain?
A. Square waves are made up of the fundamental and its odd -numbered harmonics
B. Amplitude is viewed as a function of frequency rather than of time
C. Amplitude of each harmonic decreases as the frequency increases
D.Any or all of the sine or cosine terms may be zero, and there are no restrictions on
their amplitudes
, 24. Why are bandwidths valuable?
A. Waveforms are limited.
B. Analog signals are digitized.
C. Wireless channels are impractical.
D. Frequencies are scarce.
25. What is the function of a transducer?
A. Displays waveforms in the time domain
B. Converts energy from one form to another
C. Allows for spectrum analysis to be accomplished relatively easily in software
D. Supplies test signal at the input of a circuit
KA
G
U
A
Test Bank for Electronic Communications- A Systems
Approach
1st Edition
KA
G
U
A
,Jeffrey Beasley: Electronic Communications-A Systems Approach
(All Answers are in Bold)
Chapter 1: Fundamental Communications Concept
Multiple Choice Questions
1. What agency in the United States has been given the authority to establish and enforce
regulations regarding the use of radio transmitters and other generators of radio-
frequency energy?
A. Transport and Communications Ministry
B. Federal Communications Commission (FCC)
C. International Telecommunication Union (ITU)
D. Bell Laboratories
KA
2. What three ratios do decibels represent?
A. Powers, voltages, currents
B. Powers, voltages, frequencies
C. Voltages, frequencies, impedances
G
D. Logarithms, voltages, currents
3. Electric and magnetic fields both result from voltage potentials and .
U
A. Radio frequencies
B. Audio frequencies
A
C. Current flows
D. Electric charges
4. The carrier is often a(n) .
A. sine wave
B. vector
C. angular frequency
D. amplitude modulation
5. Electronics as a discipline within the field of physical science emerged from the
discovery of .
A. microwaves
B. gamma rays
C. cosmic rays
D. radio waves
,6. What two factors limit all communication systems?
A. Bandwidth and noise
B. Bandwidth and frequency
C. Noise and decibels
D. Noise and currents
7. You are troubleshooting a piece of equipment and you find that unauthorized
modifications may have been performed on the equipment. What type of failure does this
situation represent?
A. Faulty
B. Complete
C. Induced
D. Poor system performance
8. Which of the following is an essential attribute for being an effective troubleshooter?
KA
A. To know the latest trends in noise analysis
B. To be able to limit the frequency response
C. To know the conversion from the time to the frequency domain
D. To be able to isolate faulty components quickly and repair the defective circuit
9. Which of the following is the most troublesome form of external noise?
G
A. Atmospheric
B. Human-made
U
C. Space
D. Thermal
A
10. White noise is directly proportional to both temperature and .
A. bandwidth
B. AC voltage
C. power transfer
D. frequency
11. The overall noise-intensity versus frequency curves for semiconductor devices would
have what type of shape?
A. Angular
B. Square
C. Bathtub
D. Uneven
12. Which of the following did French mathematician Jean Baptiste Joseph Fourier develop?
, A. A means to break down any periodic waveform into a series of sine and/or cosine
waves at multiples of the fundamental frequency.
B. He created thermal interactions between free electrons and vibrating ions in a
conductor.
C. The formula for calculating shot noise contributed for a complete transistor.
D. The relative measure of the desired signal power to the noise power.
13. Which of the following pieces of equipment would be considered advanced test
equipment?
A. Digital multimeter (DMM)
B. Broadband oscilloscope
C. Spectrum analyzer
D. RF generator
14. When troubleshooting, why would you perform voltage and resistance checks?
A. To check for signals
KA
B. To eliminate induced failures
C. To observe frequency spectra
D. To isolate defective components
15. Why would you use Friiss’s formula?
G
A. To provide the overall noise effect of a multistage system.
B. To break down any periodic waveform into a series of sine and/or cosine waves at
multiples of the fundamental frequency.
U
C. To establish that different users can share bands of frequencies provided that each
user was assigned exclusive use of a frequency range within that band.
D. To show how the construction of a square wave can be seen to be made up of a
A
number of sinusoids.
16. What does the graphical display produced by an oscilloscope represent?
A. Signals in the frequency domain
B. Time-domain representation
C. Amplitude of each frequency component
D. Amplitude characteristics
17. consists of a mixture of signals at all frequencies and at randomly
occurring amplitudes.
A. Decibel units
B. Frequency
C. Bandwidth
D. Noise
,18. What do modulated signals convey?
A. Information
B. Voltage
C. Noise
D. Power
19. Which of the following could cause a complete failure in a piece of equipment?
A. Sporadic circuit operation
B. Open power resistors
C. Poor soldering
D. Poor alignment
20. If you were troubleshooting a piece of equipment and you heard a frying noise, what
would this indicate?
KA
A. A wire is loose
B. The power is weakening
C. A component is about to fail
D. The equipment has been abused
G
21. What does the noise figure (NF) specify?
A. Exactly how noisy a device is
U
B. The noise content at a specific point
C. The paths in which the charge carriers move
A. The ultimate noise performance
A
22. The terms Johnson, thermal, and noise may be used interchangeably.
A. white
B. space
C. internal
D. external
23. Which of the following defines frequency domain?
A. Square waves are made up of the fundamental and its odd -numbered harmonics
B. Amplitude is viewed as a function of frequency rather than of time
C. Amplitude of each harmonic decreases as the frequency increases
D.Any or all of the sine or cosine terms may be zero, and there are no restrictions on
their amplitudes
, 24. Why are bandwidths valuable?
A. Waveforms are limited.
B. Analog signals are digitized.
C. Wireless channels are impractical.
D. Frequencies are scarce.
25. What is the function of a transducer?
A. Displays waveforms in the time domain
B. Converts energy from one form to another
C. Allows for spectrum analysis to be accomplished relatively easily in software
D. Supplies test signal at the input of a circuit
KA
G
U
A
