This is the Multiples Choice Questions Part 1 of the Series in Wire and Wireless Communications System as one of the Communications Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies, Communications Books, Journals and other Communications References.
MCQ Topic Outline included in ECE Board Exam Syllabi
- MCQ in Mobile Communications
- MCQ in Cellular Communication
- MCQ in Trunk Radio
- MCQ in Radio Paging System
- MCQ in Facsimile
- MCQ in Telephone Set
- MCQ in Signaling
- MCQ in Transmission Considerations in long distance network
- MCQ in Insertion Loss
- MCQ in VF Repeaters
- MCQ in Traffic Calculations
- MCQ in Reference Equivalent and Standards
- MCQ in Telephone Networks
- MCQ in Billing
- MCQ in Network Hierarchy and Class type
- MCQ in Connection and Performance of Wire and Wireless Communications
Start Practice Exam Test Questions Part 1 of the Series
1. Typical speech power
A. 10 to 1000 µW
B. 100 to 1000 mW
C. 10 to 1000 nW
D. 100 to 1000 pW
Answer: Option A
Solution:
2. The maximum intelligibility for voice frequency is located between
A. 250 and 500 Hz
B. 1000 and 3000 Hz
C. 500 and 1000 Hz
D. 3000 and 5000 Hz
Answer: Option B
Solution:
3. The maximum voice energy is located between
A. 250 and 500 Hz
B. 1000 and 3000 Hz
C. 500 and 1000 Hz
D. 3000 and 5000 Hz
Answer: Option A
Solution:
4. A device used to measure speech volume.
A. speech meter
B. volume meter
C. volume unit meter
D. speedometer
Answer: Option C
Solution:
5. By definition, for a sine wave
A. 0 dBm = 0 V.U.
B. 0 dBW = 0 V.U.
C. 0 dBa = 0 V.U.
D. 0 dBf = 0 V.U.
Answer: Option A
Solution:
6. Presently, this is the “standard” frequency bandwidth for voice transmission.
A. 0 to 4000 Hz
B. 100 to 3400 Hz
C. 300 to 3400 Hz
D. 300 to 3000 Hz
Answer: Option C
Solution:
7. Which of the following is commonly used wire for subscriber loop design?
A. AWG # 19
B. AWG # 18
C. AWG # 30
D. AWG # 33
Answer: Option A
Solution:
8. The resistance limit for No. 2 Crossbar Exchange (US) is
A. 2000 Ω
B. 1300 Ω
C. 1250 Ω
D. 1200 Ω
Answer: Option B
Solution:
9. AWG # 26 has a typical loss of
A. 0.21 dB/1000 ft.
B. 0.32 dB/1000 ft.
C. 0.41 dB/1000 ft.
D. 0.51 dB/1000 ft.
Answer: Option D
Solution:
10. What is the standard voice channel spacing?
A. 44 MHz
B. 40 kHz
C. 4 kHz
D. 40 MHz
Answer: Option C
Solution:
11. Which tester is used to measure SWR?
A. Multimeter
B. Oscilloscope
C. Spectrum analyzer
D. Reflectometer
Answer: Option D
Solution:
12. What is singing?
A. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency equal to the sum of the frequencies of the signals intermodulated.
B. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency higher than that of the signal having the highest frequency.
C. An undesired self-sustained oscillation in a system, generally caused by excessive positive feedback.
D. An art or form of entertainment that can make one rich.
Answer: Option C
Solution:
13. Which stage increases the selectivity of the circuit in an AM receiver?
A. Detector
B. IF stage
C. Modulator
D. Mixer
Answer: Option B
Solution:
14. The ________ of radio receiver amplify weak signal and produce a desirable intelligence at the output speaker.
A. sensitivity
B. selectivity
C. reliability
D. fidelity
Answer: Option A
Solution:
15. Full-duplex transmission means
A. One-way transmission
B. 24-hour transmission
C. Broadcast transmission
D. Two-way simultaneous transmission
Answer: Option D
Solution:
16. What is a multidrop line?
A. A piece of wire with a thick insulating material that serves to protect the conductive materials from damage in the event the wire is dropped.
B. A line designed to withstand high pressure.
C. A line or circuit interconnecting several situations.
D. A bus line
Answer: Option C
Solution:
17. A passive _________ is an electronic device which reduces signal strength by a specified amount in dB.
A. Splitter
B. Filter
C. Trimmer
D. Attenuator
Answer: Option D
Solution:
18. The signal quality of the calls is constantly monitored by the base station, when the quality of the calls drops below a certain specified level. The base request the MTSO to try and find a better cell site.
A. Hand-off
B. Cell splitting
C. Roaming
D. Frequency reuse
Answer: Option C
Solution:
19. A digital identification associated with a cellular system.
A. SAT
B. SID
C. ESN
D. MIN
Answer: Option D
Solution:
20. How many seconds does facsimile transmit a stranded page?
A. 5
B. 10
C. 20
D. 25
Answer: Option D
Solution:
21. A kind of recording used in facsimile.
A. Electrolytic recording
B. Electrothermal recording
C. Electropercussive recording
D. Electrostatic recording
Answer: Option A
Solution:
22. A type of distortion a facsimile produce when it becomes out of synchronization?
A. Pincushion
B. Barrel
C. Skewing
D. Fattening
Answer: Option C
Solution:
23. What is an acoustic coupler?
A. A device that radiates audible signals via a transmitting antenna
B. A device that converts electric signals into audio signals, enabling data to be transmitted over the public telephone network via a conventional telephone handset
C. A device that receives audible signals and retransmits them at VHF frequencies
D. A transducer
Answer: Option B
Solution:
24. Cause a herringbone pattern in facsimile
A. Single-frequency interference
B. Crosstalk
C. Phase jitter
D. Noise
Answer: Option B
Solution:
25. The _______ in an FM receiver causes a stronger signal to dominate over a weaker signal on the same frequency.
A. Capture effect
B. Flywheel effect
C. Hall effect
D. Skin effect
Answer: Option A
Solution:
26. A device that converts a 2-wire circuit to a 4-wire circuit.
A. RS-232 interface
B. Hybrid circuit
C. Balun
D. Stub
Answer: Option B
Solution:
27. ______ theory is deciding between a set of hypothesis when given a collection of imperfect measurements.
A. Estimation
B. Traffic
C. Decision
D. Nyquist
Answer: Option C
Solution:
28. ______ of a data reduction says that when reducing a set of data into the form of an underlying mode, one should be maximally non-committal with respect to missing data.
A. Jaynes maximum entropy principle
B. Kullback principle of minimum discrimination
C. Minimum discrimination
D. Maximum entropy
Answer: Option A
Solution:
29. _______ is selecting the best value of a parameter from a continuum of possible values when gives a collection if imperfect measurements
A. Estimation
B. Traffic
C. Decision
D. Nyquist
Answer: Option A
Solution:
30. Combination of madulator, channel, and detector.
A. Transceiver
B. Transponder
C. T/R channel
D. Discrete channel
Answer: Option D
Solution:
31. What is the frequency band of DECT?
A. 1.28 – 1.30 GHz
B. 1.68 – 1.70 GHz
C. 1.48 – 1.50 GHz
D. 1.88 – 1.90 GHz
Answer: Option D
Solution:
32. How many simultaneous calls does each DECT system can support?
A. 96
B. 12
C. 24
D. 49
Answer: Option B
Solution:
33. How many simultaneous calls does a DECT radio transceiver can assess at any given time?
A. 120
B. 240
C. 480
D. 960
Answer: Option A
Solution:
34. The AGC voltage of a radio receiver is always _______.
A. Present before adjustments can be made
B. DC, but may have either polarity positive DC
C. Positive DC
D. Negative
Answer: Option B
Solution:
35. What is a concentrator?
A. A system that improves the signal-to-noise ratio by compressing the volume range of a signal.
B. A device that varies the characteristics of a carrier signal in accordance with the waveform of a modulating signal which contains useful information
C. A switching system that lets a large number of telephone or data processing subscribers use a lesser number of transmission lines or a narrow bandwidth
D. Equipment in the central office.
Answer: Option C
Solution:
36. If you find that an SAW filter output is 6 dB down from the input of a receiver during test, ______
A. This is normal.
B. The device if faulty
C. The receiver is improperly terminated
D. The filter is not resonating
Answer: Option A
Solution:
37. A triple conversion superheterodyne receiver, diode mixer stages are
A. Operated in the linear region
B. Operated in the nonlinear region
C. Operated as Class-A amplifiers
D. Operated as Class-B amplifiers
Answer: Option B
Solution:
38. What is a leased line?
A. A piece of wire used in a local area network in one building
B. A piece of wire connecting a telephone set to a PABX
C. A temporary connection of one computer to a mainframe via a modern and a telephone line
D. A permanent circuit for a private use within a communication network
Answer: Option D
Solution:
39. If two FM signals of different strengths are received on the same frequency
A. One steady heterodyne will appear in the AM output
B. Both will appear in the AF output
C. Only the stronger will appear in the AF output
D. Neither signal will be intelligence unless the weaker signal is at least 10 times
Answer: Option C
Solution:
40. Cellular mobile system was first operated in
A. 1979
B. 1981
C. 1983
D. 1985
Answer: Option C
Solution:
41. TACS is a cellular system with ______ channels.
A. 666
B. 1000
C. 832
D. 200
Answer: Option B
Solution:
42. Supervisory Audio Tone (SAT) has _______ frequency.
A. 5960 Hz
B. 6000 Hz
C. 6040 Hz
D. 1004 z
Answer: Option B
Solution:
43. What is the number of channels of a cellular system with an allocated spectrum of 25 MHz and with a channel of 30 kHz bandwidth?
A. 833
B. 240
C. 1000
D. 666
Answer: Option A
Solution:
44. GSM uses what digital modulation technique?
A. QAM
B. GFSK
C. BPSK
D. GMSK
Answer: Option B
Solution:
45. What is the power output of Personal Communication System (PCS)?
A. 10 mW
B. 75 mW
C. 150 mW
D. 10 W
Answer: Option A
Solution:
46. RG-B8 cable has a loss of about ______ dB at cellular frequencies up to 15 ft. length.
A. 2
B. 1
C. 4
D. 3
Answer: Option D
Solution:
47. The signals designed to keep the receivers and transmitters aligned.
A. Carrier frequencies
B. Pilot carrier signals
C. Synchronizing signals
D. Reference signals
Answer: Option B
Solution:
48. If the spacing of a two-wire open air transmission line is 12 inches and the conductor diameter is 0.25 inch, the characteristic impedance is
A. 547 Ω
B. 357 Ω
C. 273 Ω
D. 300 Ω
Answer: Option A
Solution:
49. The impedance of the quarterwave transformer used to match a 600 Ω line to a 300 Ω load is
A. 382 Ω
B. 424 Ω
C. 565 Ω
D. 712 Ω
Answer: Option B
Solution:
50. When a line and a load are match the reflection coefficient is
A. Unity
B. Zero
C. Positive infinity
D. Negative infinity
Answer: Option B
Solution:
Questions and Answers in Wire and Wireless Communications System Series
Following is the list of multiple choice questions in this brand new series:
Complete List of MCQ in Communications Engineering per topic
P inoyBIX educates thousands of reviewers and students a day in preparation for their board examinations. Also provides professionals with materials for their lectures and practice exams. Help me go forward with the same spirit.
“Will you subscribe today via YOUTUBE?”
