(Last Updated On: February 9, 2020)
This is the Self-test in Chapter 14: Modern Communications Applications from the book COMMUNICATIONS ELECTRONICS by Louis E. Frenzel. If you are looking for a reviewer in Communications Engineering this will definitely help. I can assure you that this will be a great help in reviewing the book in preparation for your Board Exam. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.
Start Practice Exam Test Questions
Direction: Either Supply the missing word(s) in each statement or Choose the letter that best answers each question.
1. Images are converted into electrical signals by a process of _____ with a light source and photosensitive detector.
2. The most common transmission medium for fax signals is _____.
3. Standards for fax transmission are set by the _____.
4. The modulation method used in group 1 machines was PM with black = _____ Hz and white= _____ Hz.
5. Vestigial sideband AM is used in group _____ machines.
6. The photosensitive device used in most modern fax machines to convert a scanned line into an analog signal is a(n)
7. Most modem fax machines are of the group _____ type.
8. To ensure compatibility between sending and receiving fax machines, control logic carries out the process of _____ by audio tones prior to transmission.
9. The most commonly used type of printer in a fax machine is a(n) _____ printer.
10. The upper speed limit of a G3 fax machine over telephone lines is _____ baud.
11. The resolution of a G3 fax machine is typically _____ lines per-inch.
12. The two modulation techniques used in G3 machines are _____.
13. A fax transmission is usually _____ (full, halt) duplex.
14. The speed and resolution of group 4 fax transmissions are _____ kbits/s and _____ lines per inch.
15. True or false. Fax can transmit photos and drawings as well as printed text.
16. True or false. Fax signals may not be transmitted by radio.
17. True or false. Group 4 transmission do not use the standard telephone lines.
18. The area to be served by a cellular telephone system is divided into adjacent _____.
19. The master control station for a group of cells is called the _____.
20. Name two reasons why there are more channels, available in cellular systems than in older mobile telephone systems.
21. The number of channels available is _____.
22. True or false. Cellular telephone radios operate full duplex.
23. The type of modulation used in a cellular radio is _____.
24. The maximum power output of a cellular transmitter is _____ W.
25. The transmit frequency range is _____ to _____ MHz.
26. The receive frequency range is _____ to _____ MHz.
27. Channels pacing is _____ kHz.
28. Separation between send and receive frequencies is _____ MHz.
29. Transmit and receive frequencies are determined by a(n) _____.
30. Common first IFs are _____ and _____ MHz. Common second IFs are _____ and _____ MHz.
31. The APC circuit causes the transmitter power to _____ based on an input control signal from the MTSO.
32. A _____ allows the transmitter and receiver to share an antenna.
33. True or false. The transmit and receive channel is selected by the operator. .
34. The source of the frequency divider ratios in the frequency synthesizer PLLs is the _____.
35. Name two signals that are transmitted back to the cell site and are monitored by the MTSO.
36. Name three conditions in the transceiver that are controlled by the MTSO.
37. A dc signal derived from the demodulator and used to tell the MTSO about received signal strength is called the _____.
38. A receiver has a first IF of 82.2 MHz. The second IF is 456 kHz. The LO frequency on the second mixer is _____ MHz.
39. The section of the cellular transceiver that interprets the serial digital data from the cell site and MTSO is the _____ unit.
40. How many microprocessors do most cellular transceivers contain?
41. The handset is part of the _____ section of the transceiver.
42. When the speed of radio signals is known, radar can be used to determine the _____ of a target.
43. An echo is the _____ from a target.
44. The directivity of the radar antenna determines the _____ of a target.
45. The speed of a radar signal is _____ s/nmi.
46. The elapsed time between radiating a radar signal and receiving its echo is 43.2 s. The target distance in nautical miles is _____.
47. If a target is 1000 yd away, the time period between the transmission of the signal and receipt of the echo is _____ s.
48. One nautical mile is equal to _____ statute miles.
49. For optimum reflection from a target, the wavelength of the radar signal should be _____ compared to the size of the target.
50. Radars operate in the _____ frequency range.
51. True or false. Both the transmitter and receiver in a radar share the same antenna.
52. The two main types of radar are _____.
53. A frequency shift of sound, radio, or light waves that occurs as the result of the relative motion between objects is called the _____ effect.
54. A CW radar operates at a frequency of 14 GHz. A frequency shift of 25 kHz is produced by a moving target. Its speed is _____ mi/h.
55. True or false. Distance can be measured with constant-frequency CW radar.
56. A waveguide assembly that lets the transmitter and receiver share an antenna is called a(n) _____.
57. The most commonly used component in a radar transmitter is a(n) _____ tube.
58. Both TR and ATR tubes incorporate a(n) _____.
59. The output display in a radar is usually a(n) _____.
60. A display that sweeps outward from the center of the screen while rotating is known as a(n) _____.
61. A radar using multiple antennas to shape the beam width and automatically adjust directivity is known as a(n) _____ radar.
62. The bandwidth of a standard TV signal is _____ MHz.
63. The video carrier is _____ modulated and the sound carrier is _____ modulated.
64. The spacing between the sound and picture carriers is _____ MHz.
65. TV stations operate in the _____ and _____ regions of the spectrum.
66. The brightness signal produced by a video camera is called the _____ or _____ signal.
67. Two electronic imaging devices used in TV cameras to produce video signals are the _____ and the _____.
68. The process that breaks up a picture or scene into serially transmitted signals is called _____.
69. The three basic colors of light which can be used to produce any other color are _____ , _____, and _____.
70. A NTSC TV picture or one frame of video is composed of _____ scan lines.
71. A field consists of _____ scan lines.
72. The field and frame rates are _____ and _____ Hz respectively.
73. The time needed to scan one horizontal line in a color TV set is _____.
74. To keep the picture at the receiver in step with the transmitted signal, _____ are added to the video.
75. The circuit that lets the picture and sound transmitters use the same antenna is the _____.
76. The color in a scene is generated by a camera that develops three signals that represent the amount of _____, _____, and _____ light present along every scan line.
77. The red, greed, and blue color signals are combined in a resistive matrix to produce the two color signals called _____ and _____.
78. The two color signals are fed to _____ circuits that produce _____ modulation.
79. The color signals modulate a subcarrier with a frequency of _____.
80. The characteristic of the composite color signal that tells the receiver the transmitted color is its _____.
81. The _____ signal can be formed by adding the color signals in the following proportion: 0.11B +0.59G + O.3R.
82. Channel selection in the tuner is accomplished by using a(n) _____ for a local oscillator.
83. The _____ portion of a modern TV set uses digitally coded infrared signals for channel, volume, and other changes.
84. A channel 33 UHF TV station has a picture carrier frequency of 585.25 MHz. The sound carrier frequency is _____.
85. The frequency of the video signal representing fine detail along a scan line can have a frequency up to about _____.
86. The TV receiver sound IF is _____ MHz, and the picture IF is _____ MHz.
87. The name of the special filter that provides most of the adjacent channel selectivity for the TV receiver is _____.
88. Spectrum space is conserved by using _____ modulation for the video in a TV signal.
89. In the TV receiver, the picture and sound IF beat together to form the sound IF of _____ MHz.
90. Two common sound demodulators in TV receivers are the _____ and the _____.
91. The composite color signal is demodulated in two _____ demodulator circuits fed with quadrature 3.58-MHz signals from a subcarrier oscillator.
92. The. 3.58-MHz subcarrier oscillator in the receiver is phase- and frequency-synchronized to the _____ signal transmitted along with the horizontal sync pulses.
93. The _____ circuit strips the horizontal sync pulses from the video detector output.
94. The horizontal sync pulses synchronize in internal sweep oscillator to a frequency of _____ Hz.
95. The vertical sweep oscillator is synchronized to a frequency of _____ Hz by as sync pulse derived by _____ the horizontal sync pulses occurring during the vertical blanking interval.
96. The horizontal and vertical sweep signals are currents with the shape of a(n) _____.
97. The sweep signals are applied to the _____ assembly around the neck of the picture tube.
98. The electron beam is generated by the _____ element in the picture tube and focused into a narrow beam by the
99. The electron beam is deflected and swept across the face of the picture tube by _____ generated by the _____.
100. A color CRT contains _____ electron guns to excite the color dot triads on the face of the tube.
101. The _____ circuits ensure that the electron beams strike the correct color dots.
102. The _____ stage is used as switching power supply to develop the HV required to operate the picture tube.
103. The transformer used to step up and step down the horizontal sync pulses is called the _____.
104. The name given to the cable TV station that collects and distributes the cable signals is _____.
105. The, main cables used to distribute the TV signals to subscribers are called the _____ and _____.
106. The coaxial cables that feed individual houses are called _____ and typically have a characteristic impedance of _____ ohms.
107. The cable TV station may change the TV signal frequency by translating it to another frequency by using a _____.
108. Cable attenuation occurring during distribution is overcome by using _____.
109. The cable box used by the subscriber contains two, main circuits, the _____ and the _____.
110. The output of the cable box is a TV signal on channel _____ or _____ that is connected to the _____ of the TV set.
111. Four advantages of cable TV are _____, _____, _____, and _____.