Communications Engineering Coaching Materials: Section 5 Module 18

This is the Section 5 Module 18 of the compiled Communications Coaching Materials taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies (EST), Communications Books, Journals and other Communications References. This particular Coaching Notes in Communications Engineering has random Questions and Answers in random topics. Make sure to familiarize each questions to increase the chance of passing the ECE Board Exam.

Communications Engineering Coaching: Section 5 Module 18

QUESTIONS	ANSWERS
1. The frame alignment format for DS-1 signal contains	1 bit
2. The line coding scheme used for DS-1 signal is	Bipolar
3. Circuit that prevents dial pulsing from ringing the bell	Anti-tinkle
4. Which office class is the local central office	5
5. Which exchange is used to connect between central offices when a direct trunk is not available	Tandem
6. What component in the telephone set has the primary function of compensating for the local loop length	Varistor
7. What type of receiver is most commonly used in a conventional telephone handset	Electromagnetic
8. What component of the telephone set has the primary function of interfacing the handset to the local loop	Induction coil
9. Pulse Stuffing is used in TDM to __ the transmission rate between input channels	Equalize
10. The nominal value of the dial pulse break interval in milliseconds in US is	60
11. How many unique tones are used in 12-key dual tone multifrequency keypad	7
12. A 35 mm frame of film that measures 36 x 24 mm has an aspect ratio of	3:2
13. The bit rate of TDMA is __kbps	8
14. L600 mastergroup baseband has a bandwidth of ___kHz	2728
15. Minimum illumination recommended for reading is __lx	800
16. What is measured on a circuit where it is correctly terminated but does not have any traffic	White noise
17. Noise when measured across the tip and ring terminals of a network shall be ___dBrnCO	15
18. What is the highest frequency that can be generated by an IMPATT microwave diode oscillator	30GHz
19. What is the least expensive connector that is widely used for CATV, VCRs and TV sets	F-7 type
20. What is the typical output voltage of magnetic microphone	1mV
21. What refers to the cost effective standard based wireless solution that specifically supports low data rates, low power consumption, security and reliability and is also known as IEEE 802.15.4?	ZIGBEE
22. In April 2002, the IEEE published their 802.16 standard for “broadband wireless access” (BWA), more commonly known as ___.	WIMAX
23. What is the gamma of the picture tube of the television?	2.2
24. What is the signal rate of RS 232 normally used as interface between DTE and DCE?	20Kbps
25. What fiber optic wavelength is used because of an attenuation null at the wavelength?	1.3 microns
26. What is the standard IF frequency for picture used in TV receivers following NTSC standard?	45.75 MHz
27. What is the average maximum data rate for fiber optics?	50 Gbps
28. What is the commonly used telephone wire?	AWG # 19
29. How many mixers are there in an SSB receiver	2
30. What is the heater voltage of TV receiver picture tube	6.3 V
31. How many oscillators does a black and white TV receiver contain?	2
32. Shadow mask for color TV has about ___ holes	300 000
33. What is the typical value of the velocity factor of an open wire transmission line?	0.9
34. Which among the IEEE standard refers to the global specification for wireless LAN?	802.11b
35. What is the width of V blanking pulse?	1333 microseconds
36. What is the width of H blanking	10.2 microseconds
37. What is the GPRS uplinks data rate?	14 kbps
38. Using a single frequency sound wave to produce a 3D image of an object. It is usually viewed on a CRT	Acoustic Holography
39. The audio portion of a videotape has a bandwidth around	50Hz to 10 kHz
40. To avoid interference between adjacent satellites, geostationary satellites operating in C band must be separated by how many degrees?	2 degrees
41. The operating frequency range of low frequency CATV amplifier	1 Hz- 150 MHz
42. High frequency range of CATV amplifier	300 MHz- 50 000 MHz
43. What do you call the vertical edge distortion of screen image	Barrel effect
44. MPEG-2 data compression can reduce the amount of high-definition TV data by a ratio of	55 to 1
45. A satellite classified as BIG LEO, which is used for voice and data services, operates in what range of frequencies?	>10 GHz
46. Telstar 1 was considered as the world’s first active communications satellite. In what year was Telstar 1 launched	1962
47. A telephone, often an 800 toll-free number, which spells something, such as 1-800-EXCELRC is called	Vanity line
48. IMT-2000 is the standard family for 3G mobile communications systems. If it is called UMTS in Europe, what is it called in Japan?	J-FPLMTS
49. The encryption standard is a ____ -bit private key. (unclassified computer data)	56
50. Types of earth station	VSAT, short, long earth station
51. Long distance data transmission	21 to 4000 ft.
52. Medium distance data transmission	More or less 20 ft.
53. Cable modems are used in cable tv systems and provide data rates of typically between	3 and 50 Mbps
54. In fiber optics, VSR or very short reach is a physical layer specification that operates upto 10GHz over distances of less than __	300 m
55. The RS-232C has how many pins	25
56. Maximum speed on an RS-232 cable	20kbps
57. Local Multipoint Distribution system (LMDS) is a system developed for wireless local loop application, supports voice and high speed interactive data, with the potential to provide bandwidth as much as ___	500Mbps
58. Most popular standard for communication and connection between DCE and DTE	RS-232
59. Data rate of CSMA/CD	10Mbps
60. Bit rate of DS-1 signal over a T-1 line	1.544Mbps
61. LOS	VHF
62. Theoretical range of WIMAX	50km
63. Practical range of WIMAX	3-5miles
64. IEEE 802.15	Bluetooth
65. Wireless LAN	IEEE 802.11b
66. GPS was first used in what year	1978
67. 3G bit rate for stationary	2Mbps
68. 3G bit rate for high speed vehicle	144kbps
69. 3G bit rate for slow moving pedestrian	384kbps
70. In fiber optics, LED can provide light output in ___ window	All of the above (850 nm, 1300nm, 1550nm)
71. It is the term used to describe a GSM and EDGE based 200kHz Radio access network	GERAN
72. G3 facsimile equipment	X.38
73. Group 3 Fax machines	ITU-T T.6
74. In PC, infrared port (Infrared serial data link), used to synchronize with other devices. It can provide up to ____	1.5Mbps
75. When the PLL is locked the phase detector is…	0°
76. Voice channels in DS-2	96
77. Number of groups in supermastergroup (CCITT’s TDM hierarchy)	75
78. Ethernet bit rate for CDMA/CD	10Mbps
79. Teletext is ___ times faster than Telex	50
80. The Hertz antenna is predominantly using frequencies above	2GHz
81. It is the accidental transmission of VHF radio waves beyond the horizon that is probably caused by the temperature inversion at the lower atmosphere	anomalous propagation
82. Degree of protection of camera enclosure	Index of protection
83. 14400bps and 12200bps modem used on four wire leased line	V.33
84. _____protocol in X.25 for routing and addressing function similar to IP	Packet Layer
85. The function of the payload pointer is to facilitate synchronous operation to minimize network delay and to aid_____	All of the above
86. In data networks what occurs when the network runs out of capacity to pass all data submitted	Congestion
87. A process that condenses entire NTSC or PAL Video bandwidth into digital signals that can be recorded on tape	Adaptive range coding
88. In a single gun color CRT, What electron beam travels straight through the tube	Green
89. Ratio of the picture quality to the RF bandwidth	Bandwidth efficiency
90. Satellite……	Linear…..block and convolution…
91. Frequency range of fiber optic cable	100-1000THz
92. The gateway is a backbone network device that is operating in the ____	Network layer
93. Satellite position	55°
94. …. LPTV operates in the frequency band __	All of the above
95. Frequency range for wifi	11-54Mbps
96. iDEN	All of the above
97. Integrated Digital Enhanced Network (iDEN) is a mobile telecommunications technology, developed by Motorola, which provides its users the benefits of	All of the above
98. End-user-to-network interterface(s) in ISDN	All of the above (Basic access, primary access, broadband access)

Complete List of Communications Engineering Coaching Materials

Communications Engineering Coaching Materials

---