Communications Engineering Coaching Materials: Section 5 Module 12

This is the Section 5 Module 12 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 12

#	Questions	Answers
1	The HDTV has an aspect ratio of	16:9
2	The maximum frequency deviation in FM TV signal	25kHz
3	What is the mode of the waveguide is both the magnetic and electric field is parallel in the z-component	HE
4	What is the baseband frequency for basic super group?	312 – 552 kHz
5	What is the most commonly used antenna for satellite?	cassegrain antenna
6	At what speed do electromagnetic wave travel in free space	about 300 million meters per second
7	An electromagnetic field consists of	electric and magnetic field
8	the depth of an object submerged in a transparent liquid	always seems less than its actual
9	when a magnetic field is perpendicular to the surface of the earth, what is the polarization	horizontal
10	indicate which one of the following terms applies to troposcatter propagation	Fading
11	the grounds wave eventually disappear as one moves away from the transmitter because of	tilting
12	the shortest distance measured along the earth’s surface that a sky wave is returned to earth	skip distance
13	super refraction	ducting
14	commonly used for LNA	tunnel diode
15	channels 2, 4, 5, are	low band VHF
16	filter used for channel 2 to 13	band-reject filter
17	frequency for reverberation	500 Hz
18	space noise is observable at what range of frequencies	8 to 1.43 GHz
19	a mechanism or device which enables the TC camera to move in lateral and tilting motion	pan/tilt device
20	which is the first component of any MATV system to receive broadcast signals	antenna
21	time duration for horizontal trace	52 us
22	listing of the date and time of events, program etc malfunction and corrections in comm. Systems	log
23	the CCIR transmission standards for FM sound broadcast at VHF	Rec. 450.1
24	which of the class station is a regional channel	class III-B
25	CCIR standards for internal exchange of programmes on film for television	rec. 265.6
26	The channel for cable TV range frequency 5.75 – 11.75 MHz	T-1
27	The permissible power in kW of station II-A during nighttime is	0.25 – 50
28	MPEG -4 uses what media format	Divx
29	Glass tube of TWT in coating the aquadag _______	Provide attenuation
30	Maximum deviation ratio for TM	5
31	TV frequency band of channel 9	186 – 192 MHz
32	A means of beyond the line of sight propagation of UHF signals	Troposcatter propagation
33	Jet thrusters are usually fired to	maintains the altitude
34	The main function of a communication satellite is as a/an	repeater
35	A satellite stays in orbit because the following two factors are balanced	gravitational force and the centrifugal force
36	The maximum distance of an apogee of the ISS	358 km
37	What modulation is normally used with digital data?	QPSK
38	When the satellite are spaced 4 degrees of the 360 degrees complete circle, how many parking space or orbit slots are available	90
39	In ITU frequency allocation, the earth is divided into	3
40	What is the lifetime of ILDs?	50,000 hrs
41	Light goes from medium A to medium B at an angle of incidence of 40degrees, the angle of refraction is 30 degrees. The speed of light in B	is less than that in A
42	In a vacuum, the speed of an electromagnetic wave	is a universal constant
43	Distance near skip distance should be used for sky wave propagation	to prevent sky-wave and upper ray interference
44	Frequencies in the UHF range normally propagate by means o	space wave
45	Tropospheric scatter is used with frequencies in the following range	UHF
46	light of which the following has the shortest wavelength (red,yellow,blue,green)	blue
47	when a beam light enters one medium from another, a quality that never changes is its	frequency
48	a means of beyond the line of sight propagation of UHF signals	troposcatter propagation
49	type of radio wave responsible for long distance communication by multi skips is the	sky wave
50	System network Architecture uses what protocol	SDLC
51	EDGE stand for	Enhanced Data Rates for Global Evolution
52	AM type of emission	A3
53	Vestigial sideband emission	C3F
54	Fiber optics range of temperature during installation	0 – 60 degrees celcius
55	Range of Bluetooth	10 meters
56	Using GSM for EDGE, the date transfer rate is _____kbps	384
57	Multiplexing used for GSM, 1800 and 1900 MHz	CDMA
58	Most commercial satellite activity occurs in which band	C and Ku
59	when a magnetic field is parallel to the surface of the earth, what is the polarization	vertical
60	when a electric field is perpendicular to the surface of the earth, what is the polarization	vertical
61	local exchange area defined by the NTC that shares the same local exchange rates	local exchange service area
62	A sub-discipline of acoustics, it is the study of how sound is generated	Transduction
63	States the regulations on radio stations and communications	Act no. 3846
64	Frequency band of TDM	1900-1920 MHz ; 2010-2025 MHz
65	Numerical value of the gain of a n isotropic antenna	1.66
66	Maximum frequency deviation for FM	75 KHz
67	Frequency for color black	2300 Hz
68	Speech coding of 3G system	Adaptive multirate
69	Waveguide used by lower cut-off frequency is _____ attenuator	piston
70	Frequency band of industrial, scientific and medical purpose is ___ to ___ GHz	2.40 to 2.48
71	Class of radio station with 100kW effective radiated power	class C
72	Determining the amplitude of an FM sideband requires	Bessel function
73	SAW device can be used as	filter
74	Cordless phones beyond 300 ft uses how much power	10 W
75	Not an advantage of LEO satellites for wireless media	it uses digital signaling technique
76	Wi-Fi use	single carrier, direct sequence
77	Not a major section of laser	monitor
78	Noise reduction coefficient at perfect absorption	1.0
79	In fiber optics, splicing	active
80	Category 6 UTP has how many twisted pair	4
81	Advantage of PCM over PAM	superior noise immunity
82	How long is a 1Mbit image is transmitted using ISDN(64kbps)	120s
83	In power class E1, the nominal power radiated is ___ dBm	33
84	The ionosphere is a region of ionized gas in the upper atmosphere. The ionosphere is responsible for	long-distance radio communications
85	The main power source for a satellite are	solar cells
86	Most commercial satellite activity occurs in which band	C and Ku
87	Common Frequency used for Handy Phone	1.9 GHz
88	The lowest amount of frequency	resolution
89	The television picture tube magnetic field can be used for	beam focusing and beam deflection
90	AM image signal is rejected	prior to the mixer stage
91	The frequency of oscillation by a magnetron is mainly determined by	the dimension of each cavity resonator
92	In accordance with ITU specifications, the rate of the dispersion with wavelength for a a single mode fiber must be less than _____- ps/nm^2/km	0.95
93	Threshold point of QPSK is plus minus	0.875
94	Citizen frequency band radio service is _____	26.965 – 27.405 MHz
95	____ GHz/km	50 - 100
96	is a signalling message transmitted from the data communications equipment (DCE) indicating to the data terminal equipment (DTE) that it may begin data transmission	Clear to send
97		9-10
98		Videotext
99		30

Complete List of Communications Engineering Coaching Materials

Communications Engineering Coaching Materials

---