Communications Engineering Coaching Materials: Section 5 Module 14

This is the Section 5 Module 14 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 14

#	Questions	Answers
1	What is indicated by blinking in an LORAN system?	An error occurred in transmission
2	The primary coating of an optical fiber has a core diameter of _____ microns	250-750
3	The core diameter of a single-mode fiber optic available in the market	8 – 10 µm
4	Velocity that is the speed with which a constant phase is seen to be moving as a group	Group velocity
5	Dead Reckoning (DR) system used by helicopters	Doppler Reference Navigational System
6	Number of transponders of Philippine Agila II	30 transponders
7	Device used to connect non-ISDN equivalent to ISDN line	Terminal adapter
8	The bandwidth used by CDMA system	1.23 MHz
9	Superband is located above channel ___	13
10	Chrominance subcarrier frequency	1.8 MHz
11	Range of VHF transmitters	54 – 216 MHz
12	Angstrom is equal to __	10-4 µm
13	In CATV systems, the visual carrier is located at ___	1.25 MHz
14	According to NTC 03-03-2005A or the Rules and Regulations on Broadcast Messaging Service,Telcos with violations will have a penalty of ____per subscriber	P200
15	Department Order no.88, of MNTSC requires the supervision of an ECE in the operation and maintenance of a total of ___ stations or any other type of land stations	6
16	”cross-link”, the distance between two geostationary satellite (note: “crosslink” not sure.sorry)	60,000
17	Satellites that are newly launched have solar cells capable of supplying ___ watts	520
18	According to NTC 03-11-2005 or Registration of VoIP Service Providers and Resellers, Voip providers shall give as a performance bond, amounting to____	P5 million
19	The carrier frequency of FM station channel 288	105.5MHz
20	Camer lens aperture can be made smaller by “stopping down” the iris to an effective diameter of about 1/sqrt of 2 reduces light by ____	half
21	A sensor where external stimuli is used, allows to change optical path lengths, and also in the reinforcement/cancellations of light waves at the photo-detector	Birefringence sensor
22	A type of transmission that uses the connecting medium as a multi-channel device	Broadband transmission
23	A device used to connect different LANs to a common network	gateway
24	The power loss due to fusion splice	0.01dB to 0.1dB
25	The part of the ear that is auditory and has fluids	cochlea
26	The pitch to density relationship is given by: the change in frequency is ____	inversely proportional to the sqrt of change in density
27	A sensor wherein the birefringence is directly proportional to the square of electric field	Kerr cell
28	The minimum gain of channel 11 CATV	22dB
29	Interlacing used for pre-ISDN standard for basic rate access for ISDN environment	R interlace
30	VSAT operates at what band?	C-band
31	What is the most appropriate description for an ILS system?	An aeronautical radio navigational system that contains two information related to the runway
32	Which is not a hybrid analog and digital modulation technique?	Continuous-phase modulation
33	A modulation wherein a train of pulses	Delta modulation
34	What is measured in an OMEGA system?	phase
35	For a satellite in orbit, the two parameters must be balanced. These are ___	Gravitational pull and inertia
36	To stabilize a satellite in orbit, this is used	thruster
37	Broadcast station towers are painted __	White and orange
38	The superposition of two TEM wave	mode
39	Mirror-like reflection, a single direction of light when reflected becomes a single outward reflection, this phenomenon is called	specular
40	Camera lens that uses lead oxide	plumbonic
41	What height of an ionized layer is determined from the time interval between the transmission signal and ionospheric echo at vertical incidence?	Virtual height
42	A noise that lowers intensity with frequency	Flicker
43	An extraneous bit is added to the bit stream by a noise source	Glitch
44	Cause of slow rising white “hum bars” in the television	Bad filter
45	In error correction and detection, a process where additional bits are included in the bit stream	hamming code
46	Any subscribed or unsolicited message sent to a user without his/her consent and is sent by PTE or CP	Push message
47	The user tells all callers that the terminal is unavailable	Absent-user service
48	A type of filter that allows below and above frequencies	bandstop
49	Not included component	Synchronizing signal analyzer
50	Which diode is a popular microwave oscillator?	gunn diode
51	Advantage of TWT over Klystron	Wider bandwidth
52	For proper operation, a magnetron must be accompanied by a	permanent magnet
53	In wireless transmission, it is considered as medium range	IEEE 802.11
54	The camera control unit is located____	At the control room console
55	It is used to demagnetize TV sets	degaussing coil
56	Degaussing coil is located__	around the tube face
57	Burst noise is also known as____	Popcorn noise
58	Pulsed radar sets are used to find___	Range and bearing
59	Number of windows in an optical fiber that is available now	111
60	Firewire can connect together up to ____peripherals	63
61	At max sunspot activity, electrons/cm3 in E layer increases by___	50%
62	An antenna that can receive TEM wave polarized in all direction	Helical
63	Least luminous efficiency	Low wattage light bulb
64	Shortening effect of an antenna that makes it appear as if it were 5% longer	End effect
65	An antenna that is mounted on aircrafts	Skin antenna
66	What is the theoretical gain of a Hertzian dipole?	1.76dB
67	If the reflecting surface of a parabolic antenna has accumulated layers of dirt, what is the effect of this?	only negligible effect
68	When ½ of line scanning is used for scanning odd and even lines	Exact interlacing
69	If a mirror cannot be adjusted to view everything, one way to overcome this is by changing to	shorter focal length
70	Typical Speech power	10-1000µW
71	The industry that includes the design, operation and implementation with regards to space and air	Aerospace
72	Multiple access used by DECT	TDMA
73	The area in which no interference-free primary service is given by a licensed Broadcast Station	White area
74	Replaces PDH	SONET
75	Standard Noise temperature in Fahrenheit	62.6
76	First geosynchronous satellite launched in 1963	Syncom II
77	The Angle of I signal(broadcasting-color)	57deg
78	Earth’s base station output power to space	20kW
79	What do you call… 90deg at nose of ship	on starboard beam
80	Measured quantity in Doppler	speed
81	Frequency range of channel 11	198-204 MHz
82	Core diameter of step index multimode fiber	0.2 Angstrom
83	Land mobile service beamwidth	60
84	According to Act 3486, the maximum penalty for a person who commits three offenses are___	P6000 & 6years
85	Luminance(Y) combination	30% red 59% Green 11% Blue
86	NTSC standard sub-carrier frequency (color TV)	3.5795MHz
87	Scintillation occurs at what frequencies	4 and 6GHz
88	For sound carrier not to overlap with higher visual carrier, it must be attenuated by___	13-17 dB
89	Limits the 3 dimension propagation to only a single direction	waveguide
90	Sunspot occurs every how many years	11
91	The part of EM wave that affects matter when it comes in contact	electric field
92	It is the propagation by reflection instead of conduction	waveguide
93	Ear is sensitive at what frequency	1-5kHz
94	Camera output signal without sync____	Non composite video
95		Frequency allocation
96	Number of bits present in 16 combinations	4
97	Solar cells are used for satellite power requirements. During eclipse, ____ batteries are used as back-up	Nicad
98	Photonics are used in very large frequencies, mainly in the range of ____	Terahertz
99	A type of microphone wherein a tiny amplifier is built into it during casting that is called head amplifier	Condenser
100	The part of a fax machine, which consists of rectilinear ribs, determines the position of the scanning lines of record medium	Writing Bar

Complete List of Communications Engineering Coaching Materials

Communications Engineering Coaching Materials

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