Download Which of the following is a method to investigate the stability of

Which of the following is a method to investigate the
stability of closed-loop system?
a. Routh-Hurwitz Criterion
b. Bode Diagram
c. Nyquist Criterion
d. All of the above
Which of the following form of propagation is directly
affected by surface weather conditions?
Tropospheric Scattering
What is relationship of the resistivities of ferrite and metals?
Ferrites have resistivities of 106 times
more than the resistivity of metal
What program stimulates individual machine instructions,
usually in a machine other than the one being stimulated?
Simulator
A LED that emits green light.
GaP
What type of material in LED construction emits infrared
radiation?
GaAs
What type of material in LED construction emits red or
yellow visible light?
GaAsP
What type of material in LED construction emits red or
green visible light?
GaP
If a change in resistance in nonlinear with respect to change
in temperature then the parameter is called _______.
Resistance Temperature Characteristic
What is a slow moving “cord like” mass of plasma across
the sun’s surface?
Filament
What is the approximation intensity of the magnetic field at
the earth surface at the equator?
32,000 nT
MOS-controlled thyristor in to-218 plastic pack are available
in what ratings?
600 V and 50 A
The first Philippine company that operates GPRS.
SMART Communications
Refers to extreme infrared.
15 m to 1 mm
The lifespan of the Philippine Mabuhay Satellite.
15 years
What is the intensity of the magnetic field at the earth’s
North Pole?
62,000 nT
Refers to far infrared.
6 m to 15 m
The first Philippine Satellite (launch from China) was launch
on what date?
August 18, 1997
Diode sensor is a microwave sensing element that can be
operated at what range?
Greater than 18 GHz
What is considered the forth generation of the Bluetooth
specification?
Version 1.2
What do you call a satellite weighting 1 kg to 10 kg?
Nanosat
A capacitor terminology that refers to minute and rapid
fluctuations of capacitance.
Scintillation
What is the orbital location of the Philippine Mabuhay
Satellite in the geostationary orbit?
146º East Longitude
Wave in which the wavelength is measured from successive
compression or rarefaction.
Longitudinal Wave
Wave in which the wavelength is measured from successive
crest or trough.
Transverse Wave
The absolute unit of inductance is determined by
_________.
Length
Refers to the splitting of spectral lines due to the influence
of strong magnetic field.
Iceman Effect
What is the maximum output power of a Class A FM?
0.1 to 3 kW
What is the maximum output power of a Class B FM?
5 to 50 kW
What is the maximum output power of a Class C FM?
25 to 100 kW
The multiple access technique used in Bluetooth Wireless
Technology.
Spread Spectrum
What is the maximum antenna height of a Class B FM?
500 m
What is a slow moving large mass of plasma on the sun’s
surface?
Prominence
What is the maximum antenna height of a Class C FM?
2000 m
Which of the following is the objective of a closed-loop
system?
a. All of the above
b. Stability
c. Steady State Tracking
d. Distribution Rejection
A former TV broadcasting channel that is now used for other
purposes.
Channel 83
What is the maximum antenna height of a Class A FM?
300 m
At what particular wavelength is solar flux measured?
10.7 cm band
What is not a standard color in a potentiometer indicator
system?
Blue
In a potentiometer indicator system, what color relates
always the counter clockwise limit element?
Yellow
In a potentiometer indicator system, what color relates
always the clockwise limit element?
Green
In a potentiometer indicator system, what color relates
always the wiper?
Red
A spot on a sun’s visible surface where the magnetic flux
lines converge.
Sunspot
In CDMA, what is the process or spreading gain if the
transmitted bandwidth is 5 MHz and the baseband BW is 2.5
MHz?
Sol’n.
GP = 10 log BRF + 10 log 5/ 2.5
BBB
GP = 3 dB
Which of the following musical instrument is considered
dissonant?
7:8
There are how many orbital planes which are equally spaced
in a GPS operational constellation?
6
How much is the fine of unauthorized servicing of mobile
phones?
P 5,000.00 per unit
What is the first modulation used in SB microphone?
Absorption or loop
What do you think is the disadvantage of using gridmodulation over plate modulation?
Low-efficiency, difficult to adjust
What is connected by three small joined bones in the airfilled … air to the oval window of the inner ear or cochlea, a
fund-filled spiral coil about one and a half inches in length?
Eardrum
For greatest accuracy, what should the input impedance of a
VOR be?
Should be as high as possible
Any emission from a transmitter other than the carrier and
sidebands required by the modulation scheme in use.
Spurious Signal
What is the annual spectrum user fee (SUF) for the allocated
and assigned unpaired 3G radio frequency band for each
additional MHz or a fraction thereof in excess of the first 5
MHz but not exceeding 10 MHz?
P 6 Million per MHz
What is a voltage-series circuit? It is a series-applied
Voltage-derived feedback circuit
What is the used for an antenna with small BC band
receiver?
High Q loopstick
What is the main advantage of direct PM over PM
modulation?
Fewer Multipliers
What is produced when the audio frequencies are distorted
in the receiver?
Harmonics
What refers to the incident or forward power that is applied
to a line and combines with the reflected power that forms a
pattern of voltage or current in the line?
Standing Wave
What is the range of frequencies for the radiotelegraph
transmitter?
10 kHz to 200 MHz
Binary pattern of 1’s and 0’s arrange in random.
Pseudorandom Code
Why is it important for a base station to be able to control
the power level of the mobile station transmitter?
Interference with adjacent cells due to the
same frequencies can be reduced by using low
power levels as possible
Why are data rates in 3G system higher in stationary than in
mobile phone user?
Because of transmission impairments of
robust
modulation scheme is used only for
low data rates
If an audio signal is lost on higher frequency, what can be
added to it to flatten the response?
Equalizer
How introduce the idea of using a satellite as relay stations
for the international microwave telephone system in 1945?
Arthur Clarke
What is the unique form of encoding that relies on the
individual bits to predict the behavior of the incoming
signal?
Continuously Variable Slope
Delta
Which of the following material has the highest absorption
coefficient for sound waves?
CELOTEX
What frequency band greater than 10 GHz that is reallocated
by NTC for broadband wireless access for fixed, nomadic
and mobile network?
10,150 – 10,650 MHz
What is a combined mixer and local oscillator that uses one
transistor, or tube or both?
Autodyne Converter
The ratio of one utilized flux to the luminous flux leaving
the lightning fitting?
Utilance
A network using a microwave for two-way transmission of
telephony, television and high speed data.
Local Multipoint Distribution System
What multiple access method that GPS uses?
CDMA
The speed of the geostationary satellite.
6879 statute miles per hour
What is the official name of
MPEG-7?
Multimedia content Distribution Interface
In sky wave propagation, what is the most practical
frequency that can be used with the least problems?
Optimum Working Frequency
What type of amplifier has poor selectivity?
Wide Bandwidth Amplifier
What is measured in a lie detector test?
Skin Resistance
What is the typical service factor of motors?
1.15 – 1.4
What is the annual spectrum user fee (SUF) of allocated and
assigned paired 3G radio frequency bands for each MHz or a
fraction thereof in excess of the first 15 MHz?
P 15 Million per MHz
What is the typical bandwidth of a single mode step index
fiber?
50 to 100 GHz/ km
What is the bandwidth of “Wireless Fidelity” of WiFi?
11 to 58 kbps
What is the standard cladding diameter of single mode step
index fiber which is considered as the most widely used of
today’s wideband communications arena?
125 m
What frequency band greater than 3 GHz but less than 5
GHz that is allocated by the NTC for broadband wireless
access for fixed nomadic and mobile network?
3400 to 3600 MHz
What is the annual spectrum user fee (SUF) of allocated and
assigned paired 3G radio frequency bands for each MHz or a
fraction thereof in excess of the first 5 MHz but not
exceeding 10 MHz?
P 8 Million per MHz
What is an open standard that allows PC’s, peripherals,
cordless telephone, and other consumer electronic device to
be connected and interoperated with one another without the
complexity of insulating new wires?
Shared Wireless Access
Protocol
What microwave circuit is used with the conjunction with
semiconductor microwave device consisting of tow metal
planes separated by the thickness of a dielectric in the
middle in which metal strip has been buried?
Stripline
In acoustics, why is reverberation important in all types of
music?
Because it gives warmth and sonority and a
sense of power
In 1972, InterNetworking Working Group (ING) became
one of the first several standards-setting the growing
network which later became the internet who was elected as
the first chairman of ING and became the father of the
internet?
Vinton Cerf
What fixed station uses a multiplex digital radio link as a
segment in a local loop to provide wireless telephone service
to remote places where it is impractical to provide wireline
telephone service?
Basic Exchange-Radio Telephone
Service
In GPS, how many NavStar satellite are operating at 11,000
miles above earth’s surface?
24
In QPSK modulation, how much is the distance error
between signaling points for signal peak amplitude of 1.2 V?
Sol’n.
d = ( 2 sin 180/M ) X D ; M = 4 , D = 1.2V
d = 1.7 VP
The specified zone of TV broadcast station is the area
extending from the reference point in the community by
which the station is licensed or authorized by the NTC.
56 km
Bluetooth Wireless Technology was first conceived by
which of the following companies in 1994?
Ericsson
Which of he following frequency is most portable band to be
used in HF propagation?
a. 3.5 MHz
b. 7 MHz
c. 14 MHz
d. All of the above
In acoustics, which of the following acoustical defects that
should be avoided?
Long delayed echoes
The first artificial satellite, Sputnik 1 is ___________.
About the size of basketball
Who invented the programmable logic array in Monolithic
Memories Incorporated 3 (MMI)?
John Birkner
What type of rectifier filter that has high output voltage but
poor regulation, poor transformer utilization factor and high
current peak?
Capacitor Input Filter
In oscillator circuits, the effect when there is change in the
generated frequency due to a change in the load?
Frequency Pulling
NTC extends the UHF TV broadcast band and designates
the _______ band for UHF TV broadcast service.
674 – 728 MHz
In computer, what contains instructions and data that the
hardware manipulates the useful works?
Software
______ is the work in electron volts needed to pull one
electron from an isolated uncharged atom.
First Ionization Potential
What is the annual spectrum user fee (SUF) for the
allocation and assignment for the paired 3G radio frequency
band?
P 5 million per MHz
In LSI circuit design, what simulation is considered at the
top most level?
Architecture Simulation
The range of resistivity in conductors.
10-6 to 10-4 –m
What is the classification of linear beam microwave tube
such as klystron and TWT?
O-type device
Who once said “I sell here with the world desire for power”?
James Watt
What area in which the geosynchronous satellite cannot
cover?
81º north and south latitude
PLA was invented at signetics in 1975 by ________.
Napoleone Cavlan
Which of the resistor is the most voltage-sensitive among
others?
Carbon Composition
Who invented the term “byte”?
IBM
What capacitor class includes ceramic dielectrics commonly
used in capacitor for coupling, bypass and decoupling
circuit?
Class II
What metal is commonly used in storage cell?
LEAD
Your foemen ask you to measure resistance in field lines.
What would you use?
Megger
What is the usual transmission power output o most
Bluetooth products?
1 mW
The range of resistivity in insulators.
109 to 1025 -m
What company built the first cellular telephone in 1924?
Bell Laboratories
What is the four section of a power supply?
Transformer, Rectifier, Filter, Regulator
What phenomenon is observed in closed loop systems in
saturation, where the input-output amplitude ratio and phase
angle as a function of frequency exhibits a sudden
discontinuity?
Jump Resonance
What oscillator is peculiar in nonlinear devices?
Limit Cycle
The range of resistivity in semiconductors.
10-4 to 109 –m
In color TV receiver, what is he cause or source of trouble
when there is no color?
3.58 MHz Bandpass Amplifier
GaPZn LED emits what color?
Red (690 nm)
What refers to the amount of current will sense full scale
deflection?
Ammeter Sensitivity
The breakdown voltage of mercury vapour discharge tube is
______ than its potentials.
Higher
Used to reduce even order harmonic.
Push-Pull
What executes a program one or a few instructions at a time
which allows the programmer to see small part of the
program, thereby isolating programming errors?
On-line Debugger
What is a combined mixer and local oscillator that uses one
transistor or tube or both?
Autodyne Converter
A reduction in the effective resistance of a resistor which is
operated in the ……….
BOELLA Effect
The ratio of the utilized flux to the luminous flux leaving the
lighting fitting?
Utilance
Wet etching was the most popular etchant in the early
development of the IC. What etchant is use in etching the
silicon film IC?
Planar Etchant
What happens to the inductance of the coil if the
permeability of the core increases?
Inductance Increases
In oscillator circuits, what do you call the effect when the
change in frequency is caused by the change in the anode
current or voltage?
Frequency Pushing
What types of logic have states that are continuous from
“totally false” through neutral to “totally true”?
Fuzzy Logic
In digital data transmission using delta modulation, what is
the normal cause of error in the demodulated signal?
Slope Overload
What is the minimal operating frequency of UWB (Ultra
Wide Band)?
5 MHz
What is the electronic method of reducing or removing
unwanted sound by producing pressure wave of equal
amplitude but of opposite sign to the unwanted sound?
Active Noise Control
What is the additional SUF (Spectrum User Fee) imposing
to 3G network operation for the additional 100,000
subscriber/users in excess of the first 4 million scriber?
P 2 million
What is the annual spectrum fee for the allocation and
assignment of unpaired 3G radio frequency band for the first
5 MHz?
P 3 Million per year
What is the decibel level of a normal conversation?
60 dB
What type of antenna is also known as wave antenna?
Beverage antenna
The NTC reallocated and assigned the frequency bands of
_____ and ______ for use of telemetry and other similar
applicants.
481.250 & 481.475 MHz and
486.250 & 486.475 MHz
What high power microwave tube was first described in
USSR in the late 1970’s that is capable of producing power
that exceeds 1 kW CW over 100 GHz frequency?
Gyrotron
Which microphone will damage by exposing at high
temperature above 52 ºC?
Crystal Microphone
A cross modulation of conductors in a multi-layered cable
can be detected using ___________.
Varley Loop
The illumination needed for skilled bench workers is
between ____________.
60 to 100 lux/m2
What is defined as the effect in dielectric materials similar to
hysteresis found in magnetic material?
Magnetic Hysteresis
FCC’s digital radio is operated at __________.
2.310 to 2.360 MHz
What circuit breaker opens a circuit even if the operating
mechanism is held on the ON position?
Trip free circuit breaker
How many stable states are there in a flip-flop?
2
What is the operating temperature of a class A motors?
105 ºC
What do you call the connection of information inside a
computer for easy access?
Database
Emission for FM stereo multiple signal.
F3E
Point of reference of a JFET.
Source
Also known as “Skip Zone” for US military.
Blind Zone
A decode counter ______________.
Counts to 9 and resets on its next counts
Specific emission for tantalum cathode material of vacuum
tubes.
0.5 – 1.2 A/cm2
How many circuits can a DPDT switch simultaneously
control?
2
Maximum ambient temperature of an EIA precision resistor.
125 ºC
A maximum motor end play is about ________mm.
0.4
Used to etch Molybdenum film.
Dalton Etchant
Broadband Wireless Access (BWA) commonly known as
_____________.
WiMax
Ribbon microphone is an example of what?
Pressure-Gradient microphone
What limits the output amplitude of a comparator?
Bounding
Usual undesired spacecraft system to variations ……space
environment?
Satellite Anomaly
Inventor of cavity magnetron, a high power microwave
oscillator.
Randall and Boot
What common electronic component is not included in IC’s?
Inductors
What refers to a relatively new category wireless
communication which uses laser operating in the nearinfrared region of the light spectrum?
Free-spaced Optics
Made some observations about sound reverberation and
interference to somewhat started resulting the started of the
subject acoustics.
Marcus Pollio
What is the maximum spectrum user fee for allocated and
assigned “paired” 3G for frequency bands for each
additional MHz or fraction thereof in excess of the first “10
MHz” but not exceeding “15 MHz”?
P 10 Million per MHz
What microwave transmission line is analogous to parallel
wire line consisting of top strip and its image below the
ground plane?
Microstrip Line
Refers to provision of voice communication using internet
protocol (IP) technology?
Voice Over Internet Protocol
Which ionosphere layer was formerly called the Appleton
layer?
F2
What capacity terminology refers to the ratio of the increase
in capacitance when another dielectric replaces the vacuum
between two electrodes?
a. Relative Capacitivity
b. Relative Permittivity
c. Dielectric Constant
d. All of the above
What is the typical TV transformer flyback?
10 – 20 kV
What satellite frequency band uses for DBS has a downlink
frequency of 11.7 to 12.5 GHz?
Ku band
In fiber cables, typical light scatter loss is 2.5 dB at
_________ nm of light wavelength.
820
Local Multipoint Distribution Service (LMDS) operate at
what frequency?
27 GHz and 31 GHz
In Asynchronous Transfer Mode (ATM) cell format, what
indicates node source and packet distribution?
Virtual Channel Identifier
What antenna is otherwise known a wave antenna?
Beverage Antenna
Ultra Wideband is a short-range that will be used to transmit
data between devices over distances as much as
__________foot.
20
What is the minimum spectral operating frequency of Ultra
Wideband (UWB)?
500 MHz
Wireless Internet Service Provider uses what technology to
provide internet access to airport, hotels, convention centers,
coffee shop, and other public places?
WiFi
In cable TV broadcasting, primetime is a five-hour period
from _________ to __________ local time.
6:00 PM to 11:00 PM
What propagation is commonly known as a cause of
“Shooting Stars”?
Meteor Scatter
Double-tuned IF transformer has a coupling factor of 0.02.
Calculate the bandwidth o transformer at a frequency of 5
MHz.
Sol’n.
Overall BW = kOPT f; k OPT = 1.5 kc
= 1.5 (0.02) (5 MHz)
Overall BW = 150 MHz
________ is a code that indicates the exact location of the
item data to be stored or acquired from the computer.
Absolute Code
What element is used for plasma deposition o amorphous
silicon in IC manufacturing?
Ar (Argon)
What transformer operates at 100 – 150 kHz?
Converter Transformer
What factors affect air absorption?
Volume of air, Relative Humidity, and
Sound Frequency
What is a precision component which resembles a small
motor and has an output voltage proportional to its shaft
rotational speed?
Rate Generator
What standard allows a mobile phone to access specially
tailored websites?
WAP
What is the injection of large mass of plasma which is cause
mainly by …..?
CME
What is the sound pressure level of a rock concert?
120 dB
Which of the following is considered as short wave radio
signal?
3 – 30 MHz
The first artificial satellite sputnik 1, to how many minutes
to orbit earth?
98 minutes
What is the final stage of the evolution of the GSM
Standards?
EDGE
In a waveguide coupler, the loop coupler for a magnetic
field is rotated at 35º to the field. What percent of maximum
is the coupling?
Sol’n.
Coupling = sin 
= sin 35º
Coupling = 57.3%
A software of tool that interprets high-level language
program one statement at a time.
Interpreter
An instrument that can measure the concentration of
substances by absorption of nearly monochromatic radiation
of wavelengths selected by the filter of by simple radiationdispersion.
Absorptiometer
What class of FM station has an ERP of 100 – 3000 W?
Class A
What is the beamwidth of a symmetric pattern antenna with
a gain of 40 dB as compared to an isotropic radiator?
Sol’n.
 = 203 / log-1 (40/20) = 2.03
An MPSCP is issued to a qualified applicant with a validity
period of how many years?
1
Channel 23 occupies what of the frequency bands?
524 – 530 MHz
What is the approximate critical frequency of F2 layer?
8 MHz
What spread spectrum multiple access which is used in
Bluetooth Wireless Technology?
Frequency Hopping
Given a 635 s vertical retrace time, how many complete
horizontal lines scanned in a vertical flyback?
10
What is the typical power of educational FM station?
10 W
Project Diana of the U.S. DOD was the first project to use
the moon as a passive repeater of radar signal, it was
operated when?
January 11, 1946
What technology is the foundation of 2G and 3G services?
CDMA
What is caused when a color signal is interpreted as
luminance, producing a structure of fine dots?
Cross Color
What is the maximum height of a CB antenna?
60 ft from the ground, 20 ft from the
building
When a ferrite is subjected to magnetic field from a
permanent magnet, the electron spins experience what
phenomenon?
Precision
What do you find at the center of a star topology?
A hub or a switch
A gas used in most jet thrusters?
Hydrazine
In broadcasting, the geographic adjacent station must be
spaced at least _________ channels to provide sideband
interference operation.
3
A signaling path provided by the cable TV system to
transmit signals of any form a subscriber terminal to any
point in a cable system.
Class IV Cable TV System
The frequency of a visual carrier of CATV channels shall be
maintained at _________above the boundary of CATV
channels?
1.25 MHZ + 1.25 kHz
What are pulses used for vertical blanking or voltage signal,
which produces retrace?
Equalizing Pulse
In TV system, what is the crystal ringer circuit used for?
AFPC with color oscillator
What is a self generated oscillation in an RF amplifier,
which is not equal to the tuned frequency of the RF
amplifier?
Parasitic Oscillations
What digital circuit is used in bit splitting?
Shift Register
What terminal can be worked anywhere using a variety of
RF standards for fixed mobile and even used in satellite
operation?
Universal Personal Telecommunications
Terminal
What standard in North American is the direct sequencing
spread-spectrum system, which is also a digital cell phone
standard?
IS – 95
What are the two types of network software?
Peer to peer and Client Server
What layer in the ionosphere that has an approximate
nighttime range of 4130 km?
F2 Layer
What is used to a geo synchronous satellite to attain its final
circular geo stationary orbit?
Apogee Kick Motor
What is the conduction angle of class B amplifier?
180º
In application of mobile phone service center permit, one
should submit a resume and an employment certificate of
how many registered electronic technician by the applicant
in a full time basis?
1
What is the contrast control of a TV system?
Video Amplifier
What is necessary to control the HDTV signals to be
transmitted within the exciting 6 MHz bandwidth signal?
Compression of Data
What is a strange looking antenna, which is a combination
of horn and parabolic antenna and sued in terrestrial
microwave links?
Hog-Horn
What does POP3 in internet language stands for?
Post Office Protocol Version 3
What resistor has a typical flicker noise voltage of 0.01 to
0.2 µV?
It ties up one computer as the network file
server
In CATV system, a constant voltage regulator must be
provided to regulate the power supply of head-end
equipment to within _______of the supply level.
+ / - 10 %
What navigation system in now standard equipment on most
planes, ships, and submarines?
Inertial Navigation System (INS)
Which of the following camera tube has the minimum lag?
Plumbicon
Why is earth disk antenna generally parabolic in shape?
To maximize gathering of low power signals
What is BFO in SSB receiver called?
Carrier Oscillator
What camera tube uses lead oxide for the photoconductive
……..?
Plumbicon
What hue color is for sync pulse?
Yellow Green
What do you call a short sequence of bit sent typically 128
bits in digital signature?
Hash
What is the IMT-2000 maximum data rate for mobile user in
a high-speed vehicle?
144 kbps
In CATV system, harmonic (aural) distortion should be no
more than _________at 50 Hz to 15 kHz with +/- 25 kHz
deviation?
1%
In CATV system, what is the maximum noise figure without
equalizer at 54 MHz?
7.5 dB
What is the amount of sound attenuation offered by the wall,
ceiling and floor?
Transmission Loss
What characteristic in a modulating signal that is
proportional to the amount of frequency deviation in the
carrier frequency in FM transmitters?
Amplitude
What is the main purpose of buffer amplifier?
Amplify and Isolate
Why is amplitude variation prevented from reaching the FM
receiver?
Because it can degrade the noise
performance of the receiver
Where does most of the gain and selectivity in a
superheterodyne found?
The IF amplifier
What is the dielectric constant of a polyethylene insulator?
2.27
What is the most common filter used in SSB?
Mechanical Filter
What radio transmission process where the message or video
communications are sent to the radio channels that changes
frequencies in a predetermined order?
Frequency Hopping
One of the following is not a ground based navigational
system?
Transit
The first satellite Sputnik 1 was lunch in what year?
1957
What do you call a person who0 provides password for
computer users in a LAN?
Network Administrator
Digital data can be sent on a telephone system by?
Converting it to analog first
What oscillator whose frequency is controlled by a binary
number in an internal register?
Numerically-Registered Oscillator
What do you call the process of firing the rockets in
underground control to maintain or achieve the orbit?
Station Keeping
In TV, picture information is transmitted in a separate carrier
located at __________lower frequency than in sound carrier.
4.5
In CATV system, vestigial response should be _______at …
and _______ at adjacent video/audio frequency?
-20 dB, -40 dB
When was the commercial cellular system first operated?
October 13, 1983
What is the efficiency of the parabolic antenna?
55 %
How is fiber grating produced?
By illuminating the fiber with ultraviolet light
A licensed and registered ECE can apply for professional
electronics engineer if he is registered how many years after
the effectivity of R.A. 9292?
7 years
Which of the following is the nearest star in the solar
system?
Proxima Centauri
Why is the fading J3E signal distorts less than fading A3E
signal?
It is not beating against fading carrier
A mandatory 24hour ship to shore communication from
1810 to 1812 were established by the United States, Great
Britain, and other maritime nations as a direct result of the
sinking two famous ships, which of the following is the two
ships?
Republic and Titanic
What is the signal sent by the network calling telephone in
order to indicate that the called telephone is ringing?
Ringback Tone
What protocol uses the checksum method in error detection?
XModem
What communication device, which allows high-speed
access to wide area network such as internet via cable
network?
Cable Modem
ICT…means?
Information and Communication
Technology
The maximum radiation from an electronic equipment
should not exceed _______meter per week.
100
Depending on the terrain, a microwave system uses line of
sight propagation and may require repeater approximately
every _______ km.
40
What is referred to as the trapped gas pockets inside a fiber
optic cable?
Blooming
A type of card with embedded integrated circuit with
functions that can be used in storing subscriber information
in a PCS system?
Smart Card
What is the accuracy of a LORAN C long-range hyperbolic
radio navigation system?
¼ of a mile absolute and less than 100 ft
relative
What is the system that allows the user to access documents
from widely separated sources in the internet using the
common interface?
World Wide Web
A traffic model, which is based on the assumption that a call
cannot immediately satisfied, is held by the system until
served or terminated?
Poisson
What is the technique employed in networks to avoid
accidental flags?
Bit Stuffing
What is the advantage of optical fiber made up of plastic?
Inexpensive and more flexible
What law creates MTRCB?
P.D. 1986
What is the circuit that permits selective signaling by
allowing lower frequency tones to control the squelch?
Continuous tone control squelch
What is the smallest data block that can be transmitted
through the network?
Packets
In RADAR system, _______is the electromagnetic energy
received by the antenna after reflecting to an object?
Radar Echo
How much filing fee in the application of MPSCP or
MPDP?
P 180
What is another name for pink noise?
Flicker Noise
What is the typical range of velocity factor in coaxial cable?
0.6 – 0.8
What is the frequency separation between the forward
channel and the reverse channel in a cellular communication
system?
45 MHz
In cellular system, how many cells are there in frequency
reuse plan?
7
What is the tone produced by a sound source other than the
fundamental tone?
Sidetone
What is the minimum ratio of a signal level to the noise
level, and signal level to the unwanted co-channel signal..?
36 dB
A signaling path provided by the cable TV system to the
subscribers’ line for TV signaling …..
Class 2 Cable TV Channel
What is the term for periodic variation of refracted index
along the length of the wire?
Fiber Grating
NTSC has 525 lines with number of frames. For moving
pictures, how many lines are scanned per frame in every
second?
30
How much is the permit fee for MPSCP or MPDP?
P 1,200.00 per year
Why is it difficult to produced music transmission with a
phase-shift SSB?
Because it is difficult to produce 90 degrees of
phase-shift
Whit is the digital audio compression that substitutes MP3
audio?
Dolby AC-3
What is the primary purpose of speech processing?
To make sure that overmodulation does not
occur
In Klystron, what do you call the cavity that removes some
of the energy from the electron beam and transfer it into the
form of microwave energy to the output?
Catcher
Obvious conveyor of information.
Speech
What devices are inserted into a telephone channel if the
total net loss of the trunk circuit exceeds about 2.5 dB?
Echo Suppressors
The orbits of GPS satellite are nearly circular with
inclination angles of _______degree relative to the equator?
55º
How much of the emission ….bandwidth of the transmitter?
99 %
At what range does TV signal occurs?
VHF and UHF
What refers to any sonic, infrasonic, and ultrasonic wave?
Radiation
What is the main cause of image interference?
Poor receiver selectivity
Operation efficiency of Class C amplifier?
100%
In a PM system, when is PM change to FM?
First amplifier after modulator
What is the modulation frequency that is most noise
resistant?
PCM
What amplifier that amplifies optical signal directly with
changing it to electrical form?
Optical Amplifier
IEEE 802.11b is the standard used by what Ethernet
service/access?
WiFi
What is combined mixer and local oscillator that uses a tube
or transistor of both?
Autodyne Receiver
IEEE 802.15 is the standard used by what technology?
Bluetooth
All color in a color test signal is modulated at 75 % except
___.
Gray
IRIDIUM satellites are a constellation of 66 low earth orbit
satellite, which are located at what particular height from the
surface of the earth?
780 km
How much permit fee for authority to import cable TV
equipment, spare parts and accessories?
P 100.00
What is the listening period of Ethernet LAN CSMA/CD
protocol?
9.6 s
What do you call the short message that is sent in a ring
network at each node in turn?
Free Token
Why must geostationary satellite orbit also equatorial?
So that it will be synchronous
What is the oldest modulation?
Amplitude Modulation
What is the science in measuring of light visible to human
eye?
Photometer
What circuit in a differential peak detector IC that
temporarily stores the peak value of an input sine wave?
Peak Detector
What is the typical vidicon dark current?
0.2 A
Why might more power in transmission line that out of it?
Line Losses
What refers to the number of symbols per second?
Baud Rate
What refers to the period of time that each chance in PAM
system is sampled once?
Frame
In TV, what is amplitude modulated for picture carrier?
Video Signal
What is used in long distance transmission?
Coax
Why is geostationary satellite unsatisfactory for region near
poles of the earth?
The angle of inclination is too low for
these regions
Maximum bit rate for fiber optic cables?
10 Gbps
What is the center impedance of a half wave antenna?
73 
In the operation and maintenance of cable TV system, you
need a ________.
Duly registered ECE
Policy guidelines authorized public telecommunications.
E.O. 59
What is the relation between crosstalk in PABX and
crosstalk in Key Telephone System (KTS)?
The same
Three –point tracking can be achieved with _______?
The padder capacitor
The velocity factor in transmission lines vary from ____ to
____.
0.5 – 0.9
What increase in the network capacity can be achieved by
3G wireless system?
70 %
What is the major benefit of DSB and SSB?
Higher power in the sidebands
In bit oriented protocols SDLC and HDLC, which sequence
represents the flag?
01111110
Why is frequency reuse important in cellular system?
Because cellular system increases their trace
capacity in reusing frequencies in relatively
small distance
Which is not a common GSM frequency band?
GSM 400
For TV system, the horizontal flyback is 10 percent. This
equals to _______.
6.4 S
What is the term for the bus that connects peripherals like
wireless modem and high speed video cameras into the
computer?
Firewire
What two frequency bands are allocated for the used of
IMT2000 or 3G mobile telecommunications in the
Philippines which are already assigned to existing CMTS
operators?
825 – 845 MHz &
870 – 890 MHz
What is the bandwidth of an AF filter for AM music?
5 kHz
What splicing is performed by joining two fibers end wither
by clamping them within the structure of by gluing them
together?
Mechanical Splicing
In TV receiver, what type of convergence is provided by
adjusting the permanent magnets?
Static Convergence
What is the maximum power of Class III analog mobile
phone?
3W
How will the cross modulation be stopped or decrease?
Using filters or wave traps
What radio system was developed to provide high speed
packet data access in GSM network?
GPRS
In SSB, the transmitter output is expressed in terms of
_____?
Peak Enveloped Power (PEV)
FM BC uses _______ polarization.
Horizontal
What are the frequency limits of the 6-m band in the ITU
Region 2?
50 – 54 MHz
Sunspot Cycle occurs every how many years?
11 years
Acoustic is derived from?
Akouieine
Satellite that weights 10-100 kg?
Microsat
K-index which means Very Severe Storm?
K7
K-index which means Extremely Severe Storm?
K9
What is the frequency range for the GSM 1900 band?
1930 – 1990 MHz
Wireless Internet Service Provider uses WiFi Technology to
provide internet access to the hotels, airports, coffee shops
and other public places. WISPs can provide internet access
of speed up to ________for users within the antenna range.
11 Mbps
What is the first satellite to carry a creature in outer space in
November 3, 1957?
Sputnik 2
All applicants of the 3G Radio Frequency Band must post
performance bond equivalent to what amount?
P 300 Million
Formula used in getting the reverberation time for
absorption coefficient of less than 0.2.
Sabine’s Formula
The Short Message Service has the ability to send and
received text messages to and from mobile phones. The first
short message was sent from a Personal Computer to a
Mobile Phone on the GSM videophone network in United
Kingdom on what date?
December 12, 1992
GSM, CDMA, IS 95 and IS 136 belong to what generation?
2G
What class of mobile phones can be connected to both
GPRS and Bluetooth?
Class A
A special ground–level meter that is used for counter
metering continuous cosmic noise?
Riometer
At what particular wavelength is solar flux measured?
10.7 cm band
What receiver type of transmission that is named after the
peculiar between Europe and North America?
Transatlantic
Intelsat communication system used FDMA of command
assignment system developed by COMSAT satellite.
Intelsat IV
What is the color of the neutral in a 3 core flex cable?
Blue
Who invented the Leyden jar, which is the first capacitor?
Peter Van MusschenBroek
In microwave system, what is the multipath effect of a
distance 30 km operating at 6 GHz with an objective at
99.99 %?
Sol’n.
ME = 30 log d (km)
= 30 log 30
= 44.31 dB
In the rheostat method of speed control of dc motor, use of
armature ammeter makes the method _________.
Suitable for rapidly changing load
A single mode stepped index of 25 km length is utilized for
a 1.5 m light source. The spectrum width is 5 nm. Find the
total wavelength dispersion.
The CCITT (ITU-T) TDM (European) system uses added
channel framing to accomplish frame synchronization. If the
number of bits per frame is 256 and the number bits in the
frame code is 8, what is the average number of
synchronization bits needed to acquire frame
synchronization?
For a practice reflex klystron microwave oscillator,
determine the transit time of electron in repeller space in
cycles assuming a mode of 3.
t = Dm 3dB l
= 6.6 ps/nm-km (5 nm) (25 km)
= 825 ps
NOTE:
Dm = dispersion coefficient
= 6.6 ps/nm-km for single mode stepped
index
If the critical coupling is 0.02, what is the bandwidth?
The T-carrier (North American Bell System) uses addeddigit framing to achieve frame synchronization. Determine
the average maximum synchronization time for DS-1 signal
using T1 carrier.
What is the power required for an 8 level code if 10 W is
required for binary code?
In a cellular system, what is the radio capacity using a
frequency reuse ratio of 7 for 600 voice channels.
In radar, what is the Doppler frequency difference with
relative velocity of 2.8 x 108 m/s and transmitting power of
10 GHz?
In the blah coupling, the blah blah chu chu is rotated 35º to
the field. What is the coupling at maximum?
In room acoustics, determine the amount of absorption
contributed at 4000 Hz by 20,000 m3 in air inside concert
halls with relative humidity of air inside is 50%.
CCITT (ITU-R) Rec 930-1 defines the residual bit error
ratio as the error ratio in the absence of fading and …….
What is the RBER of high-grade real circuit with a distance
of 2500 km?
What is the minimum value of PRF to be operated at the
police station to ensure that the blind speed is above 50 m/s?