Communications Engineering Coaching Materials: Section 3 Module 8

(Last Updated On: December 8, 2017)

This is the Section 3 Module 8 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 3 Module 8

· Octet Rule

Ans: ATM

· Replace LO

Ans: Frequency Synthesizer

· Trunk circuit; if VNL exceeds 2.5 dB

Ans: Echo suppressor

· Unsolicited messages

Ans: Push messages

· Brief messages

Ans: SMS

· EDGE modulation technique

Ans: 8-PSK

· DWDM

Ans: Dense wave division multiplexing

· Launched at a speed more than 25000 m/s

Ans: Space probe

· Must not have interference

Ans: First zone

· Electro-optical modulation

Ans: Electro-optical effect

· Radius of earth, point of observer

Ans: Nadir

· Tuning

Ans: Oscillator, Driver and PA

· Threaded metal in absence of Transmission line

Ans: Tuning screw

· Attractive

Ans: Modem pool

· Distance between microphone and lips

Ans: 2 inches

· Chip – Bit

Ans: pseudorandom code

· Shape of 100% modulation of trapezoid

Ans: Triangular

· Unique paging address

Ans: Capcode

· IBM token ring

Ans: 260 nodes

· Token ring

Ans: 4 to 16 Mbps

· Pulses in optical fiber does not disperse

Ans: Soliton

· Hard tubing used in low microwave frequencies

Ans: Hard wire

· Dielectric constant of 2.27 , used in cables for insulation

Ans: Polyethylene

· Increase by 3G capacity

Ans: 70%

· For a specific area

Ans: Despun

· Encryption

Ans: Public Key

· Decipher

Ans: Private Key

· Number on mobile phone

Ans: Numeric Assignment Module NAM

· Antenna / tower height

Ans: 60 ft above the ground / 20 ft above the building

· RF

Ans: Howl

· GEO satellite

Ans: 6879 statute mile/hr

· Forward and reverse frequency diff

Ans: 45 MHz

· Using other mobile serial number to make calls

Ans: Clone Fraud

· Interconnection between MSC and PSTN

Ans: Back Haul

· Tonal ratio octave

Ans: 2:1

· Radio blackout occasional

Ans: R1

· Radio blackout for tens of minutes

Ans: R2

· Radio blackout for one hour

Ans: R3

· Radio blackout for one to two hours

Ans: R4

· Radio blackout for a number of hours

Ans: R5

· Largest network of satellite for ships, aviation, etc – 21 satellites

Ans: Intelsat

· Angle of reflection

Ans: critical angle along the normal

· Horizontal scanning lines for HDTV

Ans: 1125 lines

· Changes made on a client server cannot be known to other users

Ans: Record locking

· Purity

Ans: Q, I

· Continuous squelch

Ans: Squelch circuit

· Advantage of using FOC

Ans: Unlimited Bandiwdth

· High Z

Ans: Electret, condenser, crystal

· Low Z

Ans: Ribbon, dynamic, carbon

· Unsolicited messages

Ans: Spam

· Unsubscribe

Ans: Opt out

· In the list

Ans: Opt in

· 80% humidity

Ans: 16.4×10-3

· 2 line to 4 wire

Ans: Hybrid Transformer

· Remove spurious

Ans: Spectral purity

· Need high superbands

Ans: 6 dB or better

· Sub & 10 bands

Ans: 5 dB or better

· Evolution of coax

Ans: Strip line

· Top strip

Ans: Microstrip

· 33.6 facsimile

Ans: V.32 bis

· circuits family that cannot be interchanged

Ans: V.24

· RS232C

Ans: 50 ft

· 10BaseT

Ans: 100m

· D-AMPS

Ans: IS-136

· CDMA

Ans: IS-95

· Disadvantages of grid to plate

Ans: low efficiency, hard to adjust

· Advantage of grid to plate

Ans: Low AF

· Speech coding D-AMPS

Ans: VSLEP

· Speech coding GSM

Ans: RPE-LPc

· Random 1 & 0

Ans: Pseudorandom code

· Bipolar violation

Ans: 2 consecutive logic 1 with same polarity

· 1st fax sold, Giovanni Caselli

Ans: Pantelegraph

· GASFET

Ans: PARAMP

· not peer to peer

Ans: MS Office 2000

· Least expensive

Ans: F type connector

· Most expensive

Ans: N type connector

· Millimeter waves

Ans: Above 300 GHz

· Fraudulent

Ans: MIN and ESN

· Protect the personnel

Ans: Interlock

· Real time

Ans: Circuit switch

· Real time

Ans: Frequency and space

· Freq hopping

Ans: interchanging frequency

· Chroma crosstalk

Ans: Comb filter

· Gas in a tube

Ans: Blue haze

· Contrast

Ans: Y video

· Phase angle

Ans: Tint

· Crosstalk of KTS, PBX

Ans: the same

· Thickness

Ans: gunn diode

· Keyspeed – BW

Ans: proportional

· Submarine

Ans: fiber optic

· multimode

Ans: greater numerical aperture, greater core diameter

· Base station

Ans: $ 0.5 M – 0.75 M

· Improved CDMA

Ans: CDMA2000

· Higher antenna height

Ans: less refractive index

· Coax

Ans: 0.5 – 0.9

· Connect directly computers

Ans: Crossover

· Transmission of many channel

Ans: Cross color

· Affected when loss of picture

Ans: Loss of sound

· LEO advantage

Ans: shorter distance

· Glonass inclination

Ans: 64.8°

· GPS separation

Ans: 60°

· Isolation, amplifier

Ans: Buffer

· 56 kbps

Ans: V.90

· Velocity of sound in wood

Ans: 3300 m/s

· CATV1

Ans: 1%

· Limiter, radio detector

Ans: Foster Seeley

· Transmission of bits

Ans: Physical layer

· Routing

Ans: Network Layer

· Antenna stacking

Ans: increase horizontal, Decrease vertical

· How repeaters are identified

Ans: Automatic ID, code, voice

· Volume reverberation chamber method

Ans: 200 m3

· Threshold

Ans: 10-12 W/m2

· Area

Ans: 10 & 12 m2

· Best frequency range of human hearing

Ans: 1 – 4 kHz

· Cinema volume of person

Ans: 3.1

· Church volume of person

Ans: 7.1 – 9.9

· Free running

Ans: VCO

· WiMAX

Ans: 3 to 5 miles

· MPEG 7

Ans: Multimedia Content Description Interface

· OMEGA

Ans: 88% – 98% accuracy

· Emission at BW

Ans: 99%

· GLONASS inclination with ref to the equator

Ans: 64.8°

· FDM Telephony

Ans: SSBSC AM

· Person has cellular phone in 2001

Ans: 1 out of 7

· FM carrier subcarrier

Ans: L-R FM stereo

· Submarine and aeronautical

Ans: L-band

· Increase signal power level

Ans: Class C amplifier

· Peak white

Ans: highest luminance

· CATV satisfaction

Ans: 60 dB

· Subdiscipline of acoustics; use if hydrophone, loudspeaker, etc..

Ans: Transduction loss

· Not an acoustic defect

Ans: Reverberation

· Carrier transmitted

Ans: Balanced modulator is not properly balanced

· Shift register

Ans: bit splitter

· TACAN

Ans: 960 – 1215 MHz

· Correct syllables

Ans: Articulation efficiency

· Intelligibility

Ans: Articulation test

· Full duplex

Ans: Not enabled with enabled echo suppressor

· Wave guide not used in low frequency because of

Ans: large cross sectional area

· Monitors on board condition

Ans: TTC

· SONET

Ans: handle large BW

· CPE

Ans: customer premises equipment

· NRFAT

Ans: 1880 – 1900 MHz

· Coax velocity factor

Ans: 0.6 to 0.8

· Combine local oscillator and mixer

Ans: Autodyne receiver

· Set original frequency before modulation

Ans: TRF

· IMTS

Ans: Improved Mobile Telephone Service

· UMTS

Ans: Universal Mobile Telecommunications System

· Radials

Ans: Counterpoise

· Antenna counterpoise

Ans: Less capacitance

· B- Channel

Ans: ISDN 4.8 – 64 kbps

· Longer distance in LANS

Ans: Fiber optic

· Klystron

Ans: 10 MW ; 70 dB

· Pre –emphasis

Ans: boost high frequency

· study of radar

Ans: Christian Hulsmayer

· GLONASS

Ans: 11 hrs and 15 minutes to complete orbit

· LORAN C/D

Ans: 100 kHz center frequency

· Payload pointer

Ans: SONET

· 1300nm, multimode

Ans: Least attenuation fiber

· 4M / MHz

Ans: 100,000 subscribers

· Paired – 5-10 MHz

Ans: P8M

· Unpaired – 5-10 MHz

Ans: P6M / MHz

· Paired – 10-15 MHz

Ans: P10M /MHz

· Unpaired -10-15 MHz

Ans: P8M / MHz

· Paired – less than 5 MHz

Ans: P5M / MHz

· Unpaired – less than 5 MHz

Ans: P3M / MHz

· Paired – above 15 MHz

Ans: P15M / MHz

· Unpaired – above 15 MHz

Ans: P12M / MHz

Complete List of Communications Engineering Coaching Materials