Description : A device that reduces the intensity of light in fiber optics communication systems. A. Reducer B. Quality factor C. Optical attenuator D. Compressor
Last Answer : C. Optical attenuator
Description : Which of the following is used as an optical receiver in fiber optics communications a. APD b. Tunnel diode c. Laser diode d. LED
Last Answer : a. APD
Description : Which of the following is used as an optical receiver in fiber optics communications ∙ a. APD ∙ b. Tunnel diode ∙ c. Laser diode ∙ d. LED
Description : Which of the following is used as an optical transmitter on the Fiber Optical Communications? a. APD b. LSA diode c. PIN diode d. LED
Last Answer : d. LED
Description : A component that samples the microwave signal travelling in one direction down to the transmission line A. Isolator B. Combiner C. Directional coupler D. Attenuator
Last Answer : C. Directional coupler
Description : What is the device used in fiber optic communication which consist of a receiver transmitter use to clean up and amplify digital data moving in one direction and another in the opposite direction? A. Optic compressors B. Optic retarders C. Optic isolator D. Optic regenerators
Last Answer : D. Optic regenerators
Description : The main function of a communications satellite is a/ an A. repeater B. reflector C. beacon D. observation platform
Last Answer : A. repeater
Description : What type of amplifier would be used to amplify the signal from a radio antenna?
Last Answer : An rf voltage amplifier.
Description : A form of regenerative repeater for transmitting signals over a long cable received through a relay in a clearer form. A. Active generator B. Active repeater C. Interpolator D. Audio generator
Last Answer : C. Interpolator
Description : A dielectric waveguide for the propagation of electromagnetic energy at light frequencies a. Stripline b. Microstrip c. Laser beam d. Fiber optics
Last Answer : d. Fiber optics
Description : What is the insertion loss of connector-type splices for a single mode fiber optics? a. 0.51dB b. 0.31dB c. 0.49dB d. 0.38dB
Last Answer : d. 0.38dB
Description : What is the average insertion loss of fusion splice in fiber optics? a. 0.09dB b. 0.9dB c. 0.19dB d. 0.009dB
Last Answer : a. 0.09dB
Description : One of the following is among the types of fiber optics used in electronics communication. A. Step-index multimode B. Graded-index multimode C. Semi-graded multimode D. Single mode
Last Answer : C. Semi-graded multimode
Description : Loss due to the diffraction of light when it strikes on the irregularities formed during the manufacturing process of the fiber optics. A. Absorption loss B. Attenuation C. Bending loss D. Rayleigh scattering loss
Last Answer : D. Rayleigh scattering loss
Description : Designed to receive a signal from a transmitting station on the ground and retransmit it to a receiving station located elsewhere A. Communication satellite B. Repeater C. Relay station D. Transponder
Last Answer : A. Communication satellite
Description : Used to test a fiber optics splice ∙ a. Spectrum analyzer ∙ b. Oscilloscope ∙ c. Optical power meter ∙ d. Field strength meter
Last Answer : c. Optical power meter
Description : ECE Board Exam November 1996 What is the applied power if a thermal RF wattmeter is connected to a transmitter through a variable attenuator? The wattmeter reads 84 mW when 15 dB of attenuation is used. A. 4.656 watts B. 2.656 watts C. 3.656 watts D. 2.856 watts
Last Answer : B. 2.656 watts
Last Answer : A. PAM
Description : Is a non-coherent light source foe optical communications system. a. ILD b. LED c. APD d. PIN Diode
Last Answer : b. LED
Description : A non-coherent light source for optical communications system. A. PIN Diode B. ILD C. APD D. LED
Last Answer : D. LED
Description : In a logic circuit, the NOT gate function _____________. A. does not alter a logical input B. serves to amplify a given signal level C. must be accomplished with a common collector transistor arrangement D. reverses an input logic condition
Last Answer : Answer: D
Description : The common-emitter transistor circuit can amplify a small current signal because a small change in the signal current produces one of the following. Does the change in signal produce a large change in the: w) emitter-base voltage x) base current y) collector current z) collector voltage
Last Answer : ANSWER: Y -- COLLECTOR CURRENT
Description : Fiber optics posses following properties __________ a) Immune electromagnetic interference b) Very less signal attenuation c) Very hard to tap d) All of the mentioned
Last Answer : d) All of the mentioned
Description : Why are visible-light LEDs not used for fiber optics? ∙ a. It has high losses ∙ b. It has short wave ∙ c. It has low attenuation ∙ d. It has weak signal
Last Answer : ∙ a. It has high losses
Description : The most common device used as a light detector in fiber optic communications system. A. LED B. Darlington phototransistor C. APDs D. PIN diode
Last Answer : C. APDs
Description : ECE Board Exam March 1996 It is a spacecraft placed in orbit around the earth carrying onboard microwave receiver and transmitting equipments. A. Fiber optic equipment B. Communications satellite C. Wireless radio system D. Coaxial cable syste
Last Answer : B. Communications satellite
Description : The conversion of the throttle command voltage to the signal necessary to achieve the desired shaft RPM is accomplished by the _____________. A. ahead or astern function generator of the ... circuit C. operational amplifiers in the autorotation circuit D. long time constant amplifier circuit
Last Answer : Answer: A
Description : Noise always affects the signal in a communications systems at the ________. A. transmitter B. channel C. information source D. destination
Last Answer : B. channel
Description : Which of the following is used as an optical transmitter on the Fiber Optical Communications? ∙ a. APD ∙ b. LSA diode ∙ c. PIN diode ∙ d. LED
Description : The most common source of excitation for synchronous motors is a/an _____________. A. low voltage battery B. motor attenuator set C. DC exciter generator D. AC supply
Last Answer : Answer: C
Description : Calculated the noise figure of the amplifier whose Req equals 2518Ω (RT=600Ω) if its driven by a generator whose output impedance is 50Ω. A. 39.4 B. 3.94 C. 394 D. 0.394
Last Answer : A. 39.4
Description : What is a specific path the light takes in an optical fiber corresponding to a certain angle and number of reflection a. Mode b. Grade c. Numerical Aperture d. Dispersion
Last Answer : a. Mode
Description : The bandwidth of optical fiber a. 900MHz b. 900PHz c. 900THz d. 900EHz
Last Answer : c. 900THz
Description : Is the different angle of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitted. a. Acceptance angle b. Modes c. Sensors d. Aperture
Last Answer : b. Modes
Description : The core of an optical fiber has a a. Lower refracted index than air b. Lower refractive index than the cladding c. Higher refractive index than the cladding d. Similar refractive index with the cladding
Last Answer : c. Higher refractive index than the cladding
Description : What is the insertion loss of connector type splices for a single mode optical fiber? A. 0.51 dB B. 0.49 dB C. 0.31 dB D. 0.38 db
Last Answer : D. 0.38 db
Description : What law does a light traveling in air optical fiber follow? A. Millman B. Snell’s C. Maxwell D. Huygen
Last Answer : B. Snell’s
Description : The core of the optical fiber has ______. A. A medium index of refraction B. A lower index of refraction than the cladding C. A lower index of refraction than air D. A higher index of refraction than the cladding
Last Answer : D. A higher index of refraction than the cladding
Description : The different angles of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitter is known as ________. A. refraction B. sensor C. mode D. emitter
Last Answer : C. mode
Description : One of the following is referred to as a major component of an optical time domain reflectometer A. Pulse generator and vertical plate B. Laser and horizontal plate C. Pulse generator laser D. Vertical and horizontal plate
Last Answer : C. Pulse generator laser
Description : Indicate the false statement. Noise figure is defined as A. the ratio of the S/N power supplied at the input terminal of a receiver or amplifier to the S/N power supplied to the output or ... under test, both working at the same temperature over the same bandwidth and fed from the same source
Last Answer : C. an unwanted form of energy tending to interfere with the proper and easy reception and reproduction of wanted signals
Description : What is the reliable measurement for comparing amplifier noise characteristics? A. Thermal agitation noise B. Noise factor C. Noise margin D. Signal-to-noise
Last Answer : B. Noise factor
Description : Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave? A. AF amplifier B. Antenna C. Detector D. Crystal
Last Answer : B. Antenna
Description : Referred to an oscillator signal “leak through” from a properly neutralized amplifier such as a master oscillator power amplifier. A. Carrier B. Stray signal C. Back wave D. Loss wave
Last Answer : C. Back wave
Description : If the percentage modulation of an AM amplifier is 88% and the modulating signal is 1 volt, the carrier has an amplitude of _______________. A. 1.14 volts B. 0.88 volt C. 1.88 volts D. 0.12 volt
Last Answer : A. 1.14 volts
Description : What is meant by antenna gain? A. The final amplifier gain minus the transmission line losses (including any phasing lines present) B. The ratio of the amount of power produced by the antenna ... D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna
Last Answer : D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna
Description : Communications bandwidth that has the highest capacity and is used by microwave, cable and fibre optics lines is known as: (A) hyper-link (B) broadband (C) bus width (D) carrier wave
Last Answer : Answer: B
Description : Essentially a satellite ___________ is a radio repeater in the sky A. transponder B. comparator C. duplexer D. billboard
Last Answer : A. transponder
Description : What is the effective radiated power of a repeater with 200 watts transmitter power output, 4 dB feline loss, 4 dB duplexer and circulator loss, and 10 dB antenna gain? A. 317 W B. 2000 W C. 126 W D. 260 W
Last Answer : A. 317 W
Description : What is the effective radiated power of a repeater with 120 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 6 dB antenna gain? A. 601 W B. 240 W C. 60 W D. 379 W
Last Answer : C. 60 W