Description : Top loading is used in an antenna in order to increase its ___________. A. input capacitance B. beamwidth C. bandwidth D. effective height
Last Answer : D. effective height
Description : Top loading is used in an antenna in order to increase its ______. A. practical height B. beamwidth C. effective height D. input capacitance
Last Answer : C. effective height
Description : ______ is the measurement of a unilateral antenna properties of directivity A. Phase angle B. Antenna gain C. Beamwidth D. Bandwidth
Last Answer : C. Beamwidth
Description : Zoningis usedwith adielectric antenna inorderto a. reduce the bulk of the lense b. increase the bandwidth of the lens c. increase pin-point focusing d. correct the curvature of the wavefront from a horn that is too short
Last Answer : a. reduce the bulk of the lense
Description : Cassegrain feedis usedwith a parabolic reflectorto a. increase the gain of the system b. increase the beamwidth of the system c. reduce the size of the main reflector d. allowthe feedtobeplacedata convenientpoint
Last Answer : d. allowthe feedtobeplacedata convenientpoint
Description : Which frequency reuse method is less effective because of Faraday’s effect? A. Dual polarization B. Reducing antenna beamwidth C. Zonal rotation D. Spin stabilization
Last Answer : A. Dual polarization
Description : What is the term for the ration of the radiation resistance of an antenna to the total resistance of the system? A. Effective radiated power B. Beamwidth C. Radiation conversion loss D. Antenna efficiency
Last Answer : D. Antenna efficiency
Description : Anungrounded antennanearthe ground a. acts as a single antenna of twice the height b. is unlikely to need a ground screen c. acts as anantennaarray d. must be horizontally polarized
Last Answer : c. acts as anantennaarray
Description : Width measured in degrees of a major lobes between end of the love at which the relative power is one half (-3dB) its value from the peak of the lobe. A. Bandwidth B. Wavelength C. Radiation D. Beamwidth
Last Answer : D. Beamwidth
Description : Is the width of the range of wavelengths emitted by the light source a. Bandwidth b. Chromatic Dispersion c. Spectral width d. Beamwidth
Last Answer : c. Spectral width
Description : The earth area covered by a satellite radio beam. A. Beamwidth B. Bandwidth C. Footprint D. Zone
Last Answer : C. Footprint
Description : Is the width of the range of wavelengths emitted by the light source ∙ a. Bandwidth ∙ b. Chromatic Dispersion ∙ c. Spectral width ∙ d. Beamwidth
Description : .A(75-j50)-is connectedtoa coaxialtransmission lineofZO=75 ,at 10GHz.The bestmethod ofmatching consistsin connecting a. a short-circuited stub at the load b. an inductance at the load c. a capacitance at some specific distance d. a short-circuited stub at some specific distance from the load
Last Answer : d. a short-circuited stub at some specific distance from the load
Description : What is the unit for capacitance ?
Last Answer : Farad
Description : What is capacitance?
Last Answer : Capacitance is the ability of a body to store an electrical charge. Any body or structure that is capable of being charged, either with static electricity or by an electric current exhibits capacitance. C = Q/V where Q is the charge and V is the voltage
Description : _____ is the horizontal pointing angle of an antenna A. Azimuth B. Angle of elevation C. Right angle D. Beamwidth
Last Answer : A. Azimuth
Description : An antenna with very high gain and very narrow beamwidth. A. Helical antenna B. Discone antenna C. Horn antenna D. Parabolic dish antenna
Last Answer : D. Parabolic dish antenna
Description : What happens to the beamwidth of an antenna as the gain is increased? A. The beamwidth increases geometrically as the gain is increased. B. The beamwidth increases arithmetically as the gain is increased ... unaffected by the gain of the antenna. D. The beamwidth decreases as the gain is increased.
Last Answer : D. The beamwidth decreases as the gain is increased.
Description : It is a measure of the microwave power radiated from an antenna as a function of angular direction from the antenna axis. A. Antenna pattern B. Polarization C. Beamwidth D. Sidelobes
Description : Calculate the noise figure of the receiver whose RF amplifier has an input resistance of 1000Ω and an equivalent shot-noise resistance of 2000Ω, a gain of 25 and load resistance of 125 kΩ. Given that the bandwidth is 1. ... to an antenna with an impedance of 75Ω. A. 30.3 B. 3.03 C. 303 D. .303
Last Answer : A. 30.3
Description : If an antenna is too short for the wavelength being used, the effective length can be increased by adding: A. capacitance in series B. inductance in series C. resistance in parallel D. resistance in series
Last Answer : B. inductance in series
Description : Whichoneofthe followingterms doesnot applyto theYagi-Uda array? a. Good bandwidth b. Parasitic elements c. Folded dipole d.Highgain
Last Answer : d.Highgain
Description : The standard reference antenna forthe directive gain isthe a. infinitesimal dipole b. isotropic antenna c. elementary doublet d. half-wave dipole
Last Answer : b. isotropic antenna
Description : Indicatewhich one ofthe followingreasonsforthe use of a groundscreenwith antennasisfalse: a. Impossibility of a good ground connection b. Provision of an earth for the antenna c.Protectionofpersonnelworkingunderneath d. Improvement of the radiation pattern of the antenna
Last Answer : c.Protectionofpersonnelworkingunderneath
Description : Indicate the antenna thatisnotwideband: a. Discone b. Folded Dipole c. Helical d. Marconi
Last Answer : d. Marconi
Description : One ofthe followingis not a reason forthe use of anantenna coupler: a. To make the antenna look resistive b. To provide the output amplifier with the correct load impedance c. To discriminate against harmonics d. To prevent reradiation of the local oscillator
Last Answer : d. To prevent reradiation of the local oscillator
Description : Indicatewhich ofthe followingreasonsfor usinga counterpoisewith antenna isfalse: a. Impossibility of a good ground connection b.Protectionofpersonnelworkingunderground c. Provision of an earth for the antenna d. Rockiness of the ground
Last Answer : b.Protectionofpersonnelworkingunderground
Description : One ofthe followingconsistsof nonresonant antennas: a.The rhombic antenna b. The folded dipole c. The end-fire array d. The broadside array
Last Answer : a.The rhombic antenna
Description : Aship-to-ship communicationssystemisplagued byfading.The bestsolutionseemstobe useof a. a more directional antenna b. a broadband antenna c. frequency diversity d. space diversity
Last Answer : c. frequency diversity
Description : Why ELCB cannot work if Neutral input of ELCB does not connect to ground?
Last Answer : ▪ ELCB is used to detect earth leakage fault. Once the phase and neutral are connected in an ELCB, the current will flow through phase and that same current will have to return neutral so ... that full fault current will come back through ELCB, and there will be no difference in current.
Description : The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be a) 0 b) 1/11 c) 10 d) Infinity
Last Answer : Ans: 1/11
Description : EMDis best describe bywhich statement? a. 70percentofthe corediameter and70%ofthefiberNAshouldbe filled with light b.70 percent of the fiber diameter and 70% of the cone of acceptance should be filled with ... the output d.70 percent of the unwanted wavelengths should be attenuated by the fiber
Last Answer : a. 70percentofthe corediameter and70%ofthefiberNAshouldbe filled with light
Description : The termresponsivityasit appliesto a light detectorisbest described as a. the time required for the signal to go from 10 to 90 percent of maximum amplitude b.the ratio ofthediode output currentto ... of output current to output power d. the ratio of output current to input current
Last Answer : b.the ratio ofthediode output currentto opticalinputpower
Description : The circuit which changes input signal at output with phase shift of 1800 is called (a) Amplifier (b) operational amplifier (c) switch (d) inverter
Last Answer : (d) inverter
Description : Non-inverting amplifier circuits have _______ (a) Very high input impedance (b) very low input impedance (c) low output impedance (d) none of above
Last Answer : (a) Very high input impedance
Description : The product of antenna input power and the antenna power gain expressed in kW is called __. A. Effective Radiated Power (ERP) B. Effective Isotropic Radiated Power (EIRP) C. Radiated Power D. Transmit Power
Last Answer : A. Effective Radiated Power (ERP)
Description : The antenna effective height is ____ to ____ of the actual height. A. ½ to 2/3 B. ½ to ¾ C. ¼ to 2/3 D. ¼ to ¾
Last Answer : A. ½ to 2/3
Description : If the length of a Hertz dipole is decreased A. its resonant frequency will be lowered its distributed inductance will be increased B. its distributed inductance will be decreased C. its ... frequency will be increased D. its distributed capacitance between the antenna and ground will be increased.
Last Answer : C. its resonant frequency will be increased
Description : A transmitted signal 5 meters in wavelength is received by an antenna coil having a 50-Ω resistance and a 0.01 H inductance. What is the capacitance of the tuner shunting the antenna coil at this point? A. 0.704 fF B. 0.704 μF C. 0.704 nF D. 0.704 mF
Last Answer : A. 0.704 fF
Description : What happens to the bandwidth of an antenna as it is shortened through the use of loading coils? A. It is increased B. It is decreased C. No change occurs D. It becomes flat
Last Answer : A. It is increased
Description : What is antenna bandwidth? A. Antenna length divided by the number of elements B. The angle between the half-power radiation points C. The angle formed between two imaginary lines drawn through D. The frequency range over which an antenna can be expected to operate satisfactorily
Last Answer : D. The frequency range over which an antenna can be expected to operate satisfactorily
Description : What is meant by the term antenna bandwidth A. Antenna length divided by the number of elements. B. The angle between the half-power radiation points C. The frequency range over which and antenna ... perform well D. The angle formed between two imaginary line drawn through the ends of the elements
Last Answer : C. The frequency range over which and antenna can be expected to perform well
Description : A helical antenna is used for satellite tracking because of ______. A. Broad bandwidth B. Good front-to-back C. Maneuverability D. Circular polarization
Last Answer : D. Circular polarization
Description : _______ is the horizontal pointing angle of an antenna. A. Right angle B. Angle of elevation C. Bandwidth D. Azimuth
Last Answer : D. Azimuth
Description : Define each of following terms of operational amplifiers i) Slew rate ii) Input offset voltage iii) Voltage gain iv) Input capacitance
Last Answer : i) Slew rate:- Maximum rate of change of o/p voltage per unit of time. It is express in volt/µsec. ii) Input offset voltage:- The voltage that must be applied between two ... capacitance that can be measured at either be inverting or non-inverting terminal with other terminal connected to ground.
Description : Comment on the effect of negative feedback on the gain, input and output resistance of the feedback amplifiers.Describe the gain bandwidth product term used in this context and its importance.
Last Answer : Effect of negative feedback: 1. Gain decreases with negative feedback. 2. Input resistance increases with negative feedback. 3. Output resistance decreases with negative feedback. Explanation ... feedback bandwidth increases which means it is stable output on more range of frequency.
Description : _____ is the angle between the half-power radiation points A. Critical angle B. Beamwidth C. Angle of elevation D. Azimuth
Last Answer : B. Beamwidth
Description : Comparing the signal strength arriving at the driven element from the desired direction to the signal strength reaching the driver from the opposite direction. A. Directivity B. Sensitivity C. Beamwidth D. Front-to-back ratio
Last Answer : D. Front-to-back ratio
Description : The radiation patterns of earth coverage antennas have a beamwidth of approxiamately A. 21˚ B. 5˚ C. 17˚ D. 35˚
Last Answer : C. 17˚
Description : What is caused by the transverse nature of electromagnetic waves? A. Polarization B. Interference C. Beamwidth D. Gain
Last Answer : A. Polarization