Description : Which antenna is not a wideband? A. Discone B. Folded dipole C. Helical D. Marconi
Last Answer : D. Marconi
Description : Which antenna radiates an omnidirectional pattern in the horizontal plane with vertical polarization? A. Marconi antenna B. Discone antenna C. Horn antenna D. Helical antenna
Last Answer : A. Marconi antenna
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 : Whichofthe followingantennasis best excited fromawaveguide? a. Biconical b.Horn c. Helical d. Discone
Last Answer : b.Horn
Description : Whichoneofthe followingterms doesnot applyto theYagi-Uda array? a. Good bandwidth b. Parasitic elements c. Folded dipole d.Highgain
Last Answer : d.Highgain
Description : One ofthe followingis veryuseful as amultibandHFreceivingantenna.Thisisthe: a. conical horn b. folded dipole c. log periodic d. square loop
Last Answer : c. log periodic
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 : Which of the following antennas receives signals equally well from all directions in a horizontal plane? A. Hetz antenna B. Vertical Marconi antenna C. Yagi antenna D. Helical antenna
Last Answer : B. Vertical Marconi antenna
Description : Which antenna is not grounded at one end? A. Hertz B. Marconi C. Dipole D. Whip
Last Answer : C. Dipole
Description : An antenna which is one-tenth wavelength long A. Hertzian dipole B. Loop antenna C. Marconi antenna D. Elementary doublet
Last Answer : D. Elementary doublet
Description : Which antenna is a properly terminated? A. Marconi B. Rhombic C. Dipole D. Yagi-Uda
Last Answer : B. Rhombic
Description : Which is properly terminated antenna? A. Rhombic B. Hertz C. Marconi D. Dipole
Last Answer : A. Rhombic
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 : The input terminal impedance at the center of a folded dipole antenna is A. 72 Ω B. 300 Ω C. 50 Ω D. 73 Ω
Last Answer : B. 300 Ω
Description : Which is a non-resonant antenna? A. Rhombic antenna B. Folded dipole C. End-fire array D. Yagi-Uda antenna
Last Answer : A. Rhombic antenna
Description : What is the input terminal impedance at the center if a folded dipole antenna? A. 300 ohms B. 72 ohms C. 50 ohms D. 450 ohms
Last Answer : A. 300 ohms
Description : Which is the non-resonant antenna? A. Broadside Antenna B. Folded Dipole C. Rhombic antenna D. End fire array
Last Answer : C. Rhombic antenna
Description : Draw the radiation pattern for Dipole antenna: (i) Half wave dipole (ii) Folded dipole.
Last Answer : The radiation pattern for Half wave dipole antenna The radiation pattern for Folded dipole antenna.
Description : What antenna can be used to minimize the effect of Faraday rotation of polarization? A. Dipole B. Parabolic C. Helical D. Rhombic
Last Answer : C. Helical
Description : Type of antenna which is normally used for satellite tracking service. A. Omni B. Helical C. Yagi D. Dipole
Last Answer : B. Helical
Description : Which of the following antennas is best excited from a waveguide? A. Biconical B. Horn C. Helical D. Discone
Last Answer : B. Horn
Description : What is the polarization of a discone antenna? A. Vertical B. Horizontal C. Circular D. Spiral
Last Answer : A. Vertical
Description : The polarization of a discone antenna is _____. A. Horizontal B. Vertical C. Omni D. Directional
Last Answer : B. Vertical
Description : The discone antenna is
Last Answer : useful as a UHF receiving antenna
Description : Anantenna thatis currentlypolarized usthe a. helical b. small circular loop c. parabolic reflector d. Yagi-Uda
Last Answer : a. helical
Description : Helical antennas are oftenused forsatellite trackingatVHFbecauseof a. troposcatter b. superrefraction c. ionospheric refraction d.theFaradayeffect
Last Answer : d.theFaradayeffect
Description : The output waveform produced due to time base generator in a CRO is a) saw tooth b) sinusoidal c) linear d) helical
Last Answer : a) saw tooth
Description : Which has a wider frequency range, a simple dipole or a folded dipole?
Last Answer : Folded dipole.
Description : Band loss is ∙ a. A reduction in transmitter power caused by earth’s surface curvature ∙ b. A reduction in strength of the signal caused by folded dipole bends ∙ c. An attenuation increase caused by bends radiating from the side of the fiber ∙ d. All of these
Last Answer : c. An attenuation increase caused by bends radiating from the side of the fiber
Description : Which antenna does not use the ground? A. Marconi B. Yagi C. Hertz D. Rhombic
Last Answer : B. Yagi
Description : Increasing the resonant frequency of an end-fed Marconi antenna can be done by A. adding a capacitor in series and reducing the physical length B. adding an inductor in series C. adding an inductor in series D. All of these
Last Answer : A. adding a capacitor in series and reducing the physical length
Description : In the case if Marconi antenna, the actual length if the radiating element is A. one-half wavelength B. one-quarter wavelength C. one wavelength D. one-eight wavelength
Last Answer : B. one-quarter wavelength
Description : When a capacitor is connected in series with a Marconi antenna? A. Antenna open circuit stops transmission B. An inductor of equal value must be added C. No change occurs to antenna D. Antenna resonant frequency increases
Last Answer : D. Antenna resonant frequency increases
Description : A theoretical reference antenna that provides a comparison for antenna measurements. A. Marconi antenna B. Isotropic radiator C. Yagi-Uda array D. Whip antenna
Last Answer : B. Isotropic radiator
Description : A shunt-fed quarter-wavelength Marconi antenna A. has maximum RF impedance to ground at its feedpoint B. has a current null at its feedpoint C. has a zero DC resistance to ground D. has zero RF resistance to ground
Last Answer : C. has a zero DC resistance to ground
Description : A one-quarter wavelength shunt-fed vertical Marconi antenna A. has maximum radiation in a vertical direction B. must have a horizontal receiving antenna for the best reception C. must use a receiving antenna for the best reception D. must have a vertical receiving antenna for the best reception
Last Answer : D. must have a vertical receiving antenna for the best reception
Description : The current maximum in a Marconi antenna is found at A. the base of the antenna B. the center of the antenna C. some point between the base and the center of the antenna D. the top of the antenna
Last Answer : A. the base of the antenna
Description : The length of a Marconi antenna to operate with 985 kHz is ______. A. 200 ft B. 500 ft C. 250 ft D. 999 ft
Last Answer : C. 250 ft
Description : Which of the following antennas require good grounding? A. Yagi antenna B. Hertz antenna C. Marconi antenna D. Isotropic antenna
Last Answer : C. Marconi antenna
Description : This is a flexible vertical rod antenna commonly used on mobiles. A. Marconi B. Hertz C. Whip D. Ground plane
Last Answer : C. Whip
Description : ECE Board Exam March 1996 A type of an underground antenna is a/an __________ antenna. A. Hertz B. isotropic C. parabolic D. Marconi
Last Answer : A. Hertz
Description : Indicate which of the following material does not retain magnetism permanently. (a) Soft iron (b) Stainless steel (e) Hardened steel (d) None of the above
Last Answer : (a) Soft iron
Description : indicate the false statement.TheSWRon a transmissionline isinfinity;the line isterminated in a. a short circuit b. acompleximpedance c. an open circuit d. a pure reactance
Last Answer : b. acompleximpedance
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 : Top loadingissometimesusedwithan antenna in ordertoincrease its a. effective height b. bandwidth c. beamwidth d. input capacitance
Last Answer : a. effective height
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 : 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 : 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 : 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