Description : Earth station uses what type of antenna A. Despun antenna B. Helical antenna C. Toroidal antenna D. Cassegrain antenna
Last Answer : D. Cassegrain 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 : _____ is an antenna with a number of half-wave antenna on it. A. Antenna array B. Tower C. Omni-directional D. Rhombic
Last Answer : A. Antenna array
Description : ECE Board Exam March 1996 An antenna which is not resonant at a particular frequencies and so can be used over a wide band of frequencies and so can be used over a wide band of frequencies is called A. aperiodic B. boresight C. cassegrain D. top-loaded
Last Answer : A. aperiodic
Description : Which antenna does not use the ground? A. Marconi B. Yagi C. Hertz D. Rhombic
Last Answer : B. Yagi
Description : The rhombic antenna is primarily used for A. ground wave propagation B. space wave propagation C. ionosphere scatter propagation D. sky wave propagation
Last Answer : D. sky wave propagation
Description : An antenna with unity gain A. Rhombic B. Half-wave dipole C. Isotropic D. Whip
Last Answer : C. Isotropic
Description : Which antenna is a properly terminated? A. Marconi B. Rhombic C. Dipole D. Yagi-Uda
Last Answer : B. Rhombic
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 : The typical length of the rhombic antenna is ____. A. 2λ to 8λ B. 10λ to 20λ C. 1λ to 3λ D. 5λ to 10λ
Last Answer : A. 2λ to 8λ
Description : What is the typical gain of a rhombic antenna? A. Between 15 to 60 B. Between 20 to 90 C. Between 50 to 75 D. Between 10 to 25
Last Answer : A. Between 15 to 60
Description : Refers to a type of beam antenna which uses two or more straight elements arranged in line with each other. A. Dipole antenna B. Yagi antenna C. Whip antenna D. Rhombic antenna
Last Answer : B. Yagi antenna
Description : Unity gain antenna A. Isotropic B. Rhombic C. Half-wave dipole D. Dummy
Last Answer : A. Isotropic
Description : Which is properly terminated antenna? A. Rhombic B. Hertz C. Marconi D. Dipole
Last Answer : A. Rhombic
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 : Which antenna is not a wideband? A. Discone B. Folded dipole C. Helical D. Marconi
Last Answer : D. Marconi
Description : What is the gain, in dB of a helical antenna with diameter of λ/3, 10 turns at pitch of λ/4, used at 100 MHz? A. 16 B. 41.1 C. 31.4 D. 1.25
Last Answer : A. 16
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 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 : Collects very weak signals from a broadcast satellite A. Helical antenna B. Satellite dish C. LNA D. TWT
Last Answer : B. Satellite dish
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 : Type of antenna which is normally used for satellite tracking service. A. Omni B. Helical C. Yagi D. Dipole
Last Answer : B. Helical
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 : Horn-Fed Cassegrain reflector antenna
Last Answer : Design Horn-Fed Cassegrain reflector antenna for operating frequency, gain, beam width, dish ... Provide proper citations and references in write-up
Description : What is the main disadvantage of the rhombic antenna?
Last Answer : It requires a large antenna site.
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 : _____ is an antenna made up of a number of full wavelengths A. Elementary doublet B. Log-periodic C. Long wire D. Whip
Last Answer : C. Long wire
Description : _____ of an antenna is a measure of how the antenna concentrates its radiated power in a given direction. A. Efficiency B. Power C. Gain D. Polarization
Last Answer : C. Gain
Description : If 4 kW in antenna produces 50 μV/m in a receiving antenna, a 15 kW will produce _____. A. 200 μV/m B. 10 μV/m C. 100 μV/m D. 20 μV/m
Last Answer : C. 100 μV/m
Description : The antenna radiates _____ polarized waves when the transmitter antenna is horizontally installed. A. Vertically B. negatively C. horizontally D. circularly
Last Answer : C. horizontally
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 : A horizontal antenna is _____. A. vertically polarized B. horizontally polarized C. centrally polarized D. circularly polarized
Last Answer : B. horizontally polarized
Description : The polarization of a discone antenna is _____. A. Horizontal B. Vertical C. Omni D. Directional
Last Answer : B. Vertical
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 : The first laser emitted a. Pulses of 694 nm red light b. A continuous red beam c. Pulses of white light from a helical flashlamp d. Spontaneous emission
Last Answer : a. Pulses of 694 nm red light
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 : ECE Board Exam March 1996 An antenna that is circularly polarized is the ____________. A. parabolic reflector B. helical C. Yagi-uda D. small circular loop
Last Answer : B. helical
Description : Indicate the antenna thatisnotwideband: a. Discone b. Folded Dipole c. Helical d. Marconi
Last Answer : d. Marconi
Last Answer : A helical antenna is used for satellite tracking because of its Circular polarization
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 : Open channel liquid flow is most conveniently measured by a (A) Hot wire anemometer (B) Notch (C) Rotameter (D) Segmental orifice
Last Answer : (B) Notch
Description : Which antenna is not grounded at one end? A. Hertz B. Marconi C. Dipole D. Whip
Last Answer : C. Dipole
Description : Which one is an antenna coupling unit? A. Coupler B. Diplexer C. Lecher wire D. Duplexer
Last Answer : B. Diplexer
Description : One of the following makes an antenna physically long but electrically short A. Adding L in series B. Adding C in series C. Top loading D. Both A and C
Last Answer : B. Adding C in series
Description : One of the following is not a reason for the use of an earth mat A. impossibility of a good ground connection B. provision of an earth for the antenna C. protection of personnel working underneath D. improvement of the radiation pattern of the antenna
Last Answer : C. protection of personnel working underneath
Description : Not a reason for the use of an antenna 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 re-radiation of the local oscillator
Last Answer : D. To prevent re-radiation of the local oscillator
Description : Indicate which of the following reasons for using metal counterpoise with antennas is false. A. Impossibly of a good ground connection B. Protection of personnel working underneath C. Provision of an earth for the antenna D. Rockiness of the ground itself
Last Answer : B. Protection of personnel working underneath
Description : One of the following is very useful as a multiband HF receiving antenna. A. Parabolic antenna B. Elementary doublet C. Log-periodic D. Square loop
Last Answer : C. Log-periodic
Description : An ungrounded antenna near the ground A. acts as a single antenna of twice the height B. is unlikely to need an earth mat C. acts as antenna array D. must be horizontally polarized
Last Answer : C. acts as antenna array
Description : Factors that determine the radiation resistance of an antenna A. Transmission line length and height of antenna B. The location of the antenna with respect to nearby objects C. It is a constant for all antennas since it is physical D. Sunspot activity and the time of day
Last Answer : B. The location of the antenna with respect to nearby objects