Description : Which antenna is not grounded at one end? A. Hertz B. Marconi C. Dipole D. Whip
Last Answer : C. Dipole
Description : In order to get maximum radiation to all surrounding points in the horizontal plane, the antenna used is a A. vertical loop B. vertical quarter-wavelength rod C. array which includes parasitic elements D. a horizontal Hertz dipole
Last Answer : B. vertical quarter-wavelength rod
Description : Which antenna does not use the ground? A. Marconi B. Yagi C. Hertz D. Rhombic
Last Answer : B. Yagi
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 : 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 : 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 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 : Which is properly terminated antenna? A. Rhombic B. Hertz C. Marconi D. Dipole
Last Answer : A. Rhombic
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 : Which of the following antennas receive signals in the horizontal plane equality well from all directions? A. Horizontal Hertz antenna B. Vertical loop antenna C. Vertical Yagi antenna D. A vertical antenna which is a quarter-wavelength long
Last Answer : D. A vertical antenna which is a quarter-wavelength long
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 : 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 : The electromagnetic radiation theory was profounded by A. Sir Edward Appleton B. Guglielmo Marconi C. Heinrich Hertz D. James C. Maxwell
Last Answer : D. James C. Maxwell
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 : Which antenna is not a wideband? A. Discone B. Folded dipole C. Helical D. Marconi
Last Answer : D. Marconi
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 : 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 : 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 : _____ 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 : Which antenna is not properly terminated? A. Resonant B. Non-resonant C. Isotropic D. Whip
Last Answer : A. Resonant
Description : An antenna with unity gain A. Rhombic B. Half-wave dipole C. Isotropic D. Whip
Last Answer : C. Isotropic
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 : Antenna which is not properly terminated A. Isotropic B. Non-resonant C. Whip D. Resonant
Last Answer : D. Resonant
Description : A vertical loop antenna has a A. unidirectional radiation pattern in the horizontal plane B. unidirectional radiation pattern in the vertical plane C. omnidirectional radiation pattern in the horizontal plane D. a bidirectional radiation pattern in the horizontal plane
Last Answer : D. a bidirectional radiation pattern in the horizontal plane
Description : The antenna efficiency of an HF grounded vertical antenna can be made comparable to that of a half-wave antenna A. By installing a good ground radial system B. By isolating the coax shield from ground C. By shortening the vertical D. By lengthening the vertical
Last Answer : A. By installing a good ground radial system
Description : How can the antenna efficiency of an HF grounded vertical antenna be made comparable to that of a half-wave antenna? A. By lengthening the vertical B. By installing a good ground radial system C. By shortening the vertical D. By isolating the coax shield from ground
Last Answer : B. By installing a good ground radial system
Description : The effect of adding parasitic elements of a Hertz dipole is to A. make the antenna more omnidirectional B. reduce its resonant frequency C. increase the antenna’s power gain D. All of these
Last Answer : C. increase the antenna’s power gain
Description : A Hertz antenna is operating on a frequency of 2182 kHz and consists of a horizontal wire that is hanged between two towers. What is the frequency of its third harmonic? A. 727 kHz B. 6546 kHz C. 436 kHz D. 6.546 kHz
Last Answer : B. 6546 kHz
Description : How is it possible to lower the resonant frequency of Hertz dipole antenna? A. By reducing the frequency at the transmitter B. By connecting a capacitor in series with the antenna C. By the connecting a resistor in series with the antenna D. By connecting an inductor in series with the antenna
Last Answer : D. By connecting an inductor in series with the antenna
Description : Where do the maximum current and minimum voltage values on a resonant Hertz dipole exist? A. Center of the antenna B. Near the end of the antenna C. Near the center of the antenna D. Ends of the antenna
Last Answer : A. Center of the antenna
Description : For a shortened vertical antenna, where should a loading coil be placed to minimize losses and produce the most effective performance? A. As low as possible on the vertical radiator B. Near the center of the vertical radiator C. As close to the transmitter as possible D. At a voltage node
Last Answer : B. Near the center of the vertical radiator
Description : In horizontal-dipole antenna, the polarization is A. in the vertical direction B. in the horizontal direction C. circular D. measured at the center of the antenna
Last Answer : B. in the horizontal direction
Description : The advantage of using top loading in a shortened HF vertical antenna is A. lower quality factor B. greater structural strength C. higher losses D. improved radiation efficiency
Last Answer : D. improved radiation efficiency
Description : What antenna radiates equally in all directions? A. Vertical antenna B. isotropic antenna C. Horizontal antenna D. Dipole antenna
Last Answer : B. isotropic antenna
Description : Which does not use vertical polarization antenna? A. AM Broadcasting B. FM Broadcasting C. Mobile Communications D. Satellite Communications
Last Answer : B. FM Broadcasting
Description : What is the polarization of a discone antenna? A. Vertical B. Horizontal C. Circular D. Spiral
Last Answer : A. Vertical
Description : In shipboard satellite dish antennas system, azimuth is referred as the _______. A. 0 to 90 degrees B. Vertical aiming of the antenna C. North to East D. Horizontal aiming of the antenna
Last Answer : D. Horizontal aiming of the antenna
Description : The polarization of a discone antenna is _____. A. Horizontal B. Vertical C. Omni D. Directional
Last Answer : B. Vertical
Description : ______ is an antenna array which is highly directional at right angles to the plane of the array? A. Broadside array B. End-fire array C. Turnstile array D. Log-periodic array
Last Answer : A. Broadside array
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 : 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 : 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 : 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 : What is the maximum line-of-sight distance between a paging antenna 250 ft high and a pager receiver 3.5ft of the ground? A. 25 km B.25mi C. 70.73 km D. 70.73 mi
Last Answer : B.25mi
Description : The electric field lies in a plane parallel to the earth’s surface. A. Elliptical polarization B. Horizontal polarization C. Vertical polarization D. Circular polarization
Last Answer : B. Horizontal polarization
Description : The electric field lines in a plane perpendicular to the earth’s surface. A. Elliptical polarization B. Circular polarization C. Horizontal polarization D. Vertical polarization
Last Answer : D. Vertical polarization