Description : . If a basic half-wave antenna is mounted vertically, what type of radiation pattern will be produced?
Last Answer : Nondirectional.
Description : What is the radiation pattern of a quarter-wave antenna?
Last Answer : A circular radiation pattern in the horizontal plane, or same as a half wave.
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 is the simplest method of feeding power to the half wave antenna?
Last Answer : To connect one end through a capacitor to the final output stage of the transmitter.
Description : In which plane will the half-wave antenna be operating if it is mounted horizontally?
Last Answer : Vertical plane.
Description : What is included in the total resistance of an antenna system? A. Radiation resistance plus space impedance B. Radiation resistance plus transmission resistance C. Transmission line resistance plus radiation resistance D. Radiation resistance plus ohmic resistance
Last Answer : D. Radiation resistance plus ohmic resistance
Description : Radio wave concentration in the direction of the signal emitted by a directional antenna. A. Back lobe radiation B. Side lobe radiation C. Major lobe radiation D. Transmitted signal
Last Answer : C. Major lobe radiation
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 : Explain half dipole antenna ( Resonant antenna ) with its radiation patteren.
Last Answer : Half wave dipole antenna Explanation: 1. It is a resonant antenna 2. It is exact half wavelength (λ /2) long & open circuited at one end. 3. The dipole antennas have ... pattern is bidirectional. The radiation pattern of half wave dipole antenna is - The radiation pattern
Description : Explain the working of half dipole antenna with its radiation pattern.
Last Answer : Half wave dipole antenna diagram Explanation: 1. It is a resonant antenna 2. It is exact half wavelength (λ /2) long & open circuited at one end. 3. The dipole ... waves exist. Hence radiation pattern is bidirectional. The radiation pattern of half wave dipole antenna is -
Description : A half wavelength Dipole antenna has _________ Radiation Pattern a. Hemispherical b. Omni-Directional c. Isotropic d. End fire
Last Answer : A half wavelength Dipole antenna has Omni-Directional Radiation Pattern
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
Description : An antenna efficiency is computed by using one of the following equations. A. Efficiency = (radiation resistance / transmission resistance) B. Efficiency = (total resistance / radiation resistance) x ... / transmitter output) x 100% D. Efficiency = (radiation resistance / total resistance) x 100%
Last Answer : D. Efficiency = (radiation resistance / total resistance) x 100%
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 : What is meant by the term radiation resistance for an antenna? A. The resistance in the trap coils to received signal B. An equivalent resistance that would dissipate the same amount of power as ... antenna C. The specific impedance of the antenna D. Losses in the antenna elements and feed line
Last Answer : B. An equivalent resistance that would dissipate the same amount of power as that radiated from an antenna
Description : What is meant by the term antenna efficiency? A. Efficiency = effective radiated power/transmitter output x 100% B. Efficiency = radiation resistance/ transmission resistance C. Efficiency = total resistance/radiation resistance x 100% D. Efficiency = radiation resistance/total resistance x 100%
Last Answer : D. Efficiency = radiation resistance/total resistance x 100%
Description : An antenna has a radiation resistance of 72 Ω a loss resistance of 8 Ω and a power gain of 16. Find efficiency and directivity.
Last Answer : An antenna has a radiation resistance of 72 Ω a loss resistance of 8 Ω and a power gain of 16. Find efficiency and directivity.
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 : Where are the current nodes in a half-wave antenna? A. At the ends B. At the center C. Three-quarters of the way from the feed point toward the end D. One-half of the way from the feed point toward the end
Last Answer : A. At the ends
Description : Where are the voltage nodes in a half-wave antenna? A. At the ends B. Three-quarters of the way from the feed point toward the end C. One-half of the way from the feed point toward the end D. At the feed point
Last Answer : D. At the feed point
Description : An antenna with unity gain A. Rhombic B. Half-wave dipole C. Isotropic D. Whip
Last Answer : C. Isotropic
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 : At the ends of a half-wave antenna, what values of current and voltage exist compared to the remainder of the antenna? A. Minimum voltage and minimum current B. Equal voltage and current C. Minimum voltage and maximum current D. Maximum voltage and minimum current.
Last Answer : D. Maximum voltage and minimum current.
Description : Where the voltage node of a half-wave antenna does exists? A. At feed point B. Near the center C. At center D. Near the feed point
Last Answer : A. At feed point
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 product of the power supplied to the antenna and its gain relative to a half-wave dipole in a given direction. A. Peak envelope power B. ERP C. Rated power D. Carrier power’
Last Answer : B. ERP
Description : Unity gain antenna A. Isotropic B. Rhombic C. Half-wave dipole D. Dummy
Last Answer : A. Isotropic
Description : A type of array antenna which consists of one half-wave driven dipole, one reflector and one director A. Hertzian dipole B. Yagi-uda C. Broadside collinear D. Log periodic dipole array
Last Answer : B. Yagi-uda
Description : ECE Board Exam March 1996 The standard reference antenna for the directive gain is ___________. A. elementary doublet B. isotropic antenna C. half-wave dipole D. infinitesimal dipole
Last Answer : B. isotropic antenna
Description : When the polarisation of the receiving antenna is unknown, to ensure that it receives atleast half the power, the transmitted wave should be a) Linearly polarised b) Elliptically polarised c) Circularly polarised d) Normally polarised
Last Answer : c) Circularly polarised
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 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 : For a space wave transmission, the radio horizon distance of a receiving antenna with a height of 64 meters is approximately A. 8 km B. 32 km C. 64 km D. 256 km
Last Answer : B. 32 km
Description : What is the resultant field strength at the receiving antenna in space wave propagation under case 2? A. 0 B. ξd C. 2ξd D. 3ξd
Last Answer : C. 2ξd
Description : A receiver is located 64 km from a space wave transmitting antenna that is 100 meters high. Find the required height of the receiving antenna. A. 36 meters high B. 64 meters high C. 100 meters high D. 182.25 meters high
Last Answer : A. 36 meters high
Description : If a transmitting antenna is 100 meters high and a separate receiving antenna is 64 meters high, what is the maximum space wave communication distance possible between them? A. 18 km B. 72 km C. 164 km D. 656 km
Last Answer : B. 72 km
Description : For a space wave transmission, the radio horizon distance of a transmitting antenna with a height of 100 meters is approximately: A. 10 km B. 40 km C. 100 km D. 400 km
Last Answer : B. 40 km
Description : The number of half-wave patterns in the "b" dimension of rectangular waveguides is indicated by which of the two descriptive subscripts?
Last Answer : Second.
Description : If a half-wave rectifier is added to a half-wave voltage doubler, the resulting circuit is a voltage ___
Last Answer : Trippler.
Description : A half-wave voltage doubler is made up of how many half wave rectifiers?
Last Answer : Two.
Description : Is a full-wave rectifier output easier to filter than that of a half-wave rectifier?
Last Answer : Yes.
Description : If the output of a half-wave rectifier is 50-volts peak, what is the average voltage
Last Answer : 15.9 volts.
Description : What is the output of a half-wave rectifier?
Last Answer : A pulsating dc voltage.
Description : What is the equation for determining average voltage in a half-wave rectifier?
Last Answer : Eavg = 0.318 × Emax
Description : What is the Ripple frequency of a half-wave rectifier if the input frequency is 60 Hz?
Last Answer : 60 hertz.
Description : What terms are often used to describe basic half-wave antennas?
Last Answer : Dipole, doublet and Hertz.
Description : What is the determining factor in classifying whether a radio wave is a ground wave or a space wave?
Last Answer : Whether the component of the wave is travelling along the surface or over the surface of the earth.
Description : Part of a microwave link can be approximated by free space conditions. The antenna gain are each 40 dB, the frequency is 10 GHz, and the path length is 80 km. Calculate the receive power for a transmitted power of 10 W? A. 0.871 μW B. 871 μW C. 0.871 mW D. 871 nW
Last Answer : A. 0.871 μW