58801. If a and b are the dimensions of waveguide then
58802. The frequency range for satellite communication is
58803. A λ/8 section of transmission line is determined of load impedance of (2 - j 5) Ω. If characteristic impedance of line is 10 Ω. Then input impedance of line is
58804. Long distance short wave radio broadcasting based on
58805. Many circles are drawn in a Smith chart used for transmission line calculations. The circle shown in the figure represents
58806. A loop antenna is a commonly used for
58807. For transmission line load matching over a range of frequencies, it is best to use a
58808. Whenever a wave is incident on a perfect conductor then the reflection coefficient is
58809. Which one set of the following Maxwell's equation gives the basic idea of radiation ?
58810. When a wave is incident from the more dense into a less dense medium at an angle equal to or exceeding the critical angle, the wave suffers total internal __________ .
58811. Power gain and directivity related with, Gp power gain, Gd directive gain
58812. Radiation intensity in a given direction is the
58813. The capacitance between two spheres, whose separation is very much larger than their radii R, is given approximately as
58814. If ωε is the displacement current factor and s is conduction current density factor then which of the following statements is incorrect?
58815. Parabolic and lens antenna used at
58816. Which of the following statement regarding waveguides is incorrect?
58817. The potential that appears at a point in space due to the current which caused it is called potential
58818. It is desired to reduce the reflection at an air porcelain by use of 7/4 plate (for Porcelain μ = 40, and εr = 7). The thickness of the polystyrene plate required at 10 GHz will be
58819. Root developed from?
58820. The useful magnetic flux obtainable from any closed surface is
58821. The voltage and current distributions on a grounded λ/4 dipole (Marconi antenna) are similar to those of a half wave dipole in space.
58822. The equation ∇ . J = 0 is called
58823. It is best to use for coupling a coaxial line to a parallel wire transmission line.
58824. In H-plane metal plate lens the travelling wave front is
58825. MUF is depend upon
58826. In case of antenna the ratio of the power radiated in the desired direction to the power radiated in the opposite direction is known as
58827. Which of the following is not between F2 layer and D layer?
58828. The radiation pattern of Hertzian dipole in the plane perpendicular to dipole is a
58829. The transmitting antennas for lower frequencies (below 500 kHz) are generally
58830. In an home T.V. receiver, the leed in from the antenna is
58831. A satellite that simply reflect back the signals from one region of the earth to the other region is known as
58832. Conductivity is measured in terms of
58833. The critical frequency of 'F' layer is greater than 30 MHz.
58834. Crushing strength of a good building stones should be more than
58835. Which of the following will increase the antenna radiation efficiency?
58836. A waveguide operated below cut off frequency can be used as
58837. A time varying field is applied to a circuit with a capacitor- which of the following statements is correct?
58838. Which of the following impedance inversion is obtained?
58839. In case of surface waves the field strength at a point is directly proportional to
58840. The percentage of Alumina in good brick earth lies between
58841. ZL = 200 Ω and it is desired that Zi = 50 Ω The quarter wave transformer should have a characteristic impedance of
58842. A broadside array consisting of 200 cm wavelength with 10 half-wave dipole spacing 10 cm. And if each array element feeding with 1 amp. current and operating at same frequency then find the half power beamwidth
58843. Refractive index of glass is 1.5. Find the wavelength of a beam of light with a frequency of 1014 Hz in glass. Assume velocity of light is 3 x 108 m/sec in vacuum.
58844. The function f(x - vot) represent which of the following?
58845. A broadside array operating at 100 cm wavelength consist of 4 half-wave dipoles spaced 50 cm apart. Each element carries radio frequency current in the same phase and of magnitude 0.5 A. The radiated power will be
58846. Le Chatelier’s test is used to determine the
58847. Basic purpose of retarder in concrete is
58848. Theodolite is an instrument used for
58849. The process of turning the telescope about the vertical axis in horizontal plane is called
58850. Scale on which three dimensions can be measured called