62751. As wavelength decrease the size of high directivity antenna
62752. Which of the following modes of transmission will not be supported by a rectangular waveguide?
62753. In a circular waveguide with radius r, the dominant mode is
62754. Who is the journalist associated with “Kesari”?
62755. A parametric amplifier uses
62756. Assertion (A): Impatt diode can be used in both amplifiers and oscillators.Reason (R): Impatt diode has a low resistance.
62757. Which one of the following can be used for amplification of microwave energy?
62758. Who among the following has been elected in the International Tennis Hall of Fame?
62759. At frequencies of 10 MHz and higher the impedance represented by ground is primarity
62760. A disadvantage of microstrip line as the connections of compared to strip line is that former
62761. As frequency increases, the transmission efficiency
62762. A circular polarizer converts a linearly polarized wave into a circularly polarised wave.
62763. If D is diameter of circular waveguide the cutoff wave-length for TE11 mode is equal to
62764. The external magnetic field in a magnetron is such that lines are
62765. Varactor diodes use
62766. A circular waveguide carries TE11 mode whole radial electric field is given by
Er = E0j1(r) sin Φ V/m
where r is radial distance in cm from the axis
The cut off wavelength is
62767. Assertion (A): Impatt diode is an avalanche diode.Reason (R): Avalanche breakdown phenomenon occurs when a p-n junction is reverse biased.
62768. A radar has a maximum range of 120 km. The maximum allowable pulse repetition frequency for unambiguous reception is
62769. In a line with finite attenuation
62770. In the given figure a short circuited transmission line resonator If n = 1, 2, 3...
62771. The electric field in a TWT due to applied signal
62772. In 8 cavity magnetron the p mode corresponds to a total phase shift equal to
62773. Satellite communication systems use the frequency band
62774. The characteristic impedance of a cable is about
62775. The Q factor of a waveguide resonator is given by (ω0 is resonant frequency, U is energy storage and WL is the power loss)
62776. A TR (transmitter receiver) tube has
62777. When duct propagation exists
62778. The substance that contains the maximum amount of nitrogen is?
62779. Of my three daughters she is ..........?
62780. If in line the characteristic impedance becomes real.
62781. In a microwave coaxial cable the inner conductor radius is a and inner radius of outside conductor is b. For TE11 mode the cut off wavelength is about
62782. In a magnetron the magnetic flux density is of the order of
62783. For a directional coupler the power is in the ratio of
62784. As regards rectangular and circular waveguides
62785. In a high frequency coaxial line and the length of line characteristic impedance is a function of
62786. Assertion (A): In TE10 mode the cutoff frequency of rectangular waveguide is where a is the broad dimension and c is velocity of light.Reason (R): TE10 mode is the dominant mode in rectangular waveguide.
62787. The usable bandwidth of ridge wave guide
62788. Assertion (A): In TE mode for rectangular waveguide.Reason (R): In TM mode for rectangular waveguide.
62789. The attenuation characteristics of a loaded line is similar to that of
62790. A microstrip line has ∈r = 9. The normalised wavelength is about
62791. If the repeller voltage in a klystron oscillator is increased the transit time of electron
62792. In which of the following devices can the operation be visualised in terms of a series feedback loops?
62793. The first and second subscripts in models of circular waveguides depict
62794. In which mode of circular waveguide does the attenuation continuously decrease as frequency is increased?
62795. In which mode of rectangular waveguide are all field components zero?
62796. A microstrip line has dielectric having relative permittivity ∈r. The effective dielectric constant is
62797. The rotation of direction of E field of a linearly polarized wave passing through a magnetised ferric medium is called
62798. If air pressure in a rectangular waveguide is increased the maximum power handling capacity
62799. A directional coupler is used to determine
62800. A square waveguide carries TE11 mode whose axial magnetic field is given by Hz = H0 , where the guide dimensions are in cms. The cut off frequency of the mode is