Q. In a circular waveguide with radius r, the dominant mode is

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Q. If 'a' is the width of rectangular wave guide and 'λ' is the wave length, then

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Q. A parametric amplifier uses

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Q. Assertion (A): Impatt diode can be used in both amplifiers and oscillators.

Reason (R): Impatt diode has a low resistance.

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Q. Which one of the following can be used for amplification of microwave energy?

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Q. At frequencies of 10 MHz and higher the impedance represented by ground is primarity

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Q. A disadvantage of microstrip line as the connections of compared to strip line is that former

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Q. As frequency increases, the transmission efficiency

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Q. A circular polarizer converts a linearly polarized wave into a circularly polarised wave.

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Q. If D is diameter of circular waveguide the cutoff wave-length for TE₁₁ mode is equal to

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Q. The external magnetic field in a magnetron is such that lines are

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Q. Varactor diodes use

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Q. 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

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Q. The domain mode in rectangular waveguide is

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Q. The reverse voltage applied to a varactor diode

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Q. To ensure that only dominant mode TE₁₀ is allowed to propagate in an air filled rectangular waveguide, the lower frequency limit and upper frequency limit are

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Q. The skin depth at 1000 MHz as compared to that at 500 MHz is

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Q. The transit time (in cycles) for electrons in repeller space of reflex klystron oscillator for sustaining oscillations is (n is any integer)

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Q. In a TWT the amplitude of resultant wave travelling down the helix remains constant

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Q. In an infinite line the input impedance at every point is equal to characteristic impedance.

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