Q. UHF and microwaves in the frequency range 300 MHz to 30 GHz can be best transmitted using __________ propagation

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Q. The directive gain of λ/2 resonant wire is 1.64.

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Q. The effective height of a vertical radiator can be increased by

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Q. When an electromagnetic wave travelling in one medium strikes upon a second medium (having a different conductivity) the wave will be

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Q. The line of sight communication requires that transmit and receive antennas to face each other. If the transmit antenna is vertically polarized, for the best reception the receive antenna should be

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Q. An antenna has 40 Ω resistance and 60 Ω radiation resistance. The efficiency of the antenna is

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Q. The duration of sunspot cycle is

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Q. Electromagnetic cavity resonators (energy storage devices) are used in

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Q. Waveguides are generally used above

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Q. Which type of fading causes serious distortion of modulated signal?

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Q. Which of the following is abnormal variation in ionosphere?

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Q. Troposphere is the upper part of the Earth's atmosphere which absorbs large quantities of Sun's radiations.

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Q. For resonant long wire antenna 'n' half wavelength long in free space, if 'n' is increased then inclination of the major lobe with wire axis will __________ .

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Q. The maximum effective aperture of λ/2 (half-wave) antenna is

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Q. Microwave signals follow the curvature of the earth and the phenomenon is known as

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Q. In a carbon-zinc cell the function of the depolarizer is that

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Q. Induction and radiation fields are equal at a distance equal to

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Q. The effective height of an antenna is slightly greater than physical height because

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Q. A long periodic antenna is a

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Q. The wave in wave guide has

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