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

View solution

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

View solution

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

View solution

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

View solution

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

View solution

Q. The duration of sunspot cycle is

View solution

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

View solution

Q. Waveguides are generally used above

View solution

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

View solution

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

View solution

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

View solution

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 __________ .

View solution

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

View solution

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

View solution

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

View solution

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

View solution

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

View solution

Q. A long periodic antenna is a

View solution

Q. The wave in wave guide has

View solution

Q. While determining antenna height for terrestrial microwaves links, the effect of refraction from the atmosphere is taken care of by considering the effective curvature of the earth to be

View solution