Q. A 'rat race' is a

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Q. Compared to coaxial lines, the advantages of wave guides are

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Q. Standard mismatches are used to calibrate SWR and impedance measuring equipments.

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Q. As compared to LED, LASER has

1. higher emission efficiency
2. no tuning arrangement
3. narrow spectral width
4. provision for confinement

Of these statements

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Q. Microwaves are used for

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Q. In a shield helix

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Q. Dielectric constant and conductivity of rocky soil and flat sandy soil are around

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Q. The main advantage of using micro waves for communications is

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Q. A line of length less than λ/4 and open circuited at far end behaves as

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Q. The beam of a radar should be

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Q. TE₁₀ mode of propagation of electromagnetic energy in waveguides can be thought of as

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Q. Consider the following statement:
SWR of a transmission line is infinite when the load is

1. a short circuit
2. a complex impedance
3. an open circuit
4. a pure reactance

Which of the above statements are correct?

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Q. In a reflex klystron the output frequency is determined primarily by resonant frequency of cavity.

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Q. In TE₁₀ mode the largest electric field in a rectangular wave guide, occurs

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Q. Which modes of circular wave guides have circular symmetry?

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Q. In a microwave resistor the wall thickness is made as small as possible to

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Q. In a klystron amplifier the transit time of electron passing the gap in the cavity should be

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Q. In a cable with ∈r = 4, the wave velocity is

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Q. In a backward wave oscillator the efficiency

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Q. Consider the following statements

1. Fading of signals is generally greatest near radio horizon.
2. Fading of signals is generally greatest in shadow zone.
3. Fading is small when a good optical path is present.

Which of the above statements are correct?

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