Q. The following components are used to measure power output of a 2 kW TWT amplifier

1. TWT
2. Low pass/High pass filter
3. Low power 20 dB attenuator
4. 40 dB directional coupler with matched load
5. Power meter

The correct sequence of connections of these components is:

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Q. The resistance values of a PIN diode under positive bias and negative bias respectively are about

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Q. A PIN diode can be used

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Q. What is the numerical aperture an optical fiber when critical angle is 30°?

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

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Q. In TE₁₀ mode of rectangular waveguide

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Q. Reflection from the object to be measured is significant only when the wavelength is

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Q. The speed at which axial electric field due to signal advances in a TWT is equal to

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Q. Slotted line can be used for measurement of high frequencies

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

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Q. Which of the following lines behaves as infinite line?

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Q. A rectangular waveguide has two stubs each length λ/4 connected at the source end. The stubs are short circuted. Then

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