| 1. | The maximum theoretical output circuit efficiency of a double resonator klystron amplifier is ? | |
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58%
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85%
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25%
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50%
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Report Question| 2. | The frequency of a klystron depends on ? | |
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cavity dimension
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repeller voltage
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distance between two cavities
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dc voltage
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| 3. | The cavity magnetron uses strapping to ? | |
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prevent cathode back heating
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present mode jumping
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improve the phase-focussing effect
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ensure bunching
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| 4. | A magnetic field is used in the cavity magnetron to ? | |
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help in focussing the electron beam, thus prevent spreading
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ensure that the electrons will orbit around the cathode
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prevent anode current in the absence of oscillations
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ensure that the oscillations are pulsed
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| 5. | Which of the following is a microwave power amplifier ? | |
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Travelling wave tube
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Magnetron
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Reflex klystron
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Double cavity klystron
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| 6. | The primary purpose of the helix in a TWT is to ? | |
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reduce the noise figure
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ensure broadband operation
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reduce the axial velocity of the RF field
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prevent the electron beam from spreading in the long tube
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| 7. | Which one of the following is used for its negative characteristic ? | |
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Tunnel diode
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Schottky diode
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Point contact diode
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GASFET
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| 8. | The most power solid state microwave device is ? | |
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MESFET
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repeller voltage
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IMPATT diode
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Gunn diode
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| 9. | Isolator is made up of ? | |
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non-ferrites
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Si
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Ge
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ferrites
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| 10. | In parametric amplifiers used in microwave communication system, pump energy' is the deciding factor for which one of the following ? | |
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Thermal noise level
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Frequency stability
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Maximum output
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Amplification factor
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