| 1. | A cavity is a ? | |
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band-pass filter
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low-pass filter
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band-stop filter
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high-pass filter
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Report Question| 2. | For some applications, circular waveguides may be preferred to rectangular waveguides because of ? | |
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the smaller cross-section needed at any frequency
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rotation of polarisation
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lower attenuation
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freedom from spurious modes
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| 3. | The waveguide (a=1.5 cm, b=1 cm) is loaded with a dielectric (Er=4). Which one of the following is correct? The 8 GHz signal will ? | |
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be absorbed in the guide
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pass through the waveguide
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not pass through the waveguide
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none of the above
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| 4. | Following mode exists in rectangular waveguide supporting TM mode ? | |
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TM21
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TM04
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TM
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TM30
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| 5. | Inside a waveguide with perfectly conducting walls, any current present is in the form of ? | |
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conduction current only
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displacement current only
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sometimes displacement current and sometimes conduction
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partially displacement current and partially conduction
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| 6. | In a waveguide, the evanescent modes are said to occur if ? | |
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the propagation constant is imaginary
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the signal has a constant frequency
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the propagation constant is real
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only the TEM waves propagate
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| 7. | Assuming perfect conductors of a transmission line TEM propagation is NOT possible in ? | |
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parallel twin-wire line in air
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coaxial cable
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semi-infinite parallel plate waveguide
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air-filled cylindrical waveguide
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| 8. | Usually, microwave signals are not used for ionospheric propagation. The reason is ? | |
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scattering prevents propagation of microwaves through ionosphere
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microwaves penetrate through ionospheric layers
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drastic dispersion takes place for microwave signals in ionosphere
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ionospheric layers absorb microwaves tremendously
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| 9. | High frequency waves are ? | |
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affected by solar cycle
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absorbed by F, layer
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reflected by D layer
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None of the above
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| 10. | The correct sequence of subsystems of Klystron amplifier as they appear in the direction of flow of the electron beam is ? | |
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Cathode, Buncher cavity, Catcher cavity, Collector
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Cathode, Buncher cavity, Collector, Catcher cavity
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Buncher cavity, Cathode, Catcher cavity, Collector
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Buncher cavity, Cathode, Collector, Catcher cavity
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