| 1. | The purpose of a Cass grain feed in a parabolic reflector antenna is to ? | |
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Achieve higher antenna gain
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Reduce the antenna size
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Reduce the beam width
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Ease of locating the feed at convenient point
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Report Question| 2. | In a super heterodyne receiver, rejection of the image signal can be achieved by using a ? | |
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Higher local oscillator frequency
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Crystal oscillator
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Narrow band pass filter
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Narrow band pass filter at RF stage
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| 3. | For an ideal 3000 Hz channel, S/N ratio is ? | |
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3
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1.5
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4
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2
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| 4. | RF amplifiers are used in radio receivers for ? | |
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Improved image frequency rejection
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Improved rejection of adjacent unwanted signals
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Prevention of radiation of the local oscillator through the antenna of the receiver
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All of the other options
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| 5. | During heterodyne process in a receiver the modulation of the signal ? | |
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Is totally eliminated
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Remains unaffected
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Increases
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decreases
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| 6. | AFC and AGC are respectively ? | |
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Audio frequency control and automatic gain control
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Audio frequency control and automatic gate control
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Amplitude frequency control and automatic gain control
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Automatic frequency control and automatic gain control
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| 7. | Modulation of signal during heterodyne process in a receiver ? | |
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Decreases
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Finished totally
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Increases
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Remains unchanged
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| 8. | A super heterodyne receiver with an intermediate frequency of 450 KHz is tuned to a signal at 1100 KHz, the image frequency is ? | |
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650 KHz
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1550 KHz
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800 KHz
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2000 KHz
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| 9. | Which of the following stage in a radio receiver provides the maximum image signal selectivity ? | |
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Frequency mixer
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RF amplifier
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Audio amplifier
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IF amplifier
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| 10. | Value of standard IF of AM receiver is ? | |
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455 KHz
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10.7 MHz
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107 KHz
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455 MHz
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