66. Shot noise is caused by—

1. 1. Random variations in the arrival of electrons at the collector

   
   
   

   2. Random variations in the arrival of holes at the collector

   
   
   

   3. Random variations in the arrival of both electrons and holes at the collector

   
   
   

   4. None of the above

   
   
   

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   NA

   Correct Option: A

   NA

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67. In case of a resistor all of the following are the same except—

1. 1. Thermal noise

   
   
   

   2. Shot noise

   
   
   

   3. Johnson noise

   
   
   

   4. White noise

   
   
   

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   NA

   Correct Option: B

   NA

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68. Transistors are generally free from which type of noise?

1. 1. Resistance noise

   
   
   

   2. Flicker noise

   
   
   

   3. Shot noise

   
   
   

   4. Partition noise

   
   
   

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   NA

   Correct Option: D

   NA

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69. Which of the following measures cannot be effective in reducing the noise?

1. 1. Reduction in signalling rate

   
   
   

   2. Increase in transmitted power

   
   
   

   3. Increase in channel bandwidth

   
   
   

   4. Use of redundancy

   
   
   

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   NA

   Correct Option: C

   NA

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70. Quantising noise is produced in—

1. 1. FDM

   
   
   

   2. PCM

   
   
   

   3. all modulation system

   
   
   

   4. all pulse, modulation system

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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