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  • Question

  • Assertion (A): Gunn diode is a transferred electron device.

    Reason (R): A Gunn oscillator uses the phenomenon of transferred electron effect.


  • Options
  • A. Both A and R are correct and R is correct explanation of A
  • B. Both A and R are correct but R is not correct explanation of A
  • C. A is correct but R is wrong
  • D. A is wrong but R is correct

  • Correct Answer
  • Both A and R are correct but R is not correct explanation of A 

    Explanation
    A Gunn diode uses GaAs which has a negative differential mobility, i.e., a decrease in carrier velocity with increase in electric field.

    This effects is called transferred electron effect. The impedance of a Gunn diode is tens of ohms.

    A Gunn diode oscillator has a resonant cavity, an arrangement to couple Gunn diode to cavity, biasing arrangement for Gunn diode and arrangement to couple RF power to load.

    Applications of Gunn diode oscillator include continuous wave radar, pulsed radar and microwave receivers.

    More questions

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    • C. band pass filter
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    • Options
    • A. True
    • B. False
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    • 3. The household radio receiver uses

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    • A. synchronous
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    • C. radio detector
    • D. none of the above
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    • Options
    • A. Auxiliary commutated
    • B. Jones chopper
    • C. Morgan chopper
    • D. Load commutated
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    • 5. For an illumination control circuit it is advisable to use a matched TRIAC-DIAC pair.

    • Options
    • A. True
    • B. False
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    • Options
    • A. reduced losses
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    • A. True
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    • Options
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    • D. none of the above
      • Discuss
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    • Options
    • A. True
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    • Options
    • A. 16
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    • C. 1024
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