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ECE :: Analog Electronics

  1. When a transistor is to be at a temperature above 25°C

  2. A.
    smaller heat sink be provided
    B.
    maximum power rating be derated
    C.
    biasing circuit must be strengthened
    D.
    earth connections must be connected through a resistor

  3. Assertion (A): In monolithic IC the components are part of one chip

    Reason (R): An op-amp is a high gain dc amplifier

  4. A.
    Both A and R are correct and R is correct explanation for A
    B.
    Both A and R are correct but R is not correct explanation for A
    C.
    A is correct R is wrong
    D.
    A is wrong R is correct

  5. The most widely used LC oscillator is

  6. A.
    Hartley oscillator
    B.
    Crystal oscillator
    C.
    Colpitt's oscillator
    D.
    Clapp's oscillator

  7. Which of the following statement is wrong?

  8. A.
    A depletion type N-channel MOSFET conducts even when VGS = 0
    B.
    A BJT is very sensitive to radiation whereas FET is relatively immune
    C.
    Bipolars need higher supply voltage than FETs
    D.
    Both N-channel as well as p-channel JFETs work in the depletion mode

  9. The disadvantage of FET over BJT is

  10. A.
    poor high frequency performance
    B.
    low power-handling ability
    C.
    low values of voltage gain
    D.
    all of the above

  11. In a self bias circuit for CE amplifier, the base voltage is

  12. A.
    equal to supply voltage
    B.
    more than supply voltage
    C.
    equal to or more than supply voltage
    D.
    less than supply voltage

  13. A push pull amplifier is a

  14. A.
    power amplifier
    B.
    voltage amplifier
    C.
    current amplifier
    D.
    both power and current amplifier

  15. An engineer designs an amplifier to have a voltage gain of 60, but when constructed it only had a gain of 50. How much feedback should be used to provide the desired level?

  16. A.
    +0.03%
    B.
    +0.33%
    C.
    +1.30%
    D.
    +3.3%

  17. Which of the following oscillator circuits uses three capacitors in the phase shifting network?

  18. A.
    Hartley
    B.
    Clapp
    C.
    Colpitt's
    D.
    Both (b) and (c)

  19. Consider the following rectifier circuits :

    1. half-wave rectifier without filter
    2. full-wave rectifier without filter
    3. full-wave rectifier with series inductance filter
    4. full-wave rectifier with capacitance filter.
    The sequence of these rectifier circuits in decreasing order of their ripple factor is

  20. A.
    1, 2, 3, 4
    B.
    3, 4, 1, 2
    C.
    1, 4, 3, 2
    D.
    3, 2, 1, 4