Home / EEE / Transistor Audio Power Amplifiers :: section-1

EEE :: Transistor Audio Power Amplifiers

  1. The output stage of a multistage amplifier usually employs ___________

  2. A.

     Push-pull amplifier

    B.

     Preamplifier

    C.

     Class A power amplifier

    D.

     None of the above


  3. ___________ coupling is generally employed in power amplifiers

  4. A.

     Transformer

    B.

     RC

    C.

     direct

    D.

     Impedance


  5. The class B push-pull circuit can deliver 100 W of a.c. output power. What should be the minimum power rating of each transistor?

  6. A.

     20 W

    B.

     40 W

    C.

     10 W

    D.

     80 W


  7. The maximum efficiency of resistance loaded class A power amplifier is

  8. A.

     5%

    B.

     50%

    C.

     30%

    D.

     25%


  9. The disadvantage of impedance matching is that it ___________

  10. A.

     Gives distorted output

    B.

     Gives low power output

    C.

     Requires a transformer

    D.

     None of the above


  11. In class A operation, the operating point is generally located ___________ of the d.c. load line.

  12. A.

     At cut off point

    B.

     At the middle

    C.

     At saturation point

    D.

     None of the above


  13. The output transformer used in a power amplifier is a ___________ transformer

  14. A.

     1:1 ratio

    B.

     Step-up

    C.

     Step-down

    D.

     None of the above


  15. Transformer coupling can be used in ___________ amplifiers

  16. A.

     Either power or voltage

    B.

     Only power

    C.

     Only voltage

    D.

     None of the above


  17. A 2-transistor class B power amplifier is commonly called ___________ amplifier

  18. A.

     Dual

    B.

     Push-pull

    C.

     Symmetrical

    D.

     Differential


  19. A class A power amplifier is sometimes called ___________ amplifier

  20. A.

     Symmetrical

    B.

     Single-ended

    C.

     Reciprocating

    D.

     Differential