Electronic Devices-Power Amplifiers
Electronic Devices-Power Amplifiers
21. By how much does the output signal vary for a class AB power amplifier?
- 360º
- 180º
- Between 180º and 360º
- Less than 180º
22. Which type of amplifier uses pulse (digital) signals in its operation?
- Class A
- Class B or AB
- Class C
- Class D
23. Which of the push-pull amplifiers is presently the most popular form of the class B power amplifier?
- Quasi-complementary
- Transformer-coupled
- Complementary-symmetry
- None of the above
24. Calculate the harmonic distortion component for an output signal having a fundamental amplitude of 3 V and a second harmonic amplitude of 0.25 V.
- 3.83%
- 38.3%
- 8.33%
- 83.3%
25. Which amplifier is commonly used as a frequency multiplier?
- class A
- class B
- class C
- all of the above
26. A class B amplifier operates in the linear region for
- slightly more than 180° of the input cycle.
- 360° of the input cycle.
- slightly less than 180° of the input cycle.
- much less than 180° of the input cycle.
27. Which of the following instruments displays the harmonics of a distorted signal?
- Digital multimeter
- Spectrum analyzer
- Oscilloscope
- Wave analyzer
28. Calculate the efficiency of a transformer-coupled class A amplifier for a supply of 15 V and an output of V(p) = 10 V.
- 25%
- 33.3%
- 50%
- 78.5%
29.
________ amplifiers primarily provide sufficient power to an output load to drive a speaker from a few watts to tens of watts.
________ amplifiers primarily provide sufficient power to an output load to drive a speaker from a few watts to tens of watts.
- Small-signal
- Power
- None of the above
30. You have an application for a power amplifier to operate on FM radio frequencies. The most likely choice would be a ________ amplifier.
- class A
- class B
- class C
- class AB