61. Which coupling produces the minimum interference with frequency response
a. RC coupling
b. Transformer coupling
c. Direct coupling
d. Impedance coupling

62. Complementary symmetry use two transistor that are
a. both NPN
b. both PNP
c. PNP and NPN
d. both FET

63. Which of the following circuits can operate class AB for audio power output?
a. Emitter follower
b. Push pull
c. Cascade
d. Darlington pair

64. A dc amplifier
a. dc only
b. ac only
c. both ac and dc
d. neither of the above

65. A bipolar transistor is a ………. controlled device whereas a FET is a ………… controlled device
a. Current-voltage
b. Current-current
c. Voltage – current
d. Voltage -voltage

66. Which of the following devices acts as an NPN and PNP transistor connected base to base and emitter to collector?
a. UJT
b. SCR
c. Diac
d. Triac

67. Which of the following is the fastest switching device/
b. BJT
d. Triode

68. Which of the following statement is false?
a. The zener diode is used as a constant voltage source
b. The SCR is a silicon rectifier with a gate electrode to control when current flows from cathode to anode
c. The gate electrode in the FET corresponds to the collector in a bipolar transistor
d. None of the above

69. Which of the following is the point of reference JFET
a. Drain
b. Gate
c. Source
d. None of the above

70. A junction field effect transistor can operate in
a. depletion mode only
b. enhancement mode only
c. depletion and enhancement modes
d. neither depletion nor enhancement modes