MCQ in Electronic Circuits Part 4 | ECE Board Exam

This is the Multiple Choice Questions in Electronic Circuits (Electronic Devices and Circuits, Electronic Circuit Analysis and Design) Part 4 of the Series as one of the Electronics Engineering Examination topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.

MCQ Topic Outline included in ECE Board Exam Syllabi

4. Electronic Devices and Circuits

• MCQ in Diode Wave Shaping Circuits and Special Diode Applications
• MCQ in BJT and FET Small Signal Analysis
• MCQ in Diode Equivalent Circuits
• MCQ in Voltage Multipliers, Power Supply, and Voltage Regulation
• MCQ in Bipolar Junction Transistor and FET

5. Electronic Circuit Analysis and Design

• MCQ in BJT and FET Frequency Response
• MCQ in Cascade and Cascode Connections
• MCQ in Current Mirrors and Current Source
• MCQ in Differential and Operational Amplifier
• MCQ in Feedback Systems, Oscillators, and Filters

Continue Practice Exam Test Questions Part 4 of the Series

⇐ MCQ in Electronic Circuits Part 3 | ECE Board Exam

Choose the letter of the best answer in each questions.

151. In a Colpitt’s oscillator, feedback is obtained

A. By magnetic induction

B. By a tickler coil

C. From the center of split capacitors

D. From the center of split inductors

152. When the collector resistor in a common emitter amplifier is increased in value the voltage gain

A. Increases

B. Decreases

C. Remain the same

D. Becomes erratic

153. The output signal of CE amplifier is always

A. Out of phase with the input signal

B. Equal to the input signal

C. In phase with the input signal

D. Larger than the input signal

154. What is the purpose of capacitors in a transistor amplifier?

A. To protect the transistor

B. To cool the transistor

C. To couple or bypass ac component

D. To provide biasing

155. What is the phase difference between voltage across collector load and signal voltage in a common emitter amplifier?

A. 0°

B. 270°

C. 180°

D. 90°

156. When CE configuration is used for an oscillator, the voltage fed back must

A. Be inverted by 180°

B. Be taken from a capacitor

C. Have a 0° phase shift

D. Taken from an inductor

157. Class B operation has a maximum possible frequency of ___________ percent.

A. 100%

B. 78.5%

C. 75%

D. 2.2%

158. What is the most stable sine-wave oscillator which uses piezo-electric quartz crystal?

A. Crystal oscillator

B. Wien-bridge oscillator

C. DC restorer

D. Hartley and Colpitts oscillator

159. To sustain oscillations, the power gain of the amplifier may be

A. Between 0.1 and 0.5

B. Any value form 0.5 upward

C. Equal to or greater than 1

D. Infinite

160. In a phase shift oscillator, 180° phase-shift is obtained

A. A transformer

B. LC tank circuit

C. Three RC sections

D. Three LC sections

161. Feedback circuit usually employs __________ network

A. Resistive

B. Inductive

C. Capacitive

D. Active

162. Emitter follower is used for

A. Impedance matching

B. Voltage gain

C. Current gain

D. Power gain

163. One of the items below is a characteristic of cascaded amplifiers?

A. Doubles transconductance

B. Total gain is lessen

C. Increased overall gain

D. Increased overall amplification ratio

164. Logic analyzer is used to

A. Verify the logic operation of the gates in a circuit

B. To display the fall time

C. To sample and display systems signal

D. To analyze the logic operation of the system

165. Quartz crystal is most commonly used in crystal oscillators because

A. It is easily available

B. It has superior electrical properties

C. It is quite inexpensive

D. It is very rugged

166. The operating frequency of a Wien-bridge oscillator is given by

A.

B.

C.

D.

167. Which operation gives the maximum distortion?

A. Class A

B. Class C

C. Class B

D. Class AB

168. Low efficiency of a power amplifier results in

A. Low forward bias

B. Less battery consumption

C. More battery consumption

D. Low power output

169. In an LC oscillator, the frequency of oscillations is given by

A.

B.

C.

D.

170. Class A operation has a maximum possible efficiency of ___________ percent.

A. 100%

B. 50%

C. 75%

D. 25%

171. Which of the following amplifier below is a choice when higher power gain is a requirement?

A. Common base

B. Common emitter

C. Common collector

D. Hybrid connection

172. The signal generator generally used in laboratories is ____________ oscillator

A. Crystal

B. Wien-bridge

C. Hartley

D. Phase-shift

173. A buffer amplifier is used for

A. Maximum loading and minimum mismatch

B. Minimum loading and minimum mismatch

C. Maximum loading and maximum mismatch

D. Minimum loading and maximum mismatch

174. Parasitic oscillations are caused by

A. Output negative feedback

B. Push-pull operation

C. Poor interstage coupling

D. Transistor interelectrode capacitance

175. Which is a fixed-frequency oscillator

A. Phase-shift oscillator

B. Colpitt’s oscillator

C. Hartley oscillator

D. Crystal oscillator

176. The approximate operating frequency of a phase shift oscillator is given by

A.

B.

C.

D.

177. The frequency of the ripple voltage at the output of a full-wave rectifier at 60 cycles.

A. 120 cycles

B. 60 cycles

C. 240 cycles

D. 480 cycles

178. Cascaded amplifiers total decibel gain is equal to

A. The sum of the individual gains

B. The product of the individual gains

C. The difference of the individual gains

D. The quotient of the individual gains

179. In an LC oscillator, if the value of L is increased four times, then the frequency of oscillation is

A. Decreased 2 times

B. Decreased 4 times

C. Increased 2 times

D. Increased 4 times

180. A class A power amplifier is otherwise known as

A. Single ended amplifier

B. Darlington amplifier

C. Symmetrical amplifier

D. Differential amplifier

181. The power input to a power amplifier is __________ quantity.

A. ac

B. Pulsating dc

C. dc

D. sinusoidal

182. When shock-excited, a crystal will produce alternating emf longer than an LC circuit because

A. has greater mechanical strength

B. has fewer losses

C. is small-sized

D. is very rigid

183. The stability of a regulated power supply is equivalent to

A. change of output voltage over the change in supply voltage

B. change in supply voltage over the change of output voltage

C. product of the output voltage and supply voltage

D. the difference of an output voltage to its supply voltage

184. What oscillator circuit uses a tapped coil in the tuned circuit?

A. Hartley

B. Colpitts

C. Crystal

D. Pierce

185. If you move towards an oscillating circuit, its frequency changes because of

A. Hand capacitance

B. Movement of the body

C. Noise of foot

D. Stray capacitance

186. Which of the following is not a FET amplifier configuration?

A. Common base amplifier

B. Common drain amplifier

C. Common source amplifier

D. Common gate amplifier

187. The number of transistor in a single stage amplifier is

A. Two

B. Three

C. One

D. Four

188. Series current negative feedback occurs when the feedback voltage is proportional to the output

A. Voltage

B. Impedance

C. Current

D. Power

189. Which of the following is NOT an oscillator requirement?

A. Attenuator

B. Amplifier

C. Tank circuit

D. Feedback

190. An amplifier with efficiency of 85% is likely to be

A. Class A

B. Class B

C. Class AB

D. Class C

191. What is the phase difference between the output and the input voltage of a CE amplifier?

A. 180°

B. 270°

C. 0°

D. 90°

192. Class C operation is preferred in oscillators because it

A. Is more efficient

B. Gives larger outputs

C. Produces square waves

D. Increases stability

193. What type of oscillator which is composed of one or more amplifying devices with some frequency determining networks introducing positive feedback at a particular frequency so that oscillation is sustained at that frequency?

A. Sine wave oscillator

B. Square-wave generator

C. Relaxation oscillator

D. Limiter

194. What is the desired input impedance of a transistor?

A. Low

B. Very low

C. High

D. Very high

195. What is the maximum collector efficiency of class B?

A. 50%

B. 90%

C. 60.5%

D. 78.5%

196. When a transistor is cut off

A. Maximum current flows

B. Maximum voltage appears across load

C. Maximum voltage appears across transistor

D. Minimum current flows

197. In an LC circuit, when the capacitor energy is maximum, the inductor energy is

A. Maximum

B. Minimum

C. Half-way between maximum and minimum

D. Zero

198. What is the approximate gain of an amplifier with negative feedback?

A. The feedback factor

B. The reciprocal of feedback factor plus one

C. The reciprocal of feedback factor

D. The feedback factor plus one

199. The operating point in a transistor amplifier moves along ___________ when an ac signal is applied

A. dc load line

B. ac load line

C. both dc and ac load lines

D. cut-off

200. An oscillator converts

A. ac power into dc power

B. dc power into ac power

C. mechanical power into ac power

D. electrical power into mechanical power

Questions and Answers in Electronic Circuits

Following is the list of practice exam test questions in this brand new series:

Complete List of MCQ in Electronics Engineering per topic