MCQs in Electronic Circuits, Analysis, Design Part V

This is the Multiples Choice Questions Part 5 of the Series in Electronic (Audio/RF) Circuit/Analysis/Design as one of the Electronics Engineering 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.

Multiple Choice Questions Topic Outline

• MCQs in Amplifiers
• MCQs in Oscillators
• MCQs in Rectifier
• MCQs in Filters
• MCQs in Voltage Regulation

The Series

Following is the list of multiple choice questions in this brand new series:

Electronic Circuits MCQs

PART 1: MCQs from Number 1 – 50                        Answer key: PART I

PART 2: MCQs from Number 51 – 100                   Answer key: PART II

PART 3: MCQs from Number 101 – 150                 Answer key: PART III

PART 4: MCQs from Number 151 – 200                 Answer key: PART IV

PART 5: MCQs from Number 201 – 250                 Answer key: PART V

PART 6: MCQs from Number 251 – 300                 Answer key: PART VI

Continue Practice Exam Test Questions Part 5 of the Series

201. What is the device in a transistor oscillator?

• A. LC tank circuit
• B. Biasing circuit
• C. Transistor
• D. Feedback circuit

202. When the collector supply is 5V, then collector cut off voltage under dc condition is

• A. 20 V
• B. 10 V
• C. 2.5 V
• D. 5 V

203. The common base (CB) amplifier has a ______ compared to CE and CC amplifier.

• A. Lower input resistance
• B. Larger current gain
• C. Larger voltage gain
• D. Higher input resistance

204. When a FET with a lower transconductance is substituted into a FET amplifier circuit, what happens?

• A. The current gain does not change
• B. The voltage gain decreases
• C. The circuit disamplifies
• D. The input resistance decreases

205. At zero signal condition, a transistor sees______ load.

• A. dc
• B. ac
• C. both dc and ac
• D. resistive

206. What is the gain of an amplifier with negative feedback if the feedback factor is 0.01?

• A. 10
• B. 1,000
• C. 100
• D. 500

207. The current gain of an emitter follower is

• A. Equal to 1
• B. Greater than 1
• C. Less than 1
• D. Zero

208. The current in any branch of a transistor amplifier that is operating is

• A. ac only
• B. the sum of ac and dc
• C. the difference of ac and dc
• D. dc only

209. An ideal differential amplifiers common mode rejection ratio is

• A. Infinite
• B. Zero
• C. Unity
• D. Undetermined

210. An open fuse circuit has a resistance equal to

• A. Zero
• B. Unity
• C. At least 100Ω at standard
• D. Infinity

211. What is the purpose of dc conditions in a transistor?

• A. To reverse bias the emitter
• B. To forward bias the emitter
• C. To set up operating point
• D. To turn on the transistor

212. The ac variations at the output side of power supply circuits are called _______.

• A. Ripples
• B. Pulses
• C. Waves
• D. Filters

213. What is the purpose of the emitter capacitor?

• A. To forward bias the emitter
• B. To reduce noise in the amplifier
• C. To avoid drop in gain
• D. To stabilize emitter voltage

214. A common emitter circuit is also called ________ circuit.

• A. Grounded emitter
• B. Grounded collector
• C. Grounded base
• D. Emitter follower

215. The output signal of a common-collector amplifier is always

• A. Larger than the input signal
• B. In phase with the input signal
• C. Out of phase with the input signal
• D. Exactly equal to the input signal

216. Calculate the ripples of the filter output if a dc and ac voltmeter is used and measures the output signal from a filter circuit of 25 VDC and 1.5 V_rms

• A. 5%
• B. 10%
• C. 50%
• D. 6%

217. What is the ideal maximum voltage gain of a common collector amplifier?

• A. Unity
• B. Infinite
• C. Indeterminate
• D. Zero

218. The output power of a transistor amplifier is more than the input power due to additional power supplied by

• A. Transistor
• B. Collector supply
• C. Emitter supply
• D. Base supply

219. When a transistor amplifier feeds a load of low resistance, its voltage gain will be

• A. Low
• B. Very high
• C. High
• D. Moderate

220. The capacitors are considered _________ in the ac equivalent circuit of a transistor amplifier.

• A. Open
• B. Partially open
• C. Short
• D. Partially short

221. For highest power gain, what configuration is used?

• A. CC
• B. CB
• C. CE
• D. CS

222. What is the most important characteristic of a common collector amplifier?

• A. High input voltage
• B. High input resistance
• C. High output resistance
• D. Its being an amplifier circuit

223. Which of the item below does not describe a common emitter amplifier?

• A. High voltage gain
• B. High current gain
• C. Very high power gain
• D. High input resistance

224. CC configuration is used for impedance matching because its

• A. Input impedance is very high
• B. Input impedance is very low
• C. Output impedance is very low
• D. Output impedance is zero

225. Which of the following is the other name of the output stage in an amplifier?

• A. Load stage
• B. Audio stage
• C. Power stage
• D. RF stage

226. When amplifiers are cascaded

• A. The gain of each amplifier is increased
• B. A lower supply voltage is required
• C. The overall gain is increased
• D. Each amplifier has to work less

227. Ina common emitter amplifier, the capacitor from emitter to ground is called the

• A. Coupling capacitor
• B. Bypass capacitor
• C. Decoupling capacitor
• D. Tuning capacitor

228. A class A power amplifier uses ________ transistor(s).

• A. Two
• B. One
• C. Three
• D. Four

229. What is the maximum collector efficiency of a resistance loaded class A power amplifier?

• A. 50%
• B. 78.5%
• C. 25%
• D. 30%

230. What is the maximum collector efficiency of a transformer coupled class A power amplifier?

• A. 30%
• B. 80%
• C. 45%
• D. 50%

231. Class C amplifiers are used as

• A. AF amplifiers
• B. Small signal amplifiers
• C. RF amplifiers
• D. IF amplifiers

232. Find the voltage drop developed across a D’ Arsonval meter movement having an internal resistance of 1 kΩ and a full deflection current of 150uA.

• A. 150 µV
• B. 150 mV
• C. 150 V
• D. 200 mV

233. If the capacitor from emitter to ground in a common emitter amplifier is removed, the voltage gain

• A. Increases
• B. Decreases
• C. Becomes erratic
• D. Remains the same

234. Comparatively, power amplifier has _______ β.

• A. Large
• B. Very large
• C. Small
• D. Very small

235. The driver stage usually employs ________ amplifier.

• A. Class A power
• B. Class C
• C. Push-pull
• D. Class AB

236. The push-pull circuit must use ______ operation.

• A. Class A
• B. Class B
• C. Class C
• D. Class AB

237. A complementary-symmetry amplifier has

• A. One PNP and one NPN transistor
• B. Two PNP transistors
• C. Two NPN transistors
• D. Two PNP and two NPN transistors

238. Power amplifiers generally use transformer coupling because transformer coupling provides

• A. Cooling of the circuit
• B. Distortionless output
• C. Impedance matching
• D. Good frequency response

239. The output transformer used in a power amplifier is a/an _______ transformer

• A. 1:1 ratio
• B. Step-down
• C. Step-up
• D. Isolation

240. Transformer coupling can be used in ___________ amplifiers

• A. Only power
• B. Only voltage
• C. Either power or voltage
• D. Neither power nor voltage

241. When negative current feedback is applied to an amplifier, its output impedance

• A. increases
• B. remains unchanged
• C. decreases
• D. becomes zero

242. The quiescent current of a FET amplifier is

• A. IDS
• B. id
• C. ID
• D. Id

243. The total decibel voltage gain of two cascaded voltage amplifier where individual voltage gains are 10 and 100 is

• A. 20
• B. 60
• C. 800
• D. 1000

244. The frequency response of the combined amplifier can be compared with

• A. An OR gate
• B. A negative feedback amplifier
• C. A positive filter
• D. An AND gate

245. Minimum interference with frequency response can be given by

• A. Direct coupling
• B. RC coupling
• C. Transformer coupling
• D. Instrumentation and control

246. The impedance of a load must match the impedance of the amplifier so that

• A. Minimum power is transferred to the load
• B. The efficiency can be maintained at low level
• C. The signal-to-noise ratio is maximized
• D. Maximum power is transferred to the load

247. The ratio output rms power in watts to the input dc power in watts in the different amplifier class is called _________.

• A. Gain
• B. Amplification factor
• C. Efficiency
• D. Phase power

248. Consider a zener diode with a slope resistance of 10 Ω in series with a 90 Ω resistor fed from a dc supply containing a ripple voltage of 20mV peak-to-peak. Compute for the ripple voltage in load

• A. 1 mV p-p
• B. 2 mV p-p
• C. 1 V p-p
• D. 6mV p-p

249. The ________ of a common collector configuration is unity

• A. Voltage gain
• B. Current gain
• C. Power gain
• D. Input impedance

250. Transmit time is the time taken by the electrons on holes to pass from

• A. Emitter to collector
• B. Collector to emitter
• C. Base to emitter
• D. Base to collector

Complete List of MCQs in Electronics Engineering per topic

Series of Multiple Choice Questions in Electronics Engineering

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