5. [ELEX]

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116. Generally tuned amplifiers are operated in A. Class C B. Class A C. Class B D. Class AB

A

117. A tuned amplifier is used in what application? A. Radio frequency B. Audio frequency C. Intermediate frequency D. Low frequency

A

119. For a constant output frequency, the simplest sinusoidal oscillator is the ___________. A. Crystal oscillator B. Phase-shift circuit C. Colpitts circuits D. Hartley circuit

A

123. What is the disadvantage of impedance matching? A. It gives distorted output B. It requires a transformer C. It gives low power output D. It is expensive

A

124. In a phase-shift oscillator, ____________ RC sections are generally used. A. Three B. Four C. Two D. Five

A

126. When the gain is 20 without feedback and 12 with negative feedback, feedback factor is A. 0.033 B. 3/5 C. 5/3 D. 1/5

A

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°

A

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

A

16. Oscillators operate on the principle of A. Positive feedback B. Negative feedback C. Signal feedthrough D. Attenuation

A

161. Feedback circuit usually employs __________ network A. Resistive B. Inductive C. Capacitive D. Active

A

162. Emitter follower is used for A. Impedance matching B. Voltage gain C. Current gain D. Power gain

A

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

A

18. What happens if the input capacitor of a transistor amplifier is short-circuited? A. Biasing conditions will change B. Transistor will be destroyed C. Signal will not reach the base D. Biasing will stabilize

A

205. At zero signal condition, a transistor sees ___________ load. A. dc B. ac C. both dc and ac D. resistive

A

209. An ideal differential amplifiers common mode rejection ratio is A. Infinite B. Zero C. Unity D. Undetermined

A

21. What is a non-linear type of amplifier? A. Class C B. Class AB C. Class B D. Class A

A

212. The ac variations at the output side of power supply circuits are called ___________. A. Ripples B. Pulses C. Waves D. Filters

A

249. The __________ of a common collector configuration is unity A. Voltage gain B. Current gain C. Power gain D. Input impedance

A

26. Class C is an amplifier whose output current flows for A. Less than one-half the entire input cycle B. The entire input cycle C. Twice the entire input cycle D. Greater than one-half the entire input cycle

A

268. In order to have the best efficiency and stability, where at the loadline should a solid state power amplifier be operated? A. Just below the saturation point B. At 1.414 times the saturation point C. Just above the saturation point D. At the saturation point

A

277. Two class B amplifiers connected such that one amplifies the positive cycle and the other amplifies the remaining negative cycle. Both output signals are then coupled by a transformer to the load. A. transformer-coupled push -pull amplifier B. complementary-symmetry amplifier C. quasi-complementary push-pull amplifier D. transformer-coupled class A amplifier

A

28. The collector current in an common base configuration is equal to A. Alpha times emitter current plus leakage current B. Alpha times base current plus leakage current C. Beta times emitter current plus leakage current D. Beta times collector current plus leakage current

A

281. Basically, which class of amplifiers has the least distortion? A. class A B. class B C. class C D. class D

A

307. A good op-amp has a A. very high input resistance B. very low input resistance C. very high output resistance D. very low CMRR

A

35. The basic concept of the electric wave filter was originated by A. Campbell and Wagner B. Norton C. Foster D. Bode and Darlington

A

376. The voltage gain of an op-amp voltage follower. A. unity B. Rf/Ri C. 1 + Rf/Ri D. depends on the type of op-amp

A

377. Calculate the closed-loop voltage gain of an inverting amplifier having a feedback and an input resistance of 100 kΩ and 10 kΩ, respectively. A. 10 B. 11 C. 100 D. 110

A

43. An ammeter's ideal resistance should be A. Zero B. Unity C. Infinite D. The same with the circuits resistance

A

435. In most transistor input equivalent circuit it comprises of a resistor and a A. voltage source B. stiff voltage source C. current source D. stiff current source

A

436. Considered as the basic FET or the simplest form of FET A. JFET B. MOS-FET C. IGFET D. VMOS-FET

A

448. If the feedback signal (voltage or current) is applied in such a way that it is in phase with the input signal and thus increases. It is also known as regenerative feedback or direct feedback a. Positive Feedback b. Negative Feedback c. Stabilized Feedback d. Impedance Feedback

A

496. What is the resonant frequency of a circuit when L is 1 microhenry and C is 10 picofarads are in series? a. 50.3 MHz b. 15.9 MHz c. 15.9 kHz d. 50.3 kHz

A

530. Which of the following is true for an NPN or PNP transistor? A. ie = ib + ic B. ib = ic+ ie C. ic = ib + ie D. none of the above

A

554. For audio systems, the reference level is generally accepted as . A. 1 mw B. 1 w C. 10 mw D. 100 mw

A

583. The ac variations at the output side of power supply circuits are called . A. ripples B. pulses C. waves D. filters

A

585. A common emitter circuit is also called circuit. A. grounded emitter B. grounded collector C. grounded base D. emitter follower

A

590. When a transistor amplifier feeds a load of low resistance, its voltage gain will be A. low B. very high C. high D. moderate

A

621. An open-drain gate is the CMOS counterpart of A. an open-collector TTL gate B. a tristate TTL gate C. a bipolar junction transistor D. an emitter- coupled logic gate

A

653. Which of the following is the passive element? A. capacitance B. ideal current source C. ideal voltage source D. all of the above

A

677. Fan-out for a typical TTL gate is A. 10 B. 4 C. 54 D. 100

A

7. Which of the following is considered an amplifier figure of merit? A. Gain-bandwidth product B. Beta (β) C. Alpha (α) D. Temperature

A

702. The ______ of a common collector configuration is unity A. voltage gain B. current gain C. power gain D. input impedance

A

728. The main use of a class C amplifier is A. as an RF amplifier B. as stereo amplifier C. in communication sound equipment D. as distortion generator

A

740. In power amplifiers, the output signal varies for a full 360° of the cycle. A. class a B. class b or ab C. class c D. class d

A

756. The fundamental component is typically any harmonic component. A. larger than B. the same as C. smaller than D. none of the above

A

788. Kirchhoff's Voltage Law states that the total voltage around a closed loop must be A. 0 B. ½ C. 1 D. 2

A

398. Example(s) of surface-mounted technology (SMT) devices. A. PLCCs B. SOICs C. LCCCs D. all of the above

D

405. A microwave oscillator A. Hartley oscillator B. Colpitts oscillator C. Relaxation oscillator D. Klystron oscillator

D

41. A multistage amplifier uses at least how many transistors? A. One B. Three C. Four D. Two

D

410. Monostable multivibrator is also known as A. one shot B. single shot C. direct shot D. one shot or single shot

D

411. What determines the pulse time in a monostable multivibrator? A. resistor combinations B. capacitor combinations C. inductor combinations D. resistor and capacitor combinations

D

507. A FET consists of a A. source B. drain C. gate D. all the above

D

513. Junction Field Effect Transistors (JFET) contain how many diodes? A. 4 B. 3 C. 2 D. 1

D

541. What type(s) of gate-to-source voltage(s) can a depletion MOSFET (D-MOSFET) operate with? A. zero B. positive C. negative D. any of the above

D

545. If VD is less than expected (normal) for a self-biased JFET circuit, then it could be caused by a(n) A. open rg. B. open gate lead. C. fet internally open at gate. D. all of the above

D

549. The output voltage of a CE amplifier is A. amplified B. inverted C. 180° out of phase with the input D. all of the above

D

553. Which of the following elements are important in determining the gain of the system in the high-frequency region? A. interelectrode capacitances B. wiring capacitances C. miller effect capacitance D. all of the above

D

558. A current ratio of IC/IE is usually less than one and is called A. omega B. beta C. theta D. alpha

D

559. A transistor may be used as a switching device or as a: A. tuning device B. rectifier C. fixed resistor D. variable resistor

D

667. Unused inputs on TTL, AND, and NAND gates A. degrade the gate's noise immunity. B. if left open will have the same effect as high inputs. C. should be tied high. D. all of the above are correct.

D

669. The input transistor on a TTL circuit is unusual in that it has A. multiple bases. B. no collector. C. no base. D. multiple emitters.

D

671. The upper transistor of a totem-pole output is OFF when the gate output is A. logic 1. B. malfunctioning. C. high. D. low.

D

674. The maximum current for a LOW output on a standard TTL gate is A. 16 µa. B. 40 ma. C. 100 µa. D. 16 ma.

D

678. In order to interface an FPGA with an external device, you must set the value of the A. sink current. B. external power supply. C. source current. D. all of the above

D

687. Each input on a TTL gate is connected to the transistor's A. base B. collector C. gate D. emitter

D

692. The fan out of a MOS logic gate is higher than that of TTL gates because of its A. low input impedance B. high output impedance C. low output impedance D. high input impedance

D

697. 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

D

699. 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

D

705. A class A amplifier has a voltage gain of 30 and a current gain of What is the power gain? A. 30 B. 25 C. 1.2 D. 750

D

712. The maximum efficiency of a class B amplifier is percent. A. 50 B. 25 C. 70 D. 79

D

758. Improvement in production techniques of power transistors have ______. A. produced higher power ratings in small-sized packaging cases B. increased the maximum transistor breakdown voltage C. provided faster- switching power transistors D. all of the above

D

764. Which type of amplifier uses pulse (digital) signals in its operation? A. class a B. class b or ab C. class c D. class d

D

766. Which of the following describe(s) a power amplifier? A. it can handle large power. B. it can handle large current. C. it does not provide much voltage gain. D. all of the above

D

791. The concept on which Superposition theorem is based is A. reciprocity B. duality C. non-linearity D. linearity

D

25. The ear is not sensitive to ____________ distortion. A. Frequency B. Amplitude C. Harmonic D. Phase

A

372. What gain is significant when an op-amp is used as a voltage comparator? A. open-loop gain B. common gain C. differential closed loop gain D. closed loop gain

A

374. The feedback element of a differentiator constructed from op-amp is A. a resistor B. an inductor C. a capacitor D. an RC network

A

379. What is the noise gain of op-amps? A. equal to the open loop gain B. Rf/Ri C. 1 + Rf/Ri D. equal to the common gain

C

396. Dual-in-line or DIL package is designated as A. TO-99 B. TO-91 C. TO-116 D. TO-220

C

401. Circuits that produces alternating or pulsating current or voltage. A. Damper B. Generator C. oscillator D. mixer

C

402. What do you call the oscillator circuit that uses a tapped coli in the tuned circuit? A. Pierce B. Colpitts C. Hartley D. Ultraudion

C

423. Transistor configuration known to have a super-beta (β2). A. cascade B. cascode C. darlington D. differential

C

425. The flow of electron in a NPN transistor when used in electronic circuit is from _______. A. collector to base B. collector to base C. emitter to collector D. base to emitter

C

426. Which of the three regions/areas in a transistor that is the smallest in construction? A. emitter B. collector C. base D. all are equal

C

432. Which transistor configuration has the highest input resistance? A. common base B. common emitter C. common collector D. common transistor

C

433. Calculate the common-emitter amplification factor β of a transistor with a common-base amplification factor α = 0.99. A. 10 B. 50 C. 100 D. 200

C

437. Junction field effect transistor or JFET has three terminals, which corresponds to the E-B-C of the BJT? A. D-S-G B. D-G-S C. S-G-D D. S-D-G

C

44. What circuit increases the peak -to-peak voltage, current or power of a signal? A. Power supply B. Attenuator C. Amplifier D. Filter

C

745. A form of class A amplifier having maximum efficiency of ____ uses a transformer to couple the output signal to the load. A. 90% B. 78.50% C. 50% D. 25%

C

748. The slope of the ac load line in the class A transformer-coupled transistor is . A. -1/RL (load resistor) B. 1/(a2RL) C. -1/(a2RL) D. 1/RL

C

753. The highest efficiency is obtained in class B operation when the level of VL(p) is equal to . A. 0.25vcc B. 0.50vcc C. vcc D. 2vcc

C

760. The has the hottest temperature in a power transistor. A. heat sink B. case C. junction D. none of the above

C

111. When negative voltage feedback is applied to an amplifier, its output impedance A. Remains unchanged B. Decreases C. Increases D. Becomes zero

B

37. Which transistor configuration offers no phase reversal at the output? A. Common-base B. Common-collector C. Common-emitter D. Both A and B

D

371. Two comparators using op-amps, configured such that it can detect voltage levels within a certain range of values rather than simply comparing whether a voltage is above or below a certain reference. A. analog comparator B. regenerative comparator C. parallel comparator D. window comparator

D

373. An op-amp zero-crossing detector without hysteresis, A. uses a resistor as its feedback element B. uses a capacitor as its feedback element C. uses an inductor as its feedback element D. has no feedback

D

378. The gain of an inverting amplifier is determined by the ratio of the feedback and input resistors (Rf/Ri), meaning we can select any value of resistors as long as its ratio is the same. What op-amp parameter that helps us determine the appropriate values of these resistors? A. CMRR B. PSRR C. SR D. input bias current

D

381. The random voltage at the output of an op-amp which could occupy the entire bandwidth. A. noise B. hash C. interference D. all of the above

D

619. A Darlington pair is used for A. low distortion B. high frequency range C. high power gain D. high current gain

D

633. Kirchhoff s law is applicable to A. passive networks only B. a.c. circuits only C. d.c. circuits only D. both a.c. as well d.c. circuits

D

711. Class amplifiers are normally operated in a push-pull configuration in order to produce an output that is a replica of the input. A. a B. b C. c D. ab

D

713. A class amplifier is biased slightly above cutoff and operates in the linear region for slightly more than 180° of the input cycle. A. a B. b C. c D. ab

D

723. What is the maximum efficiency of a class A circuit with a direct or series-fed load connection? A. 90% B. 78.50% C. 50% D. 25%

D

725. Which of the following is (are) power amplifiers? A. class a B. class b or ab C. class c or d D. all of the above

D

729. The decibel is a measure of A. power B. voltage C. current D. sound level

D

732. The maximum efficiency of resistance loaded class A power amplifier is A. 5% B. 50% C. 30% D. 25%

D

738. Power amplifiers primarily provide sufficient power to an output load, typically from to . A. a few kw, tens of kw B. 500 w, 1 kw C. 100 w, 500 w D. a few w, tens of w

D

137. What is the axis that connects the corners of a crystal? A. X B. Mechanical C. Y D. Z

A

38. The number of stages that can be directly coupled is limited because A. Change in temperature can cause thermal instability B. Circuit becomes heavily and costly C. It becomes difficult to bias the circuit D. Circuits' resistance becomes too large

A

39. The input capacitor in an amplifier is called _____________ capacitor. A. Coupling B. Stray C. Bypass D. Electrolytic

A

392. The magnitude of the op-amps input offset voltage before it can be classified as a low-input offset voltage op-amp A. 0.2 mV B. 2.0 mV C. 2.5 mV D. 5.0 mV

A

409. A multivibrator that generates one output pulse for each input trigger pulse. A. monostable B. astable C. bistable D. tristate

A

635. The resistance LM will be A. 6.66 q B. 12 q C. 18 q D. 20 q

A

643. The circuit has resistors, capacitors and semi-conductor diodes. The circuit will be known as A. non-linear circuit B. linear circuit C. bilateral circuit D. none of the above

A

658. A delta circuit has each element of value R/2. The equivalent elements of star circuit with be A. rig B. r/3 C. 2r D. 3r

A

659. While calculating Rth in Thevenin's theorem and Norton equivalent A. all independent sources are made dead B. only current sources are made dead C. only voltage sources are made dead D. all voltage and current sources are made dead

A

779. nMOS and pMOS transistors can be used for class B. A. true B. false

A

10. What type of coupling is generally used in power amplifiers? A. Transformer B. Direct C. RC D. Inductive

A

101. The three amplifiers are connected in a multistage arrangement each with a voltage gain of 30. Compute for the overall voltage gain. A. 90 B. 27,000 C. 10 D. 30

A

103. The gain of an amplifier with feedback is known as __________ gain. A. Closed loop B. Resonant C. Open loop D. Unity

A

108. In practice, what is normally varied in order to change the frequency of oscillation? A. Capacitance B. Inductance C. Resistance D. Impedance

A

11. Which amplifier whose output current flows for the entire cycle? A. Class A B. Class B C. Class C D. Class AB

A

113. A transistor converts A. Dc power into ac power B. Ac power into dc power C. High resistance into low resistance D. Low resistance into high resistance

A

114. Hartley oscillator is commonly used in which of the following? A. Radio receivers B. TV receivers C. Radio transmitters D. CATV

A

129. An important limitation of crystal oscillator is A. Its low output B. Its high Q C. Less availability of quartz crystal D. Its high output

A

13. What is the point of intersection of dc and ac load lines called? A. Operating point B. Cut off point C. Saturation point D. Breakdown

A

134. What is the piezoelectric effect in a crystal? A. Voltage is developed because of mechanical stress B. Change in resistance because of temperature C. Change of frequency because of temperature D. Current is developed due to force applied

A

135. The input resistance of a common emitter amplifier is affected by A. Re, re and β B. Rc and re C. β and re D. α and re

A

138. Determine the attenuation in dB for a T-pad for which R1=R2=40Ω and R3= 36 Ω. The pad connects a 50 Ω generator to a 50 Ω load. A. 9.83 dB B. 83.93 dB C. 10.83 dB D. 11.93 dB

A

141. When crystal frequency increases with temperature, it has ______________ temperature co- efficient. A. Positive B. Negative C. Zero D. Infinite

A

142. What is the purpose of the bypass capacitor in a common-emitter amplifier? A. It increases voltage gain B. It decreases voltage gain C. It provides ac grounding D. No effect in the circuit

A

148. What application where one would most likely find a crystal oscillator? A. Radio transmitter B. AF generator C. Radio receiver D. Oscilloscope

A

149. What is the most important consideration in power amplifiers? A. Collector efficiency B. Biasing the circuit C. To keep the transformer cool D. Amplifier distortion

A

15. What is the operating point in the characteristic curve called? A. Quiescent point B. Load point C. Biasing point D. Saturation point

A

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

A

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

A

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

A

169. In an LC oscillator, the frequency of oscillations is given by A. B. C. D.

A

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

A

180. A class A power amplifier is otherwise known as A. Single ended amplifier B. Darlington amplifier C. Symmetrical amplifier D. Differential amplifier

A

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

A

184. What oscillator circuit uses a tapped coil in the tuned circuit? A. Hartley B. Colpitts C. Crystal D. Pierce

A

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

A

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

A

189. Which of the following is NOT an oscillator requirement? A. Attenuator B. Amplifier C. Tank circuit D. Feedback

A

19. Which is used to establish a fixed level of current or voltage in a transistor? A. Biasing B. Loading C. Load line D. Coupling

A

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°

A

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

A

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

A

2. The voltage gain of a common collector configuration is A. Unity B. Zero C. Very high D. Moderate

A

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

A

214. A common emitter circuit is also called __________ circuit. A. Grounded emitter B. Grounded collector C. Grounded base D. Emitter follower

A

217. What is the ideal maximum voltage gain of a common collector amplifier? A. Unity B. Infinite C. Indeterminate D. Zero

A

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

A

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

A

235. The driver stage usually employs __________ amplifier. A. Class A power B. Class C C. Push-pull D. Class AB

A

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

A

24. What represents common-emitter small signal input resistance? A. hie B. hfe C. hib D. hoe

A

241. When negative current feedback is applied to an amplifier, its output impedance A. increases B. remains unchanged C. decreases D. becomes zero

A

245. Minimum interference with frequency response can be given by A. Direct coupling B. RC coupling C. Transformer coupling D. Instrumentation and control

A

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

A

253. If a transistor amplifier provides a 360° output signal, it is classified as A. class A B. class B C. class C D. class D

A

256. What is the distinguishing feature of a class C amplifier? A. Output is present for less than 180 degrees of the input signal cycle B. Output is present for the entire signal cycle C. Output is present for exactly 180 degrees of the input signal cycle D. Output is present for more than 180 degrees but less than 60 degrees of the input signal cycle

A

261. What is the efficiency of a series-fed class A amplifier? A. 25% B. 50% C. 78.5% D. above 90%

A

266. An amplifier of class AB means its output signal is between the output of class B and A, such that it varies from 180° (class B) to 360° (class A). How about its efficiency? A. Efficiency of class AB is in between the efficiency of class A and B, that is from 25% - 78.5%. B. It is always as efficient as class A (25%). C. It is always as efficient as class B (78.5%) D. The efficiency of class AB is the average of the efficiencies of both class A and class B (25% + 78.5%)/2 = 51.75%

A

29. Which is not a basic BJT amplifier configuration? A. Common-drain B. Common-base C. Common-emitter D. Common-collector

A

542. The has a physical channel between the drain and source. A. d-mosfet B. e-mosfet C. v-mosfet D. none of the above

A

543. All MOSFETs are subject to damage from electrostatic discharge (ESD). A. true B. false

A

548. The capacitor that produces an ac ground is called a A. bypass capacitor B. coupling capacitor C. dc open D. ac open

A

55. An instrument use to measure ones location in terms of coordinates A. GPS B. ILS C. FANS D. GSM

A

555. What is the normalized gain expressed in dB for the cutoff frequencies? A. -3 db B. +3 db C. -6 db D. -20 db

A

560. Most of the electrons in the base of an NPN transistor flow: A. into the collector B. into the emitter C. out of the base lead D. into the base supply

A

570. What is re equal to in terms of h parameters? A. hre / hoe B. (hre + 1) / hoe C. hie - (hre / hoe)(1+ hfe) D. hfe

A

574. 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

A

576. At zero signal condition, a transistor sees load. A. dc B. ac C. both dc and ac D. resistive

A

580. An ideal differential amplifiers common mode rejection ratio is A. infinite B. zero C. unity D. undetermined

A

588. What is the ideal maximum voltage gain of a common collector amplifier? A. unity B. infinite C. indeterminate D. zero

A

59. An amplifier configuration where the input signal is led to the emitter terminal and the output from the collector terminal is called A. Common base B. Common emitter C. Clipper D. Common collector

A

645. An ideal voltage source has A. zero internal resistance B. open circuit voltage equal to the voltage on full load C. terminal voltage in proportion to current D. terminal voltage in proportion to load

A

652. A terminal where three on more branches meet is known as A. node B. terminus C. combination D. anode

A

694. When negative current feedback is applied to an amplifier, its output impedance A. increases B. remains unchanged C. decreases D. becomes zero

A

695. Kirchhoff's current law is applicable to only A. junction in a network B. closed loops in a network C. electric circuits D. electronic circuits

A

698. Minimum interference with frequency response can be given by A. direct coupling B. RC coupling C. transformer coupling D. instrumentation and control

A

703. 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

A

707. A class A amplifier with RC = 3.3 kΩ and RE = 1.2 kΩ has a VCC = 20 V. Find IC(sat). A. 4.4 ma B. 6.1 ma C. 16.7 ma D. 20 ma

A

727. Crossover distortion occurs in amplifiers. A. push-pull B. class a C. class b D. class ab

A

731. coupling is generally employed in power amplifiers A. transformer B. rc C. direct D. impedance

A

752. In class B operation, the current drawn from a single power supply has the form of rectified signal. A. a full-wave B. a half-wave C. both a full-wave and a half-wave D. none of the above

A

759. The greater the power handled by the power transistor, the A. the higher B. the lower C. there is no D. none of the above

A

765. Which of the power amplifiers has the lowest overall efficiency? A. class a B. class b or ab C. class c D. class d

A

770. What is the ratio of the secondary voltage to the primary voltage with the turn ratio in the winding A. n2/n1 B. (n1/n2)2 C. (n1/n2)1/3 D. n1 × n2

A

771. Calculate the effective resistance seen looking into the primary of a 20:1 transformer connected to an 8- Ω load. A. 3.2 kΩ B. 3.0 kΩ C. 2.8 kΩ D. 1.8 kΩ

A

776. Class B operation is provided when the dc bias leaves the transistor biased just off, the transistor turning on when the ac signal is applied. A. true B. false

A

785. Determine what maximum dissipation will be allowed for a 70-W silicon transistor (rated at 25°C) if derating is required above 25°C by a derating factor of 0.6 W/°C at a case temperature of 100°C. A. 25 w B. 30 w C. 35 w D. 40 w

A

122. A pulsating dc applied to power amplifiers causes A. Burning of transistor B. Hum in the circuit C. Excessive forward voltage D. Excessive reverse voltage

B

127. The input impedance of which amplifier depends strongly on load resistance? A. CE B. CC C. CB D. CD

B

128. What capacitors are used in transistor amplifiers? A. Paper B. Electrolytic C. Mica D. Mylar

B

139. What is usually employed at the output stage of an amplifier? A. Class A power amplifier B. Push-pull amplifier C. Pre-amplifier D. Differential amplifier

B

140. Why is it that the size of a power transistor is made considerably large? A. To provide easy handling B. To dissipate more heat C. To simply construction D. To facilitate connections

B

143. An emitter follower is equivalent to A. Common emitter amplifier B. Common collector amplifier C. Common base amplifier D. Hybrid connection

B

146. The term 1+ A β in the expression for gain with negative feedback is known as A. Gain factor B. Sacrifice factor C. Feedback factor D. Quality factor

B

150. When the gain versus frequency curve of a transistor amplifier is not flat, __________ distortion is present. A. Amplitude B. Frequency C. Intermodulation D. Phase

B

157. Class B operation has a maximum possible frequency of ___________ percent. A. 100% B. 78.5% C. 75% D. 2.2%

B

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

B

166. The operating frequency of a Wien-bridge oscillator is given by A. B. C. D.

B

167. Which operation gives the maximum distortion? A. Class A B. Class C C. Class B D. Class AB

B

17. In a class A amplifier, the output signal is A. Distorted B. The same as the input C. Clipped D. Smaller in amplitude than the input

B

170. Class A operation has a maximum possible efficiency of ___________ percent. A. 100% B. 50% C. 75% D. 25%

B

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

B

172. The signal generator generally used in laboratories is ____________ oscillator A. Crystal B. Wien-bridge C. Hartley D. Phase-shift

B

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

B

176. The approximate operating frequency of a phase shift oscillator is given by A. B. C. D.

B

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

B

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

B

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

B

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

B

20. Which power amplifier has the highest collector efficiency? A. Class A B. Class C C. Class B D. Class AB

B

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

B

324. An operational amplifier has a common-mode voltage gain of 10 and a differential-mode voltage gain of 20,000, calculate its common-mode rejection ratio (CMRR). A. 200 B. 2,000 C. 20,000 D. 200,000

B

327. What is the maximum output voltage swing of an op-amp? A. +V to -V (supply voltage) B. +VSAT to -VSAT C. +½V to -½V D. depends on the input signal

B

333. As electronic circuit operates, its operating temperature changes which causes device parameters to change. In op-amps, what do you call the change in input offset voltage due to the change in temperature? A. input differential drift B. input offset voltage drift C. slew rate D. PSRR

B

334. It is known through experiment that the input bias currents at the non-inverting (IB+) and inverting (IB-) inputs of a certain op-amp is 100 nA and 80 nA, respectively. Determine the op-amp's input offset current. A. -20 nA B. 20 nA C. 90 nA D. 180 nA

B

337. Calculate the output offset voltage of an inverting amplifier using op-amp with an input offset current of 10 nA. The circuit is having an input resistance of 10 kΩ and a feedback resistance of 100 kΩ. A. 0.1 mV B. 1.0 mV C. 10.0 mV D. 100.0 mV

B

34. To obtain good gain stability in a negative feedback amplifier, AB is A. Equal to 1 B. Very much greater than 1 C. Less than 1 D. Zero

B

344. The battery representing the input offset voltage in op-amp circuit analysis is connected where? A. between the inverting and ground terminal B. between the non-inverting and ground terminal C. between the inverting and non-inverting terminal D. either B and C above

B

489. A multivibrator having two stable state A. monostable B. bistable C. astable D. unstable

B

49. The input impedance of an amplifier ___________ when negative current feedback is applied. A. Remains unchanged B. Decreases C. Increases D. Becomes zero

B

490. Is also known as Eccles/Jordan circuit A. Monostable multivibrator B. bistable multivibrator C. astable multivibrator D. unstable multivibrator

B

491. Flip-flop is actually a _______ multivibrator. A. Monostable B. bistable C. astable D. unstable

B

52. The driver transformer has center- tapped secondary to provide A. Forward bias to transistors of push-pull circuit B. Two signals 180 degrees out of phase to transistors of push-pull circuit C. Impedance matching D. Two signals in phase with each other

B

529. What is the order of doping, from heavily to lightly doped, for each region? A. base, collector, emitter B. emitter, collector, base C. emitter, base, collector D. collector, emitter, base

B

53. What is the advantage of RC coupling scheme? A. Good impedance matching B. Economy C. High efficiency D. Simplicity

B

531. In what range of voltages is the transistor in the linear region of its operation? A. 0 < vce B. 0.7 < vce < vce(max) C. vce(max) > vce D. none of the above

B

537. A self-biased n-channel JFET has a VD = 6 V. VGS = -3 V. Find the value of VDS. A. -3 v B. -6 v C. 3 v D. 6 v

B

540. The JFET is always operated with the gate-source PN junction-biased. A. forward B. reverse C. all of the above D. none of the above

B

556. Which of the following configurations does not involve the Miller effect capacitance? A. common-emitter B. common-base C. common- collector D. all of the above

B

557. When transistors are used in digital circuits they usually operate in the A. active region B. saturation and cutoff regions C. breakdown region D. linear region

B

56. Transformer coupling is used for _________ amplification. A. Current B. Power C. Voltage D. Signal

B

561. The BJT is a device. The FET is a device. A. bipolar, bipolar B. bipolar, unipolar C. unipolar, bipolar D. unipolar, unipolar

B

562. The Bode plot is applicable to A. all phase network B. minimum phase network C. maximum phase network D. lag lead network

B

568. A common-emitter amplifier has voltage gain, current gain, power gain, and input impedance. A. high, low, high, low B. high, high, high, low C. high, high, high, high D. low, low, low, high

B

569. To analyze the common-emitter amplifier, what must be done to determine the dc equivalent circuit? A. leave circuit unchanged B. replace coupling and bypass capacitors with opens C. replace coupling and bypass capacitors with shorts D. replace vcc with ground

B

571. The advantage that a Sziklai pair has over a Darlington pair is A. higher current gain. B. less input voltage is needed to turn it on. C. higher input impedance. D. higher voltage gain.

B

575. 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

B

578. The current gain of an emitter follower is A. equal to 1 B. greater than 1 C. less than 1 D. zero

B

579. 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

B

586. 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

B

589. 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

B

593. 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

B

598. 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

B

599. A class A power amplifier uses transistor(s). A. two B. one C. three D. four

B

603. Find the voltage drop developed across a D' Arsonval meter movement having an internal resistance of 1 kΩ and a full deflection current of 150 µA. A. 150 µv B. 150 mv C. 150 v D. 200 mv

B

607. The push-pull circuit must use operation. A. class a B. class b C. class c D. class ab

B

610. The output transformer used in a power amplifier is a/an ______ transformer A. 1:1 ratio B. step-down C. step-up D. isolation

B

611. An emitter follower has a voltage gain that is A. much less than one B. approximately equal to one C. greater than one D. zero

B

612. The input impedance of the base of an emitter follower is usually A. low B. high C. shorted to ground D. open

B

666. A family of logic devices designed for extremely high speed applications is called A. nmos. B. ecl. C. pmos. D. ttl.

B

69. To amplify dc signals, multistage amplifier uses what coupling? A. RC B. Direct C. Transformer D. Resistor

B

790. The theorem is a way to determine the currents and voltages present in a circuit that has multiple sources. A. norton B. super position C. thevenin D. maximum power transfer

B

104. Negative feedback is employed in A. Oscillators B. Rectifiers C. Amplifiers D. Receivers

C

105. The gain of an amplifier is expressed in dB unit because A. It is a simple unit B. Calculations become easy C. Human ear response is logarithmic D. It is the most appropriate unit

C

107. In a multistage amplifier, if the stages have R and C component only, ___________ operation is apparent. A. Class B B. Class C C. Class A D. Class AB

C

109. What is the main consideration in the output stage of an amplifier? A. Power output B. Voltage gain C. Power gain D. Current gain

C

118. What is the ratio of output to input impedance of a CE amplifier? A. Very low B. Very high C. Moderate D. Approximately 1

C

12. The coupling capacitor Cc must be large enough to ___________ in an RC coupling scheme. A. Pass dc between the stages B. Dissipate high power C. Prevent attenuation of low frequency D. Prevent attenuation of high frequency

C

125. In phase-shift oscillator, what are the frequency determining elements? A. L and C B. R, L and C C. R and C D. R and L

C

130. What type of feedback is used in Wien bridge oscillator? A. Positive B. Negative C. Both positive and negative D. Either positive or negative

C

132. What is the most costly coupling? A. RC coupling B. Direct C. Transformer D. Inductive

C

133. When the output of an amplifier is 10V and 100mV from the output is fed back to the input, feedback factor is A. 10 B. 0.1 C. 0.01 D. 0.15

C

14. An oscillator produces ____________ oscillations. A. Damped B. Modulated C. Undamped D. Sinusoidal

C

144. The crystal oscillator frequency is very stable due to ___________ of the crystal. A. Rigidity B. Ductility C. High Q D. Low Q

C

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

C

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

C

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

C

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

C

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

C

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

C

181. The power input to a power amplifier is __________ quantity. A. ac B. Pulsating dc C. dc D. sinusoidal

C

187. The number of transistor in a single stage amplifier is A. Two B. Three C. One D. Four

C

188. Series current negative feedback occurs when the feedback voltage is proportional to the output A. Voltage B. Impedance C. Current D. Power

C

194. What is the desired input impedance of a transistor? A. Low B. Very low C. High D. Very high

C

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

C

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

C

201. What is the device in a transistor oscillator? A. LC tank circuit B. Biasing circuit C. Transistor D. Feedback circuit

C

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

C

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

C

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

C

220. The capacitors are considered ___________ in the ac equivalent circuit of a transistor amplifier. A. Open B. Partially open C. Short D. Partially short

C

221. For highest power gain, what configuration is used? A. CC B. CB C. CE D. CS

C

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

C

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

C

229. What is the maximum collector efficiency of a resistance loaded class A power amplifier? A. 50% B. 78.5% C. 25% D. 30%

C

231. Class C amplifiers are used as A. AF amplifiers B. Small signal amplifiers C. RF amplifiers D. IF amplifiers

C

234. Comparatively, power amplifier has _________ β. A. Large B. Very large C. Small D. Very small

C

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

C

240. Transformer coupling can be used in ___________ amplifiers A. Only power B. Only voltage C. Either power or voltage D. Neither power nor voltage

C

242. The quiescent current of a FET amplifier is A. IDS B. id C. ID D. Id

C

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

C

251. What do you call an amplifier which has an output current flowing during the whole input current cycle? A. class AB amplifier B. class B amplifier C. class A amplifier D. class C amplifier

C

257. A full 360° sine-wave signal is applied as an input to an unknown class of amplifier, if the output delivers only a pulse of less than 180°, of what class does this amplifier belongs? A. class AB B. class B C. class C D. class D

C

258. Which class of amplifiers that is intended for pulse operation? A. class B B. class C C. class D D. class S

C

263. Class B amplifiers deliver an output signal of 180° and have a maximum efficiency of A. 50% B. 68.5% C. 78.55 D. above 90%

C

279. A push-pull amplifier that uses either npn or pnp as its final stage. The circuit configuration looks like the complementary-symmetry. A. transformer-coupled push -pull amplifier B. complementary-symmetry amplifier C. quasi-complementary push-pull amplifier D. feed-back pair amplifier

C

287. Which of the following refers to the gain of a circuit? A. Input quantity of an amplifier divided by the output quantity. B. The difference between the input voltage and the output voltage of a circuit. C. The ratio of the output quantity to input quantity of an amplifier. D. The total increase in output quality over the input quantity of an amplifier.

C

288. The overall gain of an amplifier in cascade is A. the sum B. the average of each C. the product D. 100% the sum

C

289. If three amplifiers with a gain of 8 each are in cascade, how much is the overall gain? A. 72 B. 24 C. 512 D. 8

C

291. A direct-coupled two-stage transistor configuration wherein the output of the first transistor is directly coupled and amplified by the second transistor. This configuration gives a very high current gain. A. cascade configuration B. cascode configuration C. darlington configuration D. feed-back pair

C

295. Transistor configuration known to have a super-beta (β2). A. cascade B. cascode C. darlington D. differential

C

296. What is the approximate threshold voltage between the base-emitter junction of a silicon darlington transistor? A. 0.3 V B. 0.6 V C. 1.6 V D. 3.0 V

C

482. What determines the resonant frequency of a crystal? A. external components B. the temperature of the crystal C. the size and thickness of the crystal material D. the hermitic seal

C

492. Considered as a free-running multivibrator A. monostable B. bistable C. astable D. unstable

C

494. Filter that is characterized by ripple at the passband and fast roll-off rate a. Butterworth b. Elliptic c. Chebyshev d. Notch

C

495. An LC circuit resonates at 2000 kHz and has a Q of 100. Find the lower and upper cut-off frequencies. a. 1980 kHz, 2020 kHz b. 1950 kHz, 2050 kHz c. 1990 kHz, 2010 kHz d. 1900 kHz, 2100 kHz

C

498. What happens to the output resistance of an amplifier employing voltage-shunt feedback? a. It is increased b. It remains the same c. It is decreased d. Equals infinity

C

500. _____ is the progressive decay with time in the amplitude of the free oscillation in a circuit. a. Decrement b. Pulse decay time c. Damping d. Dancing

C

503. The barrier potential across each silicon depletion layer is A. 0 v B. 0.3 v C. 0.7 v D. 1 v

C

509. When a transistor is used as a switch, it is stable in which two distinct regions? A. saturation and active B. active and cutoff C. saturation and cutoff D. none of the above

C

51. A type of oscillator wherein the frequency is determined by the charge and discharge of resistor-capacitor networks used in conjunction with amplifiers or similar devices. A. Sine wave oscillator B. Beta generating circuit C. Relaxation oscillator D. Simply an oscillator

C

512. The magnitude of dark current in a phototransistor usually falls in what range? A. ma B. ma C. na D. pa

C

514. When not in use, MOSFET pins are kept at the same potential through the use of: A. shipping foil B. nonconductive foam C. conductive foam D. a wrist strap

C

516. A very simple bias for a D-MOSFET is called: A. self biasing B. gate biasing C. zero biasing D. voltage- divider biasing

C

522. When a transistor is used as a switch, it is stable in which two distinct regions? A. saturation and active B. active and cutoff C. saturation and cutoff D. none of the above

C

524. A BJT has an IB of 50 µA and a βDC of 75; IC is: A. 375 ma B. 37.5 ma C. 3.75 ma D. 0.375 ma

C

526. For normal operation of a PNP BJT, the base must be with respect to the emitter and with respect to the collector. A. positive, negative B. positive, positive C. negative, positive D. negative, negative

C

528. A 35 mV signal is applied to the base of a properly biased transistor with an r'e = 8 Ω and RC = 1 kΩ. The output signal voltage at the collector is: A. 3.5 v B. 28.57 v C. 4.375 v D. 4.375 mv

C

532. What does DC vary with? A. ic B. °c C. both ic and °c D. ic', but not °c

C

535. The magnitude of dark current in a phototransistor usually falls in what range? A. ma B. μa C. na D. pa

C

536. Which of the following devices has the highest input resistance? A. diode B. jfet C. mosfet D. bipolar junction transistor

C

544. Midpoint bias for a D-MOSFET is ID = , obtained by setting VGS = 0. A. idss /2 B. idss /3.4 C. idss D. None of these

C

564. The dc emitter current of a transistor is 8 mA. What is the value of re? A. 320 Ω B. 13.3 kΩ C. 3.125 Ω D. 5.75 Ω

C

565. An emitter-follower amplifier has an input impedance of 107 kΩ. The input signal is 12 mV. The approximate output voltage is (common-collector) A. 8.92 v B. 112 mv C. 12 mv D. 8.9 mv

C

566. You have a need to apply an amplifier with a very high power gain. Which of the following would you choose? A. common-collector B. common-base C. common-emitter D. emitter- follower

C

57. What is the typical value of coupling capacitor Cc in RC coupling? A. About 100 pF B. About 0.1 µF C. About 10 µF D. About 0.01 µF

C

572. What is the device in a transistor oscillator? A. LC tank circuit B. biasing circuit C. transistor D. feedback circuit

C

577. What is the gain of an amplifier with negative feedback if the feedback factor is 0.01? A. 10 B. 1000 C. 100 D. 500

C

58. An electronic transfer from one stage to the next is termed as ____________. A. Doping B. Mixing C. Coupling D. Connecting

C

582. 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

C

584. 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

C

591. The capacitors are considered in the ac equivalent circuit of a transistor amplifier. A. open B. partially open C. short D. partially short

C

592. For highest power gain, what configuration is used? A. cc B. cb C. ce D. cs

C

596. 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

C

597. 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

C

6. A transistor amplifier has high output impedance because A. Emitter is heavily doped B. Collector is wider than emitter or base C. Collector has reverse bias D. Emitter has forward bias

C

600. What is the maximum collector efficiency of a resistance loaded class A power amplifier? A. 50% B. 78.50% C. 25% D. 30%

C

602. Class C amplifiers are used as A. af amplifiers B. small signal amplifiers C. rf amplifiers D. if amplifiers

C

605. Comparatively, power amplifier has β. A. large B. very large C. small D. very small

C

609. 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

C

614. The output voltage of an emitter follower is across the A. emitter diode B. dc collector resistor C. load resistor D. emitter diode and external ac emitter resistance

C

615. The differential amplifier has A. one input and one output B. two inputs and two outputs C. two inputs and one output D. one input and two outputs

C

617. Which factor does not affect CMOS loading? A. charging time associated with the output resistance of the driving gate B. discharging time associated with the output resistance of the driving gate C. output capacitance of the load gates D. input capacitance of the load gates

C

623. The most desirable feature of transformer coupling is its A. higher voltage gain B. wide frequency range C. ability to provide impedance matching between stages D. ability to eliminate hum from the output

C

625. One of the advantages of a Darlington pair is that it has enormous ______ transformation capacity. A. voltage B. current C. impedance D. power

C

656. A linear resistor having 0 < R < °o is a A. current controlled resistor B. voltage-controlled resistor C. both current controlled and voltage-controlled resistor D. none of the above

C

661. The superposition theorem requires as many circuits to be solved as there are A. sources, nodes and meshes B. sources and nodes C. sources D. nodes

C

676. The abbreviated designation for input current with a LOW input is A. VIH. B. IIH. C. IIL. D. IOL.

C

679. The abbreviated designator for a LOW output voltage is A. VOH. B. VIL. C. VOL. D. VIH.

C

681. Typical TTL HIGH level output voltage is A. 0.3 v. B. 5.0 v. C. 3.4 v. D. 4.8 v.

C

70. What oscillator is used on order to produce frequencies in the microwave region? A. Wien bridge B. Hartley C. Klystron D. Crystal

C

700. 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

C

704. Which amplifier is commonly used as a frequency multiplier? A. class A B. class B C. class C D. all of the above

C

706. You have an application for a power amplifier to operate on FM radio frequencies. The most likely choice would be a ______ amplifier. A. class A B. class B C. class C D. class AB

C

708. A class C amplifier has a tank circuit in the output. The amplifier is conducting only 28°. The output voltage is ____. A. 0 v. B. a dc value equal to vcc. C. a sine wave. D. a square wave with a frequency determined by the tank.

C

714. Which class of amplifier operates in the linear region for only a small part of the input cycle? A. a B. b C. c D. ab

C

716. The principal advantage(s) of BJTs over MOSFETs is (are) that A. voltage drop across the transistor is important. B. they are not as prone to esd. C. both of the above D. none of the above

C

717. The class amplifier is biased below cutoff. A. a B. ab C. b D. c

C

72. What coupling provides maximum voltage gain? A. RC B. Direct C. Transformer D. Resistor

C

720. Class-C amplifiers are almost always A. transformer- coupled between stages B. operated at audio frequencies C. tuned rf amplifiers D. wideband

C

721. Heat sinks reduce the A. transistor power B. ambient temperature C. junction temperature D. collector current

C

722. Which type of power amplifier is biased for operation at less than 180° of the cycle? A. class a B. class b or ab C. class c D. class d

C

73. The gain of an amplifier __________ when negative feedback is added. A. Increases B. Remains unchanged C. Reduces D. Becomes infinite

C

733. Class power amplifier has the highest collector efficiency A. c B. a C. b D. ab

C

734. Power amplifiers handle signals compare to voltage amplifiers. A. small B. very small C. large D. none of the above

C

737. The output transformer used in a power amplifier is a ______ transformer. A. 1:1 ratio B. step-up C. step-down D. none of the above

C

754. transistors can be used to build a class B amplifier. A. NPN and PNP B. NMOS and PMOS C. both NPN and PNP or NMOS and PMOS D. none of the above

C

762. A power amplifier is limited to use at one fixed frequency. A. class a B. class b or ab C. class c D. class d

C

763. By how much does the output signal vary for a class AB power amplifier? A. 360° B. 180° C. between 180° and 360° D. less than 180°

C

769. Categorize the power efficiency of each class of amplifier, from worst to best. A. a, b, ab, d B. a, ab, d, b C. a, ab, b, d

C

77. What class of operation is used where a portion of a signal only is required, such as the synchronizing pulse separator of a television receiver? A. Class A B. Class B C. Class AB D. Class C

C

775. How many transistors must be used in a class B power amplifier to obtain the output for the full cycle of the signal? A. 0 B. 1 C. 2 D. 3

C

777. Calculate the efficiency of a class B amplifier for a supply voltage of VCC = 20 V with peak output voltage of VL(p) = 18 V. Assume RL = 16 Ω. A. 78.54% B. 75% C. 70.69% D. 50%

C

783. What is the maximum temperature rating for silicon power transistors? A. 50° to 80° B. 100° to 110° C. 150° to 200° D. 250° to 300°

C

784. Which of the power amplifiers is not intended primarily for large- signal or power amplification? A. class a B. class b or ab C. class c D. class d

C

120. The frequency stability of the oscillator output is maximum in ____________ oscillator. A. LC B. Crystal C. Phase-shift D. Wien bridge

D

626. Bootstrapping is used in emitter follower configurations to A. stabilize the voltage gain against process variations B. increase current gain C. reduce the output resistance D. increase the input resistance

D

418. For a class B amplifier, the operating point or Q-point is set at A. the top of the load line B. saturation C. the center D. cutoff

D

424. Transistor arrangement that operates like a darlington but uses a combination of pnp and npn transistors instead of both npn. A. differential B. common C. cascode D. feedback pair

D

430. In the active region, the collector-base junction is ________, while the base-emitter junction is ________. A. forward and forward-biased B. forward and reverse-biased C. reverse and reverse biased D. reverse and forward-biased

D

431. In dc biasing, it means quiet, still, inactive A. passive B. quench C. static D. quiescent

D

434. For a common-emitter transistor configuration, the hybrid parameter hfe stands for forward transfer current ratio. This parameter is approximately equal to A. HFE B. βac C. β D. all of these

D

478. A unity-gain summing amplifier has three inputs, V1 = 1.0 mV, V2 = 1.5 mV, and V3 = 2.5 mV, calculate the total output voltage. A. 2.5 mV B. 3.5 mV C. 4.0 mV D. 5.0 mV

D

487. Monostable multivibrator is also known as A. one shot B. single shot C. direct shot D. one shot or single shot

D

488. What determines the pulse time in a monostable multivibrator? A. resistor combinations B. capacitor combinations C. inductor combinations D. resistor and capacitor combinations

D

508. The extremely high input impedance of a MOSFET is primarily due to the A. absence of its channel B. negative gate- source voltage C. depletion of current carriers D. extremely small leakage current of its gate capacitor

D

510. The term BJT is short for A. base junction transistor B. binary junction transistor C. both junction transistor D. bipolar junction transistor

D

515. A MOSFET has how many terminals? A. 2 or 3 B. 3 C. 4 D. 3 or 4

D

521. The dc load line on a family of collector characteristic curves of a transistor shows the A. saturation region. B. cutoff region. C. active region. D. all of the above

D

523. The value of βDC A. is fixed for any particular transistor. B. varies with temperature. C. varies with ic. D. varies with temperature and ic.

D

525. A certain transistor has IC = 15 mA and IB = 167 µA; βDC is: A. 15 B. 167 C. 0.011 D. 90

D

533. What is (are) common fault(s) in a BJT-based circuit? A. pens or shorts internal to the transistor B. open bias resistor(s) C. external opens and shorts on the circuit board D. all of the above

D

534. What is (are) general-purpose/small-signal transistors case type(s)? A. to-18 B. to-92 C. to-39 D. all of the above

D

539. A JFET data sheet specifies VGS(off) = -10 V and IDSS = 8 mA. Find the value of ID when VGS = -3 V. A. 2 ma B. 1.4 ma C. 4.8 ma D. 3.92 ma

D

54. A type of filter which is having a single continuous transmission band with neither the upper nor the lower cut-off frequencies being zero or infinite is called A. Band stop filter B. Low pass filter C. High pass filter D. Band pass filter

D

573. When the collector supply is 5 V, then collector cut off voltage under dc condition is A. 20 v B. 10 v C. 2.5 v D. 5 v

D

581. An open fuse circuit has a resistance equal to A. zero B. unity C. at least 100 Ω atstandard D. infinity

D

587. 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 Vrms A. 5% B. 10% C. 50% D. 6%

D

594. 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

D

601. What is the maximum collector efficiency of a transformer coupled class A power amplifier? A. 30% B. 80% C. 45% D. 50%

D

613. The ac base voltage of an emitter follower is across the A. emitter diode B. dc emitter resistor C. load resistor D. emitter diode and external ac emitter resistance

D

616. The differential amplifier produces outputs that are A. common mode B. in-phase with the input voltages C. the sum of the two input voltages D. the difference of the two input voltages

D

100. In the initial stages of a multistage amplifier, ____________ coupling is used. A. Link B. RC C. Transformer D. Impedance

B

358. The reduction of op-amps gain due to increasing operating frequency. A. Cutoff B. roll-off C. diminishing factor D. reduction step

B

419. A push-pull amplifier that uses npn and pnp transistors to amplify the positive and negative cycles respectively. A. transformer-coupled push -pull amplifier B. complementary-symmetry amplifier C. quasi-complementary push-pull amplifier D. transformer-coupled class A amplifier

B

422. A two-stage transistor amplifier in which the output collector of the first stage provides input to the emitter of the second stage. The final output is then taken from the collector of the second stage. A. cascade configuration B. cascode configuration C. quasi-complementary D. complementary amplifier

B

427. The region or area in a transistor that is heavily doped A. at the junction B. emitter C. collector D. base

B

475. An active integrator uses an op-amp, what is its feedback element? A. Resistor B. capacitor C. inductor D. RC network

B

604. 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

B

622. The decibel gain of a cascaded amplifier equals to A. product of individual gains B. sum of individual gains C. ration of stage gains D. product of voltage and current gains

B

624. A transformer coupled amplifier would give A. maximum voltage gain B. impedance matching C. maximum current gain D. larger bandwidth

B

627. To determine the polarity of the voltage drop across a resistor, it is necessary to know A. value of current through the resistor B. direction of current through the resistor C. value of resistor D. e.m.fs. in the circuit

B

636. For high efficiency of transfer of power, internal resistance of the source should be A. equal to the load resistance B. less than the load resistance C. more than the load resistance D. none of the above

B

651. Between the branch voltages of a loop the Kirchhoff's voltage law imposes A. non-linear constraints B. linear constraints C. no constraints D. none of the above

B

655. A closed path made by several branches of the network is known as A. branch B. loop C. circuit D. junction

B

662. Which of the following is a concern when using CMOS type devices? A. mechanical shock B. electrostatic discharge C. fan out D. under voltage

B

663. Which of the following is not a solution to interface problems between CMOS and TTL? A. pull-up resistor B. pull-down resistor C. level-shifter D. buffer

B

665. The output current for a LOW output is called a(n) A. exit current. B. sink current. C. ground current. D. fan-out.

B

673. The maximum current for a HIGH output on a standard TTL gate is A. -10 µa. B. -400 µa. C. -1 µa. D. -10 ma.

B

680. The lower transistor of a totem-pole output is saturated when the gate output is A. high. B. low. C. malfunctioning. D. over driven.

B

682. The standard 74XX TTL IC family was originally developed in the A. 1970s. B. 1960s. C. 1950s. D. 1940s.

B

683. The minimum output voltage recognized as a HIGH by a TTL gate is A. 0.8 v. B. 2.4 v. C. 5.0 v. D. 2.0 v.

B

691. An amplifier without feedback has a voltage gain of 50, input resistance is 1 KΩ & Output resistance of 2. 5 KΩ.The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is A. 1/11 kΩ B. 1/5 kΩ C. 5 kΩ D. 11 kΩ

B

696. The total decibel voltage gain of two cascaded voltage amplifiers where individual voltage gains are 10 and 100 is A. 20 B. 60 C. 800 D. 1000

B

701. 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 20 mV 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

B

710. The Q-point is at cutoff for class operation. A. a B. b C. c D. ab

B

718. For Class-B operation, the collector current flows for A. the whole cycle B. half the cycle C. less than half a cycle D. less than a quarter of a cycle

B

719. Transformer coupling is an example of A. direct coupling B. ac coupling C. dc coupling D. impedance coupling

B

726. The output of a class-B amplifier A. is distortion free B. consists of positive half cycle only C. is like the output of a full wave rectifier D. comprises short duration current pulses

B

735. In class B operation, at what fraction of VCC should the level of VL(p) be to achieve the maximum power dissipated by the output transistor? A. 0.5 B. 0.636 C. 0.707 D. 1

B

550. A common-gate amplifier is similar in configuration to which BJT amplifier? A. common-emitter B. common- collector C. common-base D. emitter- follower

C

380. A unity-gain summing amplifier has three inputs, V1 = 1.0 mV, V2 = 1.5 mV, and V3 = 2.5 mV, calculate the total output voltage. A. 2.5 mV B. 3.5 mV C. 4.0 mV D. 5.0 mV

D

637. Efficiency of power transfer when maximum transfer of power c A. 100% B. 80% C. 75% D. 50%

D

649. Mill man's theorem yields A. equivalent resistance B. equivalent impedance C. equivalent voltage source D. equivalent voltage or current source

D

650. The superposition theorem is applicable to A. voltage only B. current "only C. both current and voltage D. current voltage and power

D

709. In practice, the efficiency of a capacitively coupled class A amplifier is about ___%. A. 25 B. 40 C. 70 D. 10

D

800. Maximum power output is obtained from a network when the load resistance is equal to the output resistance of the network as seen from the terminals of the load". The above statement is associated with A. mill man's theorem B. thevenin's theorem C. superposition theorem D. maximum power transfer theorem

D

743. Class D operation can achieve power efficiency of over . A. 90% B. 78.50% C. 50% D. 25%

A

75. What class of operation is used for general amplification where no distortion can be tolerated? A. Class A B. Class B C. Class AB D. Class C

A

750. A class A amplifier dissipates power when the load is drawing maximum power from the circuit. A. the least B. about the same C. the most D. none of the above

A

79. Why is transformer coupling provides high frequency? A. DC resistance is low B. Collector voltage is stepped up C. Collector voltage is stepped down D. AC resistance is high

A

792. Kirchhoff's current law is applicable to only A. junction in a network B. closed loops in a network C. electric circuits D. electronic circuits

A

797. Mesh analysis is applicable for A. planar networks B. non-planar networks C. both a & b D. electric networks

A

799. Kirchhoff's current law is applicable only to A. junction in a network B. closed loops in a network C. electric circuits D. electronic circuits

A

81. Class C operation can have _____________ percent efficiency. A. 100% B. 78.5% C. 50% D. 70%

A

618. Which transistor element is used in CMOS logic? A. fet B. mosfet C. bipolar D. unijunction

B

62. What is the basic purpose of applying negative feedback to an amplifier? A. To increase gain B. To reduce distortion C. To keep the temperature within limits D. To increase input signal

B

620. What is the effect of cascading amplifier stages? A. increase in the voltage gain and increase in the bandwidth B. increase in the voltage gain and reduction in the bandwidth C. decrease in the voltage gain and increase in the bandwidth D. increase in the voltage gain and reduction in the bandwidth

B

641. The circuit whose properties are same in either direction is known as A. unilateral circuit B. bilateral circuit C. irreversible circuit D. reversible circuit

B

670. The difference between VOH and VIH voltages is known as A. input margin. B. noise margin. C. output differential. D. input level.

B

71. Practically, the voltage gain of an amplifier is expressed A. In volts unit B. In dB unit C. As an absolute value D. As a whole number

B

724. The Q-point is at cutoff for class operation. A. a B. b C. c D. ab

B

730. The output stage of a multistage amplifier is also called A. mixer stage B. power stage C. detector stage D. f stage

B

547. In a bypass circuit, the top of a capacitor is A. an open B. a short C. an ac ground D. a mechanical ground

C

551. A common-source amplifier is similar in configuration to which BJT amplifier? A. common-base B. common- collector C. common-emitter D. emitter- follower

C

552. When transistors are used in digital circuits they usually operate in the A. active region B. breakdown region C. saturation and cutoff regions D. linear region

C

563. For any inverting amplifier, the impedance capacitance will be ______ by a Miller effect capacitance sensitive to the gain of the amplifier and the interelectrode capacitance. A. unaffected B. increased C. decreased D. none of the above

C

567. What is the most important r parameter for amplifier analysis? A. rb′ B. rc′ C. re′ D. none of the above

C

685. The minimum input voltage recognized as a HIGH by a TTL gate is A. 0.8 v. B. 2.4 v. C. 2.0 v. D. 5.0 v

C

686. Which of the following digital IC logic families is most susceptible to static discharge? A. rtl B. ecl C. mos D. ttl

C

693. Transformer coupling can be used in amplifiers A. only power B. only voltage C. either power or voltage D. neither power nor voltage

C

744. The beta of a power transistor is generally . A. more than 200 B. 100 to 200 C. less than 100 D. none of these

C

370. When an op-amp is used as a comparator, the output voltage would be +VSAT if A. V+ > V- B. V- > V+ C. V- = V+ D. V- and V+ are both zero

A

305. An amplifier whose output is proportional to the difference between the voltages applied to its two inputs. A. differential amplifier B. differencing C. delta amp D. cascode-amp

A

313. The stage followed by the output complementary in op-amps functional block diagram. A. level shifter B. phase shifter C. current mirror D. polarizer

A

314. What is the purpose of a level shifter in op-amps? A. to set and/or adjust the output voltage to zero when the input signal is zero B. to set and/or adjust the input offset voltage to zero C. to shift the input offset current to zero D. all of the above

A

315. Primarily, op-amps are operated with bipolar power supply, however, we can also use single polarity power supply by A. generating a reference voltage above ground. B. "floating" the negative supply terminal (V-) of the op-amp. C. simply connecting the negative supply terminal (V-) of the op-amp to ground. D. isolating the negative supply terminal (V-) by a capacitor.

A

317. When the same signal is applied to both inverting and non-inverting input terminals of an ideal op-amp, the output voltage would be A. zero (0) V B. +VSAT C. -VSAT D. offset voltage

A

329. The current needed at the input of an op-amp to operate it normally A. input bias current B. input offset current C. input threshold current D. input holding current

A

33. What is the time taken by the electrons or holes to pass from the emitter to the collector? A. Transit time B. Recombination C. Transient time D. Duty cycle

A

340. How will you minimize the output offset voltage due to the input offset current of an op-amp? A. by installing a bias-current-compensating resistor B. by increasing the value of the feedback resistor C. by decreasing the value of the input resistor D. B and C above

A

343. In op-amp analysis, the input offset voltage is represented by A. a battery B. a signal generator C. Thevenin's voltage source D. Norton's current source

A

346. How can we minimize the effect of the input offset current and input offset voltage at the output offset voltage? A. by making the feedback resistance small B. by making the feedback resistance large C. by making the input resistance small D. by making the input resistance large

A

395. The most popular op-amp packages are the metal can, 8-pin DIP, and the SMT. Which of these corresponds to TO-99? A. metal can B. 8-pin DIP C. SMT D. all of the above

A

407. A self-excited oscillator in which the tank is divided into input and feedback portions by an inductive voltage divider or a tapped coil. A. Hartley oscillator B. Colpitts oscillator C. Relaxation oscillator D. Klystron oscillator

A

408. A circuit usually containing two transistors or tubes in an RC-coupled amplifier, the two active devices switch each other alternately on and off. A. Multivibrator B. Signal generator C. Oscillator D. Thyristor

A

42. RC coupling is used for _____________ amplification. A. Voltage B. Current C. Signal D. Power

A

421. A multistage transistor amplifier arranged in a conventional series manner, the output of one stage is forward-coupled to the next stage. A. cascaded amplifier B. cascoded amplifier C. darlington configuration D. feed-back pair configuration

A

429. It is applied to any system where levels have reached their maximum values A. saturation B. active C. cutoff D. quiescent point

A

439. What do you call the area in a JFET where current passes as it flows from source (S) to drain (D). A. channel B. substrate C. depletion D. drift

A

440. In MOSFET, it is the foundation upon which the device will be constructed and is formed from a silicon base A. substrate B. slab C. source D. base

A

441. What is network node dedicated to interfacing between the network and one or more printers? a. Print server b. Lay-out Server c. Tune server d. All of these

A

443. A type of oscillator which uses an amplifier circuit that introduces 1800 phase shift a. RC Phase Shift Oscillator b. Wien Bridge Oscillator c. Hartley Oscillator d. Armstrong Oscillator

A

445. The measure of how "pure" or "real" an inductor is. The higher its value in an inductor, the fewer losses there are. a. Q-factor b. Beta Factor c. Alpha Factor d. K-factor

A

446. This can be defined as the ratio of output d.c. power available at the load to the power rating (Volt Ampere) of the transformer used in the rectifier circuit a. Transformer Utilization Factor b. Transformer Form Factor c. Transformer Load Voltage Factor d. Transformer Working Factor

A

45. When the non-linear distortion in an amplifier is D without feedback, with negative voltage feedback it will be A. D/ 1+ A β B. 1+ A β / D C. D (1+A β) D. D (1-A β)

A

451. An amplifier basically constructed from two transistors and whose output is proportional to the difference between the voltages applied to its two inputs. A. differential amplifier B. cascode amplifier C. complementary amplifier D. quasi-complementary amplifier

A

74. Feedback factor is always A. Less than 1 B. Equal to 1 C. More than 1 D. Zero

A

452. It is a diagnostic application or device that a network administrator can purchase and install on a network workstations or attach to the network media to monitor and capture dat packets for subsequent analysis.. a. Sniffer b. Splatter c. Clipper d. Clamper

A

454. When the same signal is applied to both inverting and non-inverting input terminals of an ideal op-amp, the output voltage would be A. zero (0) V B. +VSAT C. -VSAT D. offset voltage

A

595. 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

A

60. If the noise factor of an ideal amplifier expressed in dB, then it is A. 0 B. 0.1 C. 1 D. 10

A

606. The driver stage usually employs amplifier. A. class a power B. class c C. push-pull D. class ab

A

608. 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

A

61. A feedback circuit is ______________ frequency A. Independent of B. Strongly dependent on C. Moderately dependent on D. Relatively dependent on

A

630. Which of the following is non-linear circuit parameter? A. inductance B. condenser C. wire wound resistor D. transistor

A

639. For maximum transfer of power, internal resistance of the source should be A. equal to load resistance B. less than the load resistance C. greater than the load resistance D. none of the above

A

64. Which frequency produces the highest noise factor? A. 10 kHz B. 500 Hz C. 1 kHz D. 100 Hz

A

640. If the energy is supplied from a source, whose resistance is 1 ohm, to a load of 100 ohms the source will be A. a voltage source B. a current source C. both of above D. none of the above

A

642. In a series parallel circuit, any two resistances in the same current path must be in A. series with each other B. parallel with each other C. series with the voltage source. D. parallel with the voltage source

A

648. Application of Norton's theorem to a circuit yields A. equivalent current source and impedance in series B. equivalent current source and impedance in parallel C. equivalent impedance D. equivalent current source

A

66. The operating point is generally located at ______________ of dc load line in class A operation A. The middle B. Saturation point C. Cut off point D. End point

A

660. The number of independent equations to solve a network is equal to A. the number of chords B. the number of branches C. sum of the number of branches and chords D. sum of number of branches, chords and nodes

A

664. Which of the following is not a common logic family used today? A. rtl B. ecl C. ttl D. cmos

A

668. The lower transistor of a totem-pole output is OFF when the gate output is A. high. B. malfunctioning. C. low. D. over driven.

A

67. Which of the following describes a common collector amplifier? A. Low voltage gain B. Low current gain C. Low power gain D. Low input resistance

A

672. The major advantage of TTL logic circuits over CMOS is A. lower propagation delay. B. the ability to output higher voltages. C. more modern design. D. very low power consumption

A

675. The major advantage of CMOS logic circuits over TTL is A. very low power consumption. B. the ability to produce several output voltage levels. C. lower propagation delay. D. much higher propagation delay.

A

68. The general characteristics of a common base amplifier are A. High voltage gain, low current gain, high power gain and very low input resistance B. High voltage, high current gain, high power gain and low input resistance C. Low voltage gain, high current gain, very high power gain and low input resistance D. None of the choices

A

684. An open-collector TTL gate A. can sink current but cannot source current. B. can source current but cannot sink current. C. cannot source or sink current. D. can sink more current than a standard TTL gate.

A

688. The time it takes for an input signal to pass through internal circuitry and generate the appropriate output effect is known as A. propagation delay B. rise time C. fan-out D. fall time

A

689. In a common emitter, unbypassed resister provides A. voltage shunt feedback B. current series feedback C. negative voltage D. positive current feedback

A

690. Negative feedback in an amplifier A. reduces gain B. increase frequency & phase distortion C. reduces bandwidth D. increases noise

A

85. The __________ the voltage regulation, the better the operation of the voltage supply circuit. A. Smaller B. Bigger C. Moderate D. Biggest

A

9. What linear circuit compares two input signals and provides a digital level output depending on the relationship of the input signals? A. Comaparator B. Controller C. Compressor D. Switch

A

92. The frequency of oscillation is __________ L and C in an LC oscillator. A. Inversely proportional to square root of B. Directly proportional to C. Independent of the values of D. Proportional to square of

A

93. An oscillator employs ____________ feedback. A. Positive B. Negative C. Both positive and negative D. Neither positive nor negative

A

102. If Av is 50 Ai is 200, what is the power gain of a common emitter amplifier? A. 1,000 B. 10,000 C. 100 D. 100,000

B

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 20 mV 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. 6 mV p-p

B

254. An amplifier that delivers an output signal of 180° only. A. class A B. class B C. class AB D. class D

B

264. Transistorized class C power amplifiers will usually have an efficiency of A. 25% B. 33% C. 50% D. 78.5%

B

356. The frequency at which the open-loop gain of an op-amp is 0.707 times its value at very low frequency A. threshold frequency B. break frequency C. minimum frequency D. operating frequency

B

375. An active integrator uses an op-amp, what is its feedback element? A. Resistor B. capacitor C. inductor D. RC network

B

387. What is true about the external frequency-compensation capacitor? A. the higher its value, the wider is its bandwidth B. the lower its value, the wider is its bandwidth C. the higher its value, the faster its slew rate D. A and C above

B

393. Op-amps whose internal transistor biasing can be controlled externally are categorize as A. general purpose op-amps B. programmable op-amps C. variable op-amps D. externally compensated op-amps

B

4. If a transistor is operated in such a way that output current flows for 160 degrees of the input signal, then it is ____________ operation. A. Class A B. Class C C. Class B D. Class AB

B

400. Which of the following is not an essential part of an oscillator? A. Source of energy that supply the losses in tank circuit. B. A resistor IC combination circuit. C. Resonant circuit consist of inductance and capacitance. D. Regenerative feedback circuit.

B

406. A self-excited oscillator in which the tank is divided into input and feedback portions by a capacitive voltage divider. A. Hartley capacitor B. Colpitts oscillator C. Relaxation oscillator D. Klystron oscillator

B

412. A multivibrator having two stable state A. monostable B. bistable C. astable D. unstable

B

413. Is also known as Eccles/Jordan circuit A. Monostable multivibrator B. bistable multivibrator C. astable multivibrator D. unstable multivibrator

B

414. Flip-flop is actually a _______ multivibrator. A. Monostable B. bistable C. astable D. unstable

B

428. It is a particularly important parameter that provides a direct link between current levels of the input and output circuits for a common-emitter configuration. A. α B. β C. A and B above D. none of these

B

444. A type of Oscillator that is very commonly used as local oscillator in superheterodyne radio receiver a. RC Phase Shift Oscillator b. Colpitt's Oscillator c. Clapp Oscillator d. Wien Bridge Oscillator

B

447. A type of flip-flop in which the data are entered and appear on the output on the same clock edge. a. Set Reset Flip flop b. Edge Triggered Flip flop c. JK Flip flop d. D Flip flop

B

449. Refers to the process of shrinking the size and power dissipation of electronic circuits. It also involves surface mount technology a. Gull wing b. Microminiaturization c. Floating Point d. Synchronous Deviation

B

452. It is a very high-gain differential amplifier with very high input impedance and very low output impedance. A. par-amp B. op-amp C. differential amp D. complementary amp

B

453. Ideally, op-amps have infinite input resistance and ________ output resistance. A. infinite B. zero C. variable D. a highly stabilized

B

453. _______________ is a secret key encryption technology that is used in client/server environments for secure authentication between computers a. Kepberos b. Kerberos c. Kesberos d. None of these

B

456. What do you call of the gain of an op-amp if operated in common mode input? A. differential gain B. common gain C. double-ended gain D. rejection gain

B

458. If op-amps are operated in differential mode, its gain is technically termed as A. common-mode differential gain B. differential gain C. open-loop gain D. closed-loop gain

B

460. An operational amplifier has a common-mode voltage gain of 10 and a differential-mode voltage gain of 20,000, calculate its common-mode rejection ratio (CMRR). A. 200 B. 2,000 C. 20,000 D. 200,000

B

462. What is the maximum output voltage swing of an op-amp? A. +V to -V (supply voltage) B. +VSAT to -VSAT C. +½V to -½V D. depends on the input signal

B

467. It is known through experiment that the input bias currents at the non-inverting (IB+) and inverting (IB-) inputs of a certain op-amp is 100 nA and 80 nA, respectively. Determine the op-amp's input offset current. A. -20 nA B. 20 nA C. 90 nA D. 180 nA

B

468. The reduction of op-amps gain due to increasing operating frequency. A. Cutoff B. roll-off C. diminishing factor D. reduction step

B

47. The voltage gain over mid- frequency range in an RC coupled amplifier A. Changes instantly with frequency B. Is constant C. Is independent of the coupling D. Is maximum

B

483. A self-excited oscillator in which the tank is divided into input and feedback portions by a capacitive voltage divider. A. Hartley capacitor B. Colpitts oscillator C. Relaxation oscillator D. Klystron oscillator

B

501. A transistor has how many PN junctions? A. 1 B. 2 C. 3 D. 4

B

504. The base of an NPN transistor is thin and A. heavily doped B. lightly doped C. metallic D. doped by a pentavalent material

B

506. When a transistor is fully switched ON, it is said to be A. shorted B. saturated C. open D. cut-off

B

518. There are h- parameters of a transistor. A. two B. four C. three D. none of the above

B

519. The h- parameter approach gives correct results for A. large signals only B. small signals only C. both small and large signals D. none of the above

B

527. A transistor amplifier has a voltage gain of 100. If the input voltage is 75 mV, the output voltage is: A. 1.33 v B. 7.5 v C. 13.3 v D. 15 v

B

736. In class A operation, the operating point is generally located ______ of the d.c. load line. A. at cut off point B. at the middle C. at saturation point D. none of the above

B

741. In class B power amplifiers, the output signal varies for of the cycle. A. 360° B. 180° C. between 180° and 360° D. less than 180°

B

746. The reflected impedance seen from one side of the transformer to the other side is . A. n1/n2 B. (n1/n2)2 C. (n1/n2)1/3 D. n1× n2

B

747. In a class A transformer-coupled power amplifier, winding resistance of the transformer determine(s) the dc load line for the circuit. A. the ac B. the dc C. both the ac and dc D. neither the ac nor dc

B

749. The amount of power dissipated by the transistor is the of that drawn from the dc supply (set by the bias point) and the amount delivered to the ac load. A. product B. difference C. average D. none of these

B

751. In a class A transformer-coupled amplifier, the the value of VCEmax and the the value of VCEmin, the efficiency to (from) the theoretical limit of 50%. A. larger, smaller, farther B. larger, smaller, closer C. smaller, larger, closer D. none of the above

B

755. The complementary Darlington-connected transistor for a class B amplifier provides output current and output resistance. A. higher, higher B. higher, lower C. lower, lower D. lower, higher

B

76. What class of operation is used either where the signal needs to be cut in half, such as in pulse detector or noise detectors or where push-pull operation of two stages is required? A. Class A B. Class B C. Class AB D. Class C

B

761. A heat sink provides thermal resistance between case and air. A. a high B. a low C. the same D. none of the above

B

767. amplifiers primarily provide sufficient power to an output load to drive a speaker from a few watts to tens of watts. A. small-signal B. power C. none of the above D. all of the above

B

772. What transformer turns ratio is required to match an 8-speaker load so that the effective load resistance seen at the primary is 12.8 k? A. 20:01 B. 40:01:00 C. 50:01:00 D. 60:01:00

B

773. Calculate the efficiency of a transformer-coupled class A amplifier for a supply of 15 V and an output of V(p) = 10 V. A. 25% B. 33.30% C. 50% D. 78.50%

B

774. The maximum efficiency of a transformer-coupled class A amplifier is _____. A. 25% B. 50% C. 78.5% D. 63.6%

B

781. Which of the following instruments displays the harmonics of a distorted signal? A. digital multimeter B. spectrum analyzer C. oscilloscope D. wave analyzer

B

789. The algebraic sum of in a network of conductors meeting at a point is zero. A. voltages B. currents C. resistances D. inductances

B

84. A dc voltage supply provides 60V when the output is unloaded. When connected to a load the output drops to 56V. Calculate the value of the voltage regulation. A. 8.1% B. 7.1% C. 5% D. 12%

B

88. In order to have more voltage gain from a transformer amplifier the transistor used should have A. Thin collector B. Thin base C. Wide emitter D. Thin emitter

B

94. What is the reason why RC coupling is not used to amplify extremely low frequencies? A. There is considerable power loss B. Electrical size of coupling capacitor becomes very large C. There is a hum in the output D. Electrical size of coupling capacitor becomes very small

B

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

C

546. A coupling capacitor is A. a dc short B. an ac open C. a dc open and an ac short D. a dc short and an ac open

C

30. The value of collector load resistance in a transistor amplifier is ___________ the output impedance of the transistor. A. Equal to B. More than C. Less than D. Not related

C

310. What type of amplifier commonly used at the output stage of op-amps? A. differential amplifier B. cascade-amplifier C. complementary amplifier D. darlington stage amplifier

C

311. The transistor configuration used at the output complementary stage of most op-amps A. cascode configuration B. common emitter C. common collector D. common base

C

32. The bandwidth of a single stage amplifier is ___________ that of multistage amplifier. A. Equal to B. Less than C. More than D. Independent

C

320. When one input of the op-amp is connected to ground and the other is to the signal source, its operation is called A. single-ended output B. double-ended output C. single-ended input D. double-ended input

C

325. Calculate the CMRR of an op-amp having a common-mode gain of 10 and a differential-mode gain of 100,000. A. 1000 dB B. 100 dB C. 80 dB D. 40 dB

C

326. The non-inverting and inverting inputs of an op-amp have an input voltage of 1.5 mV and 1.0 mV, respectively. If the op-amp has a common-mode voltage gain of 10 and a differential-mode gain of 10,000, what is its output voltage? A. 5.0 V B. 5.0125 mV C. 5.0125 V D. 25.0125 V

C

328. The µA741 op-amp has a CMRR of 90dB and a differential-mode voltage amplification of 200,000.What is the op-amp's common-mode voltage gain? A. 31,622.778 B. 632.40 C. 6.324 D. 0.158

C

331. The change in input offset current due to temperature change A. delta input offset current B. slew rate C. input offset current drift D. PSRR

C

360. A reduction of op-amp's voltage gain by a factor of two each time the frequency doubles. A. 2 dB/octave B. 2 dB/decade C. 6 dB/octave D. 6 dB/decade

C

457. When one input of the op-amp is connected to ground and the other is to the signal source, its operation is called A. single-ended output B. double-ended output C. single-ended input D. double-ended input

C

461. Calculate the CMRR of an op-amp having a common-mode gain of 10 and a differential-mode gain of 100,000. A. 1000 dB B. 100 dB C. 80 dB D. 40 dB

C

463. The µA741 op-amp has a CMRR of 90dB and a differential-mode voltage amplification of 200,000.What is the op-amp's common-mode voltage gain? A. 31,622.778 B. 632.40 C. 6.324 D. 0.158

C

466. The change in input offset current due to temperature change A. delta input offset current B. slew rate C. input offset current drift D. PSRR

C

629. "In any linear bilateral network, if a source of e.m.f. E in any branch produces a current I in any other branch, then same e.m.f. acting in the second branch would produce the same current / in the first branch". The above statement is associated with A. compensation theorem B. superposition theorem C. reciprocity theorem D. none of the above

C

63. The capacitors are considered ________________ in the dc equivalent circuit of a transistor amplifier. A. Short B. Partially short C. Open D. Partially open

C

631. A capacitor is generally a A. bilateral and active B. active, passive, C. linear and bilateral D. non-linear and

C

632. "In any network containing more than one sources of e.m.f. the current in any branch is the algebraic sum of a number of individual fictitious currents (the number being equal to the number of sources of e.m.f.), each of which is due to separate action of each source of e.m.f., taken in order, when the remaining sources of e.m.f. are replaced by conductors, the resistances of which are equal to the internal resistances of the respective sources". The above statement is associated with A. thevenin\s theorem B. norton\s theorem C. superposition theorem D. none of the above

C

634. Kirchhoff s law is not applicable to circuits with A. lumped parameters B. passive elements C. distributed parameters D. non-linear resistances

C

638. An ideal voltage source should have A. large value of e.m.f. B. small value of e.m.f. C. zero source resistance D. infinite source resistance

C

644. A non-linear network does not satisfy A. superposition condition B. homogeneity condition C. both homogeneity as well as superposition condition D. homogeneity, superposition and associative condition

C

646. A network which contains one or more than one source of e.m.f. is known as A. linear network B. non-linear network C. passive network D. active network

C

647. The superposition theorem is applicable to A. linear, non-linear and time variant responses B. linear and non- linear resistors only C. linear responses only D. none of the above

C

65. Power amplifiers handle _____________ signals. A. Very small B. Small C. Large D. Very large

C

654. Which of the following is a bilateral element? A. constant current source B. constant voltage source C. capacitance D. none of the above

C

657. A star circuit has element of resistance R/2. The equivalent delta elements will be A. r/6 B. 2r C. 3/2r D. 4r

C

786. A silicon power transistor is operated with a heat sink (θSA = 1.5°C/W). The transistor, rated at 150 W (25°C), has θJC = 0.5°C/W, and the mounting insulation has θCS = 0.6 °C/W. What is the maximum power that can be dissipated if the ambient temperature is 50°C and TJmax = 200 °C? A. 61.5 w B. 60.0 w C. 57.7 w D. 55.5 w

C

796. Node analysis can be applied for A. planar networks B. non-planar networks C. both a & b D. electric networks

C

82. The efficiency of class AB operation has a maximum of between _____________ percent. A. 90 to 100% B. 60 to 80% C. 50 to 78.5% D. 40.5 to 60%

C

83. Transformer coupling is generally employed when load resistance is A. Large B. Very large C. Small D. Zero

C

86. In transistor amplifiers, what transformer is used for impedance matching? A. Step up B. Power C. Step down D. Isolation

C

87. If an amplifier has a power gain of 100, then its dB gain is A. 10 B. 40 C. 20 D. 100

C

89. The final stage of an amplifier uses ____________ coupling. A. Direct B. RC C. Transformer D. Impedance

C

90. The largest theoretical voltage gain obtained with a common collector amplifier is A. 100 B. 10 C. Unity D. Infinite

C

91. Increasing the overall Beta is an advantage of A. Clap oscillator B. Crystal oscillator C. Darlington pair D. CE amplifier

C

95. Given three amplifiers with a gain of 10 and are connected in cascade. How much is the overall gain? A. 24 B. 10,000 C. 30 D. 20

C

96. A pair of filter common on high fidelity system which separate audio frequency band signals into two separate groups, where one is fed to the tweeter and the other to the woofer is called A. Equalizer B. Synthesizer C. Cross over network D. Hybrid

C

97. The frequency response of transformer coupling is A. Good B. Excellent C. Poor D. Very good

C

98. The simplest variable frequency sinusoidal oscillator is the A. Complicated Colpitts circuit B. Crystal circuit C. Armstrong circuit D. Phase shift circuit

C

99. Which of the following is provided by a CB transistor amplifier? A. Voltage gain B. Power gain C. Current gain D. Gain stability

C

367. Factor(s) or parameter(s) that determine(s) the op-amps maximum operating temperature A. PSRR B. slew rate C. unity-gain bandwidth product D. B and C above

D

1. Which of the following amplifier is considered linear? A. Class A B. Class B C. Class C D. Either A or B

D

112. An LC oscillator cannot be used to produce ____________ frequencies. A. High B. Very high C. Audio D. Very low

D

174. Parasitic oscillations are caused by A. Output negative feedback B. Push-pull operation C. Poor interstage coupling D. Transistor interelectrode capacitance

D

175. Which is a fixed-frequency oscillator A. Phase-shift oscillator B. Colpitt's oscillator C. Hartley oscillator D. Crystal oscillator

D

312. Why do most op-amps use a common collector at the output stage? A. to have a higher output power B. to have a better frequency response C. to have a low harmonic distortion D. to have a very low output resistance

D

316. Op-amps have two input terminals namely, the inverting (-) and non-inverting (+) inputs. What is the significance of its name? A. If a sine-wave is applied to the inverting (-) input, the output will be inverted or shifted by 180°, while if applied to the non-inverting (+) there will be no phase shift at the output. B. If pulses are applied to the inverting (-) input, the positive pulse becomes negative at the output and vice versa, while if applied at the non-inverting (+) there will be no reversal of the pulse at the output. C. In dc amplifier applications, increasing input at the inverting (-) terminal causes the output to decrease and vice versa, while at the non-inverting (+) input, the output magnitude goes with the input. D. all of these are correct

D

318. The operating mode of an op-amp, when both inputs are tied together or when the input signal is common to both inputs. A. differential mode B. rejection mode C. double-ended mode D. common mode

D

322. In op-amps, which gain is the highest? A. common-mode gain B. differential gain C. closed-loop gain D. open-loop gain

D

455. The operating mode of an op-amp, when both inputs are tied together or when the input signal is common to both inputs. A. differential mode B. rejection mode C. double-ended mode D. common mode

D

459. The ratio of the differential gain and common gain of an op-amp A. differential-common mode ratio B. common-mode ratio C. differential-mode rejection ratio D. common-mode rejection ratio

D

465. Ideal op-amp requires no input current, but real op-amp needs a very small input current called input bias current. At both inputs, the bias currents have a slight difference. What do you call this difference? A. differential input current B. differential bias C. input offset difference D. input offset current

D

470. Frequency at which the voltage gain of op-amp reduces to unity. A. unity-gain frequency B. cutoff frequency C. bandwidth point D. unity-gain bandwidth product

D

471. The low and high cutoff frequencies of an amplifier is also called A. corner frequencies B. 0.707 frequencies C. 3-dB frequencies D. all of these are correct

D

472. The maximum output voltage rate of change of an op-amp. A. rise time B. maximum voltage swing C. differential rate D. slew rate

D

473. Two comparators using op-amps, configured such that it can detect voltage levels within a certain range of values rather than simply comparing whether a voltage is above or below a certain reference. A. analog comparator B. regenerative comparator C. parallel comparator D. window comparator

D

778. Which of the following is (are) the disadvantage(s) of a class B complementary-symmetry circuit? A. it needs two separate voltage sources. B. there is crossover distortion in the output signal. C. it does not provide exact switching of one transistor off and the other on at the zero- voltage condition. D. all of the above

D

78. What class of operation has little use in general purpose amplifiers, but is used in high frequency oscillators? A. Class A B. Class AB C. Class B D. Class C

D

780. Calculate the harmonic distortion component for an output signal having fundamental amplitude of 3 V and a second harmonic amplitude of 0.25 V. A. 3.83% B. 38.3% C. 83.3% D. 8.33%

D

782. Which of the following instruments allows more precise measurement of the harmonic components of a distorted signal? A. digital multimeter B. spectrum analyzer C. oscilloscope D. wave analyzer

D

787. Which of the following transistors has been quite popular as the driver device for class D amplification? A. bjt B. fet C. ujt D. mosfet

D

793. Kirchhoff's voltage law is related to A. junction currents B. battery emfs C. ir drops D. both b & c

D

794. Superposition theorem can be applied only to circuits having A. resistive elements B. passive elements C. non-linear elements D. linear bilateral elements

D

795. The concept on which superposition theorem is based on A. reciprocity B. duality C. non-linearity D. linearity

D

798. The superposition theorem is applicable to A. voltage only B. current only C. current and voltage D. current, voltage and power

D

8. What piece of equipment in an oscilloscope is used to indicate pulse condition in a digital logic circuit? A. Probe B. Test prods C. Connector D. Logic probe

D

290. A multistage transistor amplifier arranged in a conventional series manner, the output of one stage is forward-coupled to the next stage. A. cascaded amplifier B. cascoded amplifier C. darlington configuration D. feed-back pair configuration

A

293. Famous transistor amplifier configuration designed to eliminate the so called Miller effect. A. cascode amplifier B. darlington amplifier C. differential amplifier D. complementary-symmetry

A

298. An amplifier basically constructed from two transistors and whose output is proportional to the difference between the voltages applied to its two inputs. A. differential amplifier B. cascode amplifier C. complementary amplifier D. quasi-complementary amplifier

A

299. An amplifier having high direct-current stability and high immunity to oscillation, this is initially used to perform analog-computer functions such as summing and integrating. A. operational amplifier (op-amp) B. parametric amplifier (par-amp) C. instrumentation amplifier D. DC-amplifier

A

3. A two-transistor class B power amplifier is commonly called A. Push-pull amplifier B. Dual amplifier C. Symmetrical amplifier D. Differential amplifier

A

304. The circuit at the input stage of operational amplifiers A. differential amplifier B. cascaded amplifier C. current mirror D. complementary amplifier

A

352. In large signal dc-amplifiers using op-amp, which parameter has the least effect on its performance? A. drift B. slew rate C. input offset voltage D. input offset current

A

355. What do we mean by internally compensated op-amps? A. Op-amps with internal frequency compensation capacitor to prevent oscillation. B. Op-amps with an internal compensating resistor to make the output offset voltage zero. C. Op-amps with internal coupling capacitor to block dc-voltages and allows ac voltages to pass. D. Op-amps with internal active components to make its gain constant at the entire operating frequency.

A

359. What do we mean by a 20 dB/decade roll-off? A. a gain reduction by a factor of 10 per decade B. a gain reduction by a factor of 20 per decade C. a gain reduction by a factor of 10 per 10 Hz increased in frequency D. a gain reduction by a factor of 20 per 10 Hz increased in frequency

A

36. Which configuration has the lowest current gain? A. Common-base B. Common-collector C. Common-emitter D. Emitter follower

A

363. Calculate the cutoff frequency (fc) of an op-amp having a unity-gain bandwidth product B1 = 1 MHz and a open-loop voltage gain AOL = 100,000. A. 10 Hz B. 20 Hz C. 100 Hz D. 200 Hz

A

368. What is the maximum signal frequency that can be used in an op-amp having a specified slew rate of 0.5 V/µsec? The maximum output voltage desired is 5 V. A. 16 kHz B. 32 kHz C. 100 kHz D. 1 MHz

A

464. The current needed at the input of an op-amp to operate it normally A. input bias current B. input offset current C. input threshold current D. input holding current

A

474. The feedback element of a differentiator constructed from op-amp is A. a resistor B. an inductor C. a capacitor D. an RC network

A

476. The voltage gain of an op-amp voltage follower. A. unity B. Rf/Ri C. 1 + Rf/Ri D. depends on the type of op-amp

A

477. Calculate the closed-loop voltage gain of an inverting amplifier having a feedback and an input resistance of 100 kΩ and 10 kΩ, respectively. A. 10 B. 11 C. 100 D. 110

A

484. A self-excited oscillator in which the tank is divided into input and feedback portions by an inductive voltage divider or a tapped coil. A. Hartley oscillator B. Copitts oscillator C. Relaxation oscillator D. Klystron oscillator

A

485. A circuit usually containing two transistors or tubes in an RC-coupled amplifier, the two active devices switch each other alternately on and off. A. Multivibrator B. Signal generator C. Oscillator D. Thyristor

A

486. A multivibrator that generates one output pulse for each input trigger pulse. A. monostable B. astable C. bistable D. tristate

A

493. Filter that is characterized by a relatively flat passband and slow roll-off rate a. Butterworth b. Elliptic c. Chebyshev d. Notch

A

497. What happens to the input resistance of an amplifier employing voltage-series feedback? a. It is increased b. It remains the same c. It is decreased d. Equals infinity

A

499. If the gain of an amplifier without feedback is 10 and with negative feedback is 8, then the feedback fraction is a. 0.025 b. 0.9 c. 0.8 d. 0.225

A

5. Which coupling has the best frequency response? A. Direct B. RC C. Transformer D. Transistor

A

50. To obtain the frequency response curve of an amplifier ___________ is kept constant. A. Generator output level B. Amplifier output C. Generator frequency D. Amplifier frequency

A

502. In an NPN transistor, the majority carriers in the emitter are A. free electrons B. holes C. neither D. both

A

505. The emitter of a transistor is generally doped the heaviest because it A. has to dissipate maximum power B. has to supply the charge carriers C. is the first region of the transistor D. must possess low resistance

A

511. What are the two types of bipolar junction transistors? A. NPN and PNP B. PNN and NNP C. PPN and NNP D. PTS and STP

A

517. Hybrid means A. mixed B. single C. biunique D. none of the above

A

520. If the operating point changes, the h-parameters of transistor A. also change B. do not change C. may or may not change D. none of above

A

538. A JFET data sheet specifies VGS(off) = -6 V and IDSS = 8 mA. Find the value of ID when VGS = -3 V. A. 2 ma B. 4 ma C. 8 ma D. none of the above

A

121. Transformer coupling introduces what type of distortion? A. Amplitude B. Frequency C. Phase D. Intermodulation

B

106. What is the typical value of the emitter bypass capacitor CE in a multistage amplifier? A. About 0.1 µF B. About 50 µF C. About 100 pF D. About 0.01 µF

B

110. Transformer coupling provides high gain because A. Transformer is very efficient B. Impedance matching can be achieved C. Transformer steps up the voltage D. Transformer steps up the current

B

115. An oscillator oscillates due to A. Negative feedback B. Positive feedback C. Both positive and negative feedback D. Neither positive nor negative feedback

B

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

B

207. The current gain of an emitter follower is A. Equal to 1 B. Greater than 1 C. Less than 1 D. Zero

B

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

B

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

B

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

B

22. An AF transformer is shielded to A. Keep the amplifier cool B. Prevent the induction due to stray magnetic fields C. Protect from rusting D. Prevent electric shock

B

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

B

227. In a common emitter amplifier, the capacitor from emitter to ground is called the A. Coupling capacitor B. Bypass capacitor C. Decoupling capacitor D. Tuning capacitor

B

228. A class A power amplifier uses ________ transistor(s). A. Two B. One C. Three D. Four

B

23. Amplitude distortion is otherwise known as ___________ distortion. A. Intermodulation B. Harmonic C. Phase D. Resonant

B

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

B

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

B

236. The push-pull circuit must use ___________ operation. A. Class A B. Class B C. Class C D. Class AB

B

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

B

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

B

262. A class A amplifier has an efficiency of only 25%, but this can be increased if the output is coupled with a transformer. Up to how much is its efficiency will reach due to coupling? A. 36.5% B. 50% C. 68.5% D. 78.5%

B

267. Among the given amplifiers below, which is the most efficient? A. class A (series-fed) B. class A (transformer-coupled) C. class A (directly-coupled) D. class A (capacitor-coupled)

B

27. If gain without feedback and feedback factor are A and β respectively, then gain with negative feedback is given by A. A/ 1-A β B. A/ 1+ A β C. 1+A β / A D. (1+A β) A

B

271. The Q-point for class A amplifier is at the active region, while for class B it is at cutoff region, how about for class AB? A. it is slightly below saturation B. it is slightly above cutoff C. it is slightly above saturation D. it is at the saturation region

B

278. A push-pull amplifier that uses npn and pnp transistors to amplify the positive and negative cycles respectively. A. transformer-coupled push -pull amplifier B. complementary-symmetry amplifier C. quasi-complementary push-pull amplifier D. transformer-coupled class A amplifier

B

282. A type of distortion wherein the output signal does not have the desired linear relation to the input. A. linear distortion B. nonlinear distortion C. cross-over distortion D. all of the above

B

283. Distortion that is due to the inability of an amplifier to amplify equally well all the frequencies present at the input signal. A. nonlinear distortion B. amplitude distortion C. harmonic distortion D. cross-over distortion

B

285. Calculate the 2nd harmonic distortion for an output signal having a fundamental amplitude of 3V and a 2nd harmonic amplitude of 0.3 V. A. 1.0% B. 10% C. 23.33% D. 43.33%

B

286. An amplifier has the following percent harmonic distortions; D2 = 10%, D3 = 5% and D4 = 1%. What is the amplifier % THD? A. 5.33% B. 11.22% C. 16.0% D. 22.11%

B

292. A two-stage transistor amplifier in which the output collector of the first stage provides input to the emitter of the second stage. The final output is then taken from the collector of the second stage. A. cascade configuration B. cascode configuration C. quasi-complementary D. complementary amplifier

B

301. It is a very high-gain differential amplifier with very high input impedance and very low output impedance. A. par-amp B. op-amp C. differential amp D. complementary amp

B

303. An operational amplifier must have at least how many usable terminals? A. 3 terminals B. 5 terminals C. 8 terminals D. 14 terminals

B

308. Ideally, op-amps have infinite input resistance and ________ output resistance. A. infinite B. zero C. variable D. a highly stabilized

B

31. What is the purpose of RC or transformer coupling? A. To block ac B. To separate bias of one stage from another C. To increase thermal stability D. To block dc

B

319. What do you call of the gain of an op-amp if operated in common mode input? A. differential gain B. common gain C. double-ended gain D. rejection gain

B

321. If op-amps are operated in differential mode, its gain is technically termed as A. common-mode differential gain B. differential gain C. open-loop gain D. closed-loop gain

B

332. The reason why a slight difference between the input bias current occurs in op-amps is due to the unsymmetrical circuit component parameters. This unsymmetrical condition also produces a difference in input voltage called what? A. drift voltage B. differential voltage C. input offset voltage D. input threshold voltage

C

335. Ideally, the output voltage of an op-amp is zero when there is no input signal, however, in practical circuits, a small output voltage appears, this voltage is known as A. minimum output voltage B. pinch-off voltage C. output offset voltage D. saturation voltage

C

339. The output offset voltage of an op-amp is due to the input offset current and voltage. If 1 mV is due to the input offset current and 22 mV due to the input offset voltage, what is the total output offset voltage of the op-amp? A. 11.5 mV B. 22 mV C. 23 mV D. 45 mV

C

347. An op-amp is wired as an inverting amplifier with an input and feedback resistances of 1 kΩ and 100 kΩ, respectively. When the input signal is set to zero, the output was found to have an offset voltage of 101 mV. Calculate the input offset voltage. A. 0.01 mV B. 0.1 mV C. 1.0 mV D. 10.0 mV

C

351. Op-amp parameter(s) that is important in large signal dc-amplification. A. input offset voltage B. input offset current C. slew rate D. all of the above

C

354. If an op-amp is used to amplify small ac-signals, what parameter you should greatly consider to ensure better performance? A. input bias current B. drift C. frequency response D. slew rate

C

357. What will happen to the voltage gain of op-amp when its operating frequency is increased? A. also increases B. increases exponentially C. will decrease D. decreases exponentially

C

364. An op-amp has a specified transient response rise time of 0.3 µs, calculate its unity-gain bandwidth. A. 0.857 MHz B. 1.0 MHz C. 1.167 MHz D. 2.334 MHz

C

369. What must be the slew rate of an op-amp to be used in order to provide an undistorted output voltage of .10 V ac a frequency of 100,000 rad/sec? A. 0.1 V/µsec B. 0.5 V/µsec C. 1.0 V/µsec D. 6.28 V/µsec

C

383. In most ac-amplifiers using op-amps, the feedback resistor is shunted with a very small capacitance, what is its purpose? A. to prevent oscillation B. to improve stability C. to minimize high frequency noise D. to compensate for high frequency loss

C

397. For high density ICs involving many op-amps, what packaging is suitable? A. metal can B. 14-pin DIL C. SMT D. flat-pack

C

399. Which condition must exist for a circuit to oscillate? A. It must have a negative feedback sufficient to cancel the input B. It must have a gain of less than 1 C. It must have a positive feedback sufficient to overcome losses D. It must be neutralized

C

40. AC load line has a/an _____________ slope compared to that of dc load line. A. Zero B. Smaller C. Bigger D. Infinite

C

403. What determines the resonant frequency of a crystal? A. external components B. the temperature of the crystal C. the size and thickness of the crystal material D. the hermitic seal

C

404. Type of oscillator whose frequency is dependent on the charge and discharge of RC networks. A. Hartley oscillator B. Colpitts oscillator C. Relaxation oscillator D. Klystron oscillator

C

415. Considered as a free-running multivibrator A. monostable B. bistable C. astable D. unstable

C

417. Which class of amplifiers that is intended for pulse operation? A. class B B. class C C. class D D. class S

C

420. If three amplifiers with a gain of 8 each are in cascade, how much is the overall gain? A. 72 B. 24 C. 512 D. 8

C

438. A BJT is a current-controlled current-source device while JFET is a _________ device. A. current-controlled voltage-source B. voltage-controlled voltage-source C. voltage-controlled current-source D. voltage-controlled transconductance-source

C

442. What is formed on the screen of cathode ray oscilloscope when two sine wave voltages are simultaneously applied to the two sets of deflection plates? a. Lizzajous pattern b. Lisajous pattern c. Lissajous pattern d. Lizajous pattern

C

450. A non-volatile read/write random access semiconductor memory in which data are stored as charge on the floating gate of a certain type of FET a. PROM b. Hard Disk c. Flash Memory d. RAM

C

451. It is a channel model in which the input and output alphabets x and y are discrete sets and the channel is memoryless a. The Discrete Memory Channel b. The Discrete channel c.The Discrete Memoryless Chanel d. None of these

C

454. What is the circuit which has a purpose to quiet a receiver in the absence of a received signal? a. Squilch circuit b. Squealch circuit c. Squelch circuit d. Squeltch circuit

C

46. A tuned amplifier uses what load? A. Resistive B. Capacitive C. LC tank D. Inductive

C

469. A reduction of op-amp's voltage gain by a factor of two each time the frequency doubles. A. 2 dB/octave B. 2 dB/decade C. 6 dB/octave D. 6 dB/decade

C

479. Which condition must exist for a circuit to oscillate? A. It must have a negative feedback sufficient to cancel the input B. It must have a gain of less than 1 C. It must have a positive feedback sufficient to overcome losses D. It must be neutralized

C

48. The input impedance of an amplifier _____________ when negative voltage feedback is applied. A. Decreases B. Becomes zero C. Increases D. Is unchanged

C

480. Circuits that produces alternating or pulsating current or voltage. A. Damper B. Generator C. oscillator D. mixer

C

481. What do you call the oscillator circuit that uses a tapped coli in the tuned circuit? A. Pierce B. Colpitts C. Hartley D. Ultraudion

C

131. Which of the items below is not a description of the two-stage amplifier? A. The input resistance is equal to the input resistance of the first stage unless feedback is applied B. Its output resistance is equal to the output resistance of the final stage unless feedback is applied C. Its noise level is equal to the accumulated noise of the two stages, either by multiplying the noise voltage amplitudes together or by adding the noise decibel levels together D. The output resistance is equal to the output resistance of the first stage unless feedback is applied.

D

136. What is the typical Q of a crystal? A. 100 B. 50 C. 1000 D. More than 10,000

D

145. The bandwidth of an amplifier _____________ when negative feedback is applied. A. Decreases B. Remains unchanged C. Becomes infinite D. Increases

D

147. Emitter follower employs ____________ negative feedback. A. 50% B. 25% C. 75% D. 100%

D

190. An amplifier with efficiency of 85% is likely to be A. Class A B. Class B C. Class AB D. Class C

D

195. What is the maximum collector efficiency of class B? A. 50% B. 90% C. 60.5% D. 78.5%

D

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

D

210. An open fuse circuit has a resistance equal to A. Zero B. Unity C. At least 100Ω at standard D. Infinity

D

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 Vrms A. 5% B. 10% C. 50% D. 6%

D

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

D

230. What is the maximum collector efficiency of a transformer coupled class A power amplifier? A. 30% B. 80% C. 45% D. 50%

D

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

D

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

D

252. Class A amplifier can be built from what transistor configuration? A. common base B. common emitter C. common collector D. all of the above

D

255. A class of amplifiers wherein the output signal swings more than 180° but less than 360°. A. class A B. class B C. class C D. class AB

D

259. How do you classify an amplifier used to amplify either amplitude modulated (AM) or frequency modulated (FM) signals? A. class C B. class BC C. class D D. class S

D

260. Which class of amplifiers that has the highest efficiency? A. class A B. class B C. class C D. class D

D

265. For pulse-amplification, class D amplifier is mostly used. How efficient is a class D amplifier? A. about 25% efficient B. less efficient than class B C. more efficient than class A but less efficient than class B D. its efficiency reaches over 90%

D

269. In most transistor class A amplifiers, the quiescent point is set at A. near saturation B. near cutoff C. below cutoff D. at the center

D

270. For a class B amplifier, the operating point or Q-point is set at A. the top of the load line B. saturation C. the center D. cutoff

D

272. Where does the Q-point of a class C amplifier positioned? A. at saturation region B. at active region C. at cutoff region D. below cutoff region

D

273. The Q-point of a class D amplifier can be set or positioned at what region in the load line? A. below saturation B. above cutoff C. at cutoff D. any of the above

D

274. Which of the amplifiers given below that is considered as non-linear? A. class A B. class B C. class AB D. class C

D

275. Which amplifiers can be used for linear amplification? A. class A B. class B C. class C D. class A or B

D

276. What do you call an amplifier that is biased to class C but modulates over the same portion of the curve as if it were biased to class B? A. class S B. class D C. class AB D. class BC

D

280. Amplifiers conversion efficiency are calculated using what formula? A. ac-power/dc-power B. ac-power/dissipated power C. dc-power/ac-power D. A or B are correct

D

284. A nonlinear distortion in which the output consists of undesired harmonic frequencies of the input signal. A. amplitude distortion B. frequency distortion C. cross-over distortion D. harmonic distortion

D

294. What are the transistor configurations used in a cascade amplifier? A. common-base and common-emitter B. common-base and common-collector C. common-collector and common-emitter D. common-emitter and common-base

D

297. Transistor arrangement that operates like a darlington but uses a combination of pnp and npn transistors instead of both npn. A. differential B. common C. cascode D. feedback pair

D

300. One of the most versatile and widely used electronic device in linear applications. A. SCR B. FET C. UJT D. op-amp

D

302. What are the possible applications of operational amplifiers (op-amps)? A. ac and dc-amplifiers B. oscillators and signal conditioning C. voltage-level detectors and comparators D. all of the above

D

306. In op-amps functional block diagram, what follows the differential amplifier? A. cascode-amplifier B. complementary amplifier C. level shifter D. high gain amplifier

D

309. How does the input of an op-amp made high? A. by using super beta transistor at the input differential stage B. by using FETs at the input differential stage C. by connecting a very high resistance in series with the input differential stage D. A and B above

D

323. The ratio of the differential gain and common gain of an op-amp A. differential-common mode ratio B. common-mode ratio C. differential-mode rejection ratio D. common-mode rejection ratio

D

330. Ideal op-amp requires no input current, but real op-amp needs a very small input current called input bias current. At both inputs, the bias currents have a slight difference. What do you call this difference? A. differential input current B. differential bias C. input offset difference D. input offset current

D

336. The output offset voltage of an op-amp is (are) due to A. input offset current B. input offset voltage C. voltage and current drift D. A and B above

D

338. An op-amp inverting amplifier uses a feedback resistor of 100 kΩ and input resistor of 10 kΩ. If the op-amps input offset voltage is 2.0 mV, approximate the amplifier output offset voltage due to this input offset voltage. A. 10 mV B. 11 mV C. 20 mV D. 22 mV

D

341. What is a bias-current compensating resistor in op-amp circuits? A. A resistor used to reduce the undesired output offset voltage due to the input offset current. B. A resistor connected between the non-inverting terminal and ground. C. A resistor used to balance both input bias currents and therefore eliminates the input offset current. D. all of these

D

342. The approximate value of the bias-current compensating resistor in op-amp circuits is A. equal to the feedback resistor B. equal to the input resistor C. equal to the series combination of the input and feedback resistors D. equal to the parallel combination of the input and feedback resistors

D

345. What is the effect of the input offset voltage to the output voltage if the op-amp has no feedback element? A. causes the output to be always at cutoff B. causes the output to saturate towards positive C. causes the output to saturate towards negative D. causes the output to saturate either towards positive or negative

D

348. What is the most effective way of minimizing the output offset voltage of an op-amp? A. by reducing the value of the feedback resistor B. by increasing the value of the input resistor C. by a capacitor-compensation technique D. by properly using and adjusting the offset-null terminals

D

349. What cause(s) the well-adjusted output offset voltage of op-amps to change? A. change in operating temperature B. component aging C. variations in supply voltage D. all of the above

D

350. Which op-amp parameter(s) that normally affects its small signal dc-amplification performance? A. input bias current B. input offset voltage C. input offset current D. all of the above

D

353. For ac-amplifiers using op-amps what parameters can affect its performance. A. input offset current and voltage B. input bias current and voltage C. drift and slew rate D. slew rate and frequency response

D

361. Frequency at which the voltage gain of op-amp reduces to unity. A. unity-gain frequency B. cutoff frequency C. bandwidth point D. unity-gain bandwidth product

D

362. The low and high cutoff frequencies of an amplifier is also called A. corner frequencies B. 0.707 frequencies C. 3-dB frequencies D. all of these are correct

D

365. Rise time is defined as the time required for the output voltage to rise from _______ to ________ of its final value. A. 0% - 100% B. 1% - 99% C. 5% - 95% D. 10% - 90%

D

366. The maximum output voltage rate of change of an op-amp. A. rise time B. maximum voltage swing C. differential rate D. slew rate

D

382. Which of the following of the resistor combinations that provides lesser noise in op-amp circuits? A. Make both the feedback and input resistances as large as possible B. Make the feedback as large as possible, while the input as low as possible. C. Make the feedback as low as possible, while the input as large as possible. D. Make the feedback and input resistances as small as possible.

D

384. Approximate the noise gain of an inverting adder using op-amps if it has five inputs. A. unity (1) B. two (2) C. four (4) D. six (6)

D

385. Op-amps with internal frequency compensation are very stable with respect to signal frequencies. However, the trade-off for frequency stability is (are) A. limited small-signal bandwidth B. slow slew rate C. limited open-loop frequency response D. all of these

D

386. What do we mean by externally compensated op-amps? A. op-amps with frequency-compensation terminals B. op-amps with provision to externally compensate for frequency stability C. op-amps whose gain is externally compensated D. A and B above

D

388. Typical value of the external frequency-compensating capacitor of op-amps. A. 3 - 30 nF B. 30 - 300 nF C. 0.3 - 3.0 µF D. 3.0 - 30 µF

D

389. What do we mean by a general-purpose op-amps? A. op-amps with limited unity-gain bandwidth up to approximately 1 MHz B. op-amps with slew rate about 0.5 V/µsec C. op-amps that has unlimited application D. A and B above

D

390. Op-amps designed to operate at high slew rate, about 2000 V/µsec and at high frequencies, more than 50 MHz. A. general purpose op-amps B. high power op-amps C. high-stability op-amps D. high-frequency, high-slew rate op-amps

D

391. Generally, where does hybrid op-amps found its application? A. for high-output voltage B. for high-output current C. for high-frequency D. A and B above

D

394. What op-amp parameter(s) that can be governed by the bias control in a programmable op-amp? A. open-loop gain and slew rate B. unity-gain bandwidth C. input bias current D. all of the above

D

416. A class of amplifiers wherein the output signal swings more than 180° but less than 360°. A. class A B. class B C. class C D. class AB

D

628. "Maximum power output is obtained from a network when the load resistance is equal to the output resistance of the network as seen from the terminals of the load". The above statement is associated with A. mill man's theorem B. thevenin\s theorem C. superposition theorem D. maximum power transfer theorem

D

715. The principal advantage(s) of MOSFETs over BJTs is (are) A. their biasing networks are simpler. B. their drive requirements are simpler. C. they can be connected in parallel for added drive capability. D. all of the above

D

739. The main feature(s) of a large-signal amplifier is (are) the A. circuit's power efficiency B. maximum amount of power that the circuit is capable of handling C. impedance matching to the output D. all of the above

D

742. amplifiers have the highest overall efficiency. A. class a B. class b or ab C. class c D. class d

D

757. In Fourier technique, any periodic distorted waveform can be represented by the fundamental and all harmonic components. A. multiplying B. subtracting C. dividing D. adding

D

768. The main features of a large-signal amplifier is the circuit's ______ . A. power efficiency B. maximum power limitations C. impedance matching to the output device D. all of the above

D


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