Electronics Engineering Review Materials: Section 1 Module 7

(Last Updated On: December 8, 2017)

This is the Section 1 Module 7 of the compiled Electronics Review Materials taken from different sources including but not limited to Electronics books, past Board Exams Questions, Journals and the Internet. This particular reviewer in Electronics Engineering has random Questions and Answers in random topics. Make sure to familiarize each questions to increase the chance of passing the ECE Board Exam.

Electronics Engineering Reviewers: Section 1 Module 7

1. The Sallen Key filter

– Second order filter

2. The drain current in the current circuit when constant current area increases.

– The gate to source bias voltage decreases

3. Semiconductor is reversed bias with large enough voltage will conduct, this is because of

– avalanche effect

4. T-MOSFET is a kind of

– EMOSFET

5. Difference between SCR and SCS

– Has two gate terminals

6. Which of the following characteristics does not necessarily apply to op-amp?

– Low power

7. A phase shift through op-amp is because of

– Internal RC circuit

8. A FET does not has

– Forward biased PN junction

9. An operational amplifier must have at least how many usable terminals?

– 5

10. Generating a voltage in a generator will likely to happen only when

– There is relative 1 motion between conducting wire and magnetic line of force.

11. Two essentially parts of rotating generator.

– Electro/permanent magnet and armature winding

12. Generally a DC generator

– The armature winding is rotated with respect to a magnetic force produced by electromagnets or permanent magnets.

13. A junction of two conductors that exhibits electrical characteristics during changing temperature condition.

– Thermoelectric conduction

14. How does electric field in JFET established?

– By the presence of charge at gate terminal during reversed bias.

15. Relaxation oscillators are based on

– By charging and discharging of capacitor

16. Load regulation

– Changing load and output voltage remains constant

17. Transient suppression minimized the chance of

– Diode failure

18. If two waves, have the same frequency and the same phase, the composite wave is equal to:

– Magnitude of the sum of two original waves

19. The current consists mainly of holes when a JFET

– Has P – type channel

20. A basic isolation amplifiers has 3 electrically isolated parts

– Input, output, power

21. The most important transistor characteristic curve

– Output characteristic curve

22. In a voltage divider bias npn transistor, what happen when the resistor on the higher place opens?

– The transistor goes to cut-off

23. Which statement is true about alternator?

– High speed alternator is smaller than the lower speed

24. What is the used of noise generator?

– Evaluating the noise characteristics of an amplifier.

25.

– make the feedback and input resistances as smaller as possible.

26. What is the purpose of current limiting in regulators?

– To protect the regulator from excessive current.

27. In power distribution, the most commonly used insulator

– Porcelain

28. In Zener diode, when the zener voltage is 3.6 V

– Zener breakdown

29. The realistic open loop gain

– 100, 000

30. When frequency of the open loop gain is equal to 1.

– Unity gain frequency

31. Phase shift of the ac sine wave by 90 degrees is the same as the

– Rotating from left/right by ¼ cycle

32. In RL circuits, the ratio of XL/R decreases, phase angle

– Decreases

33. Common-base configuration application

– Radio frequency power amplifier

34. Found at the output of the op-amp

– complementary amplifier

35. SCR differs from four layer diode

– It has gate terminal

36. Difference between SCR and SCS

– Has two gate terminals

37. Air works well as dielectric because

– It has low loss

38. The use of I layer in PIN diode

– Minimize the diode capacitance

39. TMOSFET is a kind of

– EMOSFET

40. Which FET has a wide and short effective channel

– VMOSFET

41. A circuit used for voltage equalization during on-off switching action of SCRs in series

– Snubber circuit

42. The external resistor of instrumentation amplifier is used to

– sustain voltage gain

43. The low pass is cascaded to he high pass filter, the critical frequency of the low pass filter is

– Greater than the critical frequency of the low pass filter

44. The most popular op-amp packages are the metal can, 8-pin DIP, the SMT. Which of the following corresponds to TO-99?

– Metal can

45. The magnitude of the op-amps input offset voltage before it can be classified as a low input offset voltage op-amp.

– 0.2 mV

46. High voltage is used in long distance power transmission because

– The I2R losses are lower

47. The forward breakover voltage of a silicon diode is

– About 0.6V

48. Which bipolar amplifier type has same distortion in the signal wave, with collector current during the most, but not at all of the cycle

– Class AB2

49. The frequency at which the crystal oscillator functions is determined mainly by

– The thickness of the crystal

50. In an AND gate the output is high

– Only when all inputs are high

51. In an Exclusive OR gate the output is high

– Only when the inputs have opposite logic states

52. What type of generator consists of a single coil rotated in a magnetic field?

– Elementary generator

53. Which does not affect the inductance of the coil

– Diameter of the wire

54. When two or more generators are applying a common load

– Parallel generators

55. An early version of the field effect transistor in which limited control of current carriers near the surface of a semiconductor bar or film was obtained by an external field applied transversely

– Fieldistor

56. A push-pull amplifier that uses NPN and PNP transistors to amplify the positive and negative cycles respectively

– Complementary symmetry amplifier

57. The frequency at which open loop gain is equal to one

– Unity gain frequency

58. Which of the ff. is does not have an output terminal of a 555 timer?

– Clock

59. In an OTA transconductance varies with

– Bias current

60. The efficiency of a class AB amplifier is

– Slightly less than class B

61. When choosing dc motor

– Speed-torque

62. It is a modified version of wheatstone-bridge, it is used to measure low resistances

– Kelvin Double bridge

63. Simplified wheatstone bridge, the ratio arm is replaced by constant time of uniform cross section exactly 100 cm long

– Slide wire bridge

64. Used to measure the impedance of both inductance and capacitance at higher frequencies

– Radio frequency bridge

65. This bridge is used to measure capacitance

– Schering bridge

66. The peak current of a class A amplifier

– Quiescent current

67. In Rectifier diode, current is approximately by how much of an ac cycle

– 180o

68. The armature winding is connected to its own positive and negative terminals

– Self excitation

69. Configuration with highest amplification

– Common-emitter

70. Substance that generates voltage when exposed to light

– Photovoltaic material

71. 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 taken from the collector of the second or last stage.

– Cascade configuration

72. The output on the first stage amplifier is connected on the base of the second stage amplifier. The configuration is

– Cascade configuration

73. The power amplifier is connected using

– Transformer coupling

74. It shows or displays and print the waveform of the transmitter and harmonics

– Spectrum analyzer

75. It shows the wave for a long period of time

– Storage oscilloscope

76. When the input of the op-amp is noisy

– Change back and forth erratically between two states

77. A basic instrumentation amplifier is formed bt

– 3 op-amps and 7 resistors

78. When triangular wave is the input of the integrator, what is the output?

– Square wave

79. When severe arcing is noticeable in motor

– During starting

80. The power dissipation of class C amplifier

– Very low

81. Cross-over distortion is mainly problem of

– Class B

82. Acoustic feedback in public address system

– It serves no purpose

83. In op-amp the common mode voltage gain is 10 and the differential mode voltage gain is 20000, calculate the CMRR

– 2000

84. In wein bridge oscillator positive feedback circuit has

– Lead lag circuit

85. In all the resistor combination which provides lesser noise in the op-amp

– Make both feedback and input resistance as small as possible

86. When two inputs of the multiplier is connected together it operates as

– Squaring circuit

87. Provides offset nulling

– Zero output at error voltage

88. Damping factor at the filter is set by

– Negative feedback circuit

89. In resonance, the resistance in common-base decrease will

– Not affect the common-collector

90. Case of load regulator

– When load changes the output voltage stays constant

91. UJT never has

– Forward biased PN junction

92. In voltage divider bias NPN transistor, the upper voltage divider resistor when open is

– The transistor goes to cutoff

93. Most wires of the isolation amplifiers are connected at

– Transformer

94. The ac generator is

– By dc-generator supply to the dc-excitation to the rotating field

95. The operation of logarithmic amplifiers is based on

– Logarithmically change of a PN junction

96. What term applies to the use of two or more generators to supply a common load?

– Parallel operation/generators

97. Change in Input offset current due to temperature change

– Input offset current drift

98. The UJT has

– A bilateral conduction

99. A DC motor

– Is composed of armature winding and permanent magnet

100. Is a measure of an op-amp’s ability to reject common-mode inputs.

– CMRR

Section 1 Modules: Reviewers in Electronic Engineering