This is the Section 1 Module 4 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 4
1. The basic requirement of a dc armature winding is that it must be.
- A closed one
2. A wave winding must go at least ____ around the armature before it closes back where it started
- Twice
3. The primary reason for making the coil span of a dc armature winding equal to a pole pitch is to.
- Distribute the winding uniformly under different poles
4. The sole purpose of a commutator in a dc generator is to.
- Convert the induced ac to dc
5. A thermocouple.
- Gets warm when current flows through it.
6. In a linear meter, half scale deflection occurs when there is ____ percent of the rated current through its coil.
- 50
7. Digital instruments are those which.
- Have circuitry of digital design
8. The basic meter movement can be converted into an ohmmeter by connecting a ___ with it.
- Battery and a variable resistance in series
9. The D’ arsonval meter movement can be converted into a audio frequency ac ammeter by adding a _____ to it
- rectifier
10. In small dc machines, armature slots are sometimes not made axial but are skewed. Though skewing makes winding a little more difficult, yet results in,
- Quilter operations and slightly decrease in losses.
11. For a Q point near the center of the dc load line, clipping is more likely to occur on the,
- Negative peak of output voltage
12. The dc armature winding in which coil sides are a pole pitch apart is called ____ winding
- Full- pitch
13. For making coil span equal to a pole pitch in the armature winding of a dc generator, the back pitch of the winding must equal the number of
- Commutator bars per pole
14. 339 IC function as.
- Comparator
15. How many comparators does a 339 IC contains?
- 4
16. AC compound generator usually has lower resistance.
- Series field winding
17. BIMOSFET circuit.
- Bipolar and mosfet circuit
18. Advantage of MOSFET over FET
- MOSFET can handle wide range of gate voltage.
19. Class A maximum efficiency
- 50%
20. SCS terminals
- 4
21. MOSFET terminals
- 3 or 4
22. Limited to negative resistance region
- Phototransistor
23. Graph of AC emitter current and ac base-emitter voltage.
- Diode emitter
24. PUT programmable unijunction transistor terminals
- 3
25. Amplifiers generally used for radio communications
- Class C
26. Power dissipation is the product of load output voltage and
- Load current
27. Sellen key filter is also known as
- VCVS filters
28. Reference component of improved shunt regulator
- Zener diode
29. Short circuit drops at terminals
- 0V
30. Has low input impedance
- Common – base
31. Does not have capacitance which affects by the miller effect
- Common- base
32. Why are the field poles and armature of dc machine laminated
- To reduce eddy current
33. Peak value of tunnel diode
- 600mV
34. Voltage regulation for LM7812
- 12V
35. Quality factor of crystal
- 20,000
36. If the rotation of a motor runs slower than normal this is due to
- Worn bearing
37. In emitter bias, the voltage across emitter resistor is the same as the voltage between emitter and
- Ground
38. Main feature of universal motor
- Highest kW/kg ratio
39. Single phase run motor
- Not self starting
40. If gate more negative in an N-channel FET, what happened to channel with depletion layer
- Shrinks
41. In the drain curve, the more horizontal the graph is
- Greater output impedance
42. Displays harmonic distortion
- Spectrum analyzer
43. Material used in tunnel diode semiconductor
- Gallium and germanium
44. In BJT amplifier, ____ gain has the value of less than 1 to 1000
- Current
45. Number of impurities of donor
- 5
46. Use to isolate the input from the output
- Optocoupler
47. Schottky diode operated in
- 20GHz
48. Typical value of the external frequency compensating capacitor of op-amps.
- 3.0 – 30 uF
49. Main feature of a universal motor
- Can operate in ac and dc
50. Characteristic of a BIFET
- Has high input impedance
51. Bulk resistance of 1N4001
- 0.23 ohms
52. The smallest switch off time
- LASCR
53. Maximum current rms rating of LASCR today
- 3A
54. Does not have a cathode terminal
- TRIAC
55. What amplifier has the lowest efficiency?
- Class A
56. Class B push-pull amplifier avoid
- Cross over distortion
57. E-MOSFET at cut-off is a
- Switching device
58. Monostable 555 timer has ___ stable state
- 1
59. Repulsion motor is equipped with ___
- Commutator
60. Control the open loops cut-off frequency
- Compensating capacitance
61. Howland produce ___
- Unidirectional single ended load current
62. Repulsion start induction run capacitor motor runs as a induction motor when
- Commutator segments are shorted
63. ICVS amplifier has no output voltage due to ____
- Shorted feed back resistor
64. Starting winding is placed on ____
- Stator
65. Source of mechanical force for rotating alternator, ac, dc, large and small ____
- prime mover
66. Approximation of maximally flat pass band
- Inverse chebysev
67. At low frequency coupling capacitor decreases ____
- Voltage gain
68. The gate current of a FET in dc analysis
- 0A
69. In audio system, reference accepted level ____
- 1mW
70. If the load is shorted the pass transistor has a lowest power dissipated when the regulator has ____
- Foldback limiting
71. To improve the high frequency response of an amplifier
- Shorten leads as much as possible
72. Carriers participate in injection process in unipolar device
- 1
73. Has negative resistance region
- Unijunction transistor
74. A transistor has how many layer
- 3
75. In foldback current limiting load resistance increases, load voltage ___
- Increases
76. Advantage of JFET is the fact that it is ___ controlled rather than ____ controlled
- dc, ac
77. Sallen key equal component second degree order determines
- Voltage gain
78. Single phase induction motor when removed from power supply it will only run on the ____ winding
- running
79. Small collector current with zero base current is due to the leakage current of
- Collector diode
80. In a dual diode NPN transistor the cathode can be found in
- Either of the emitter diode
81. Frequency operation of capacitor connected in parallel with ideal diode
- Very high frequency
82. In BJT, ____ frequency has two value important capacitance are the electrode between the internal
- High
83. In proper design, ___ can be introduced to the voltage controlled JFET resistor
- Thermistor
84. Zero crossing detector with hysteresis ____
- Has no feedback
85. In an ICVS op-amp load current approaches zero has load voltage approaches
- Infinity
86. If the load resistance is open the AC external emitter resistance is equal to
- DC Emmiter resistance
87. A permanent spilt single phase induction motor don’t have this ____
- Centrifugal switch
88. In VDB circuit collector resistance increases, collector voltage ____
- Increases
89. In the input RC circuit in first stage BJT, by how many does the base voltage leas input voltage of frequency larger than the cut-off frequency in no frequency region?
- About 90 degree
90. Capacitor start induction run is connected in series with ____ winding
- Starting
91. To increase the output voltage of a bulk switching regulator ____
- Increase the duty cycle
92. Protection from over power supply ____
- Crowbar
93. It determine the resonant frequency of a crystal ___
- The thickness and the size
94. In a closed loop voltage gain is equal to
- The feedback resistor divided by input resistance
95. To reverse the direction of rotation of the single phase induction motor
- Reversing connection in the starting winding
96. In VCVS circuit a decrease in output voltage has an increase in
- Error voltage
97. A two value capacitor for single phase motor
- Paper spaced oil filled capacitor
Post a Comment