1. what type of voltage is supplied by a rectifier?

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1. What type of 1. What type of voltage is supplied by voltage is supplied by a rectifier? a rectifier?

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1. What type of voltage is 1. What type of voltage is supplied by a rectifier?supplied by a rectifier?

Pulsating DC voltage.Pulsating DC voltage.

2. What type of voltage is 2. What type of voltage is usually required by most usually required by most electronic equipment?electronic equipment?

Smooth DC voltageSmooth DC voltage

3. What is the purpose of a 3. What is the purpose of a filter used in a rectifier filter used in a rectifier

circuit?circuit?

To smooth out the pulsating To smooth out the pulsating DC voltage.DC voltage.

4. What do you call the filter that 4. What do you call the filter that uses a capacitor as the first uses a capacitor as the first

component following the rectifier component following the rectifier output?output?

Capacitor input filter.Capacitor input filter.

5. What does a capacitor 5. What does a capacitor oppose?oppose?

Change in voltage.Change in voltage.

6. What do you call the filter that 6. What do you call the filter that uses a coil as the first uses a coil as the first

component following the rectifier component following the rectifier output?output?

Choke input filter.Choke input filter.

7. What does a choke filter 7. What does a choke filter oppose?oppose?

Change in current.Change in current.

8. When is the pi filter with 8. When is the pi filter with the resistor in it mainly used?the resistor in it mainly used?

Low current applications.Low current applications.

9. What is the symbol for pi?9. What is the symbol for pi?

10. Which is the most common 10. Which is the most common filter configuration found in filter configuration found in

power supplies?power supplies?

A pi filter with a coil.A pi filter with a coil.

11. What is a filter circuit?11. What is a filter circuit?

It is a network of resistors It is a network of resistors and inductors or capacitors.and inductors or capacitors.

12. What does “filter” mean in 12. What does “filter” mean in electronics?electronics?

To filter means to oppose or To filter means to oppose or reject voltages and currents of reject voltages and currents of certain frequencies while also certain frequencies while also offering little opposition to or offering little opposition to or

passing of voltages and passing of voltages and currents of other frequencies.currents of other frequencies.

13. What do filter circuits block?13. What do filter circuits block?

Certain frequencies.Certain frequencies.

14. What does an RL circuit 14. What does an RL circuit contain?contain?

Both resistance and inductance.Both resistance and inductance.

15. What opposes current flow 15. What opposes current flow in an RL circuit?in an RL circuit?

Resistance and inductive Resistance and inductive reactance.reactance.

16. What is impedance?16. What is impedance?

The total opposition to current The total opposition to current flow in RL circuits.flow in RL circuits.

17. What do you call a filter circuit 17. What do you call a filter circuit that contains resistance and that contains resistance and

capacitance?capacitance?

An RC filter circuit.An RC filter circuit.

18. What is another term for 18. What is another term for “cut-off frequency”?“cut-off frequency”?

Half-power point.Half-power point.

19. If input frequency decreases in 19. If input frequency decreases in an RL circuit, what happens to an RL circuit, what happens to

voltage across the resistor?voltage across the resistor?

Voltage across the resistor Voltage across the resistor increases.increases.

20. What is another name for a 20. What is another name for a high-frequency discriminator?high-frequency discriminator?

A low-pass filter.A low-pass filter.

21. What is a high-pass filter?21. What is a high-pass filter?

A filter that passes high frequencies A filter that passes high frequencies and discriminates or blocks low and discriminates or blocks low

frequencies.frequencies.

22. What is a low-pass filter?22. What is a low-pass filter?

A filter that passes low frequencies A filter that passes low frequencies and discriminates or blocks the and discriminates or blocks the

high frequencies.high frequencies.

23. How can a capacitor act as a 23. How can a capacitor act as a high-pass filter in one instance and high-pass filter in one instance and

as a low-pass filter in another as a low-pass filter in another instance?instance?

It is determined by the capacitor’s It is determined by the capacitor’s position either across a load or in position either across a load or in

series with a load.series with a load.

24. What do you call a speaker 24. What do you call a speaker that produces low-frequency that produces low-frequency

sounds?sounds?

A woofer.A woofer.

25. What type of speaker is 25. What type of speaker is wired across a resistor?wired across a resistor?

A woofer.A woofer.

26. What is a tweeter used 26. What is a tweeter used for?for?

High-frequency sounds.High-frequency sounds.

27. What is the final stage of 27. What is the final stage of a power supply?a power supply?

The voltage regulator circuit.The voltage regulator circuit.

28. What is the function of 28. What is the function of the voltage regulator?the voltage regulator?

It keeps the output voltage at a It keeps the output voltage at a constant level under varying constant level under varying

loads.loads.

29. What are some reasons why 29. What are some reasons why voltage might vary in a circuit?voltage might vary in a circuit?

Input line voltage may vary; load Input line voltage may vary; load on the power supply might on the power supply might

change; and components could change; and components could be old.be old.

30. What is the simplest type 30. What is the simplest type of voltage regulator?of voltage regulator?

A series regulator.A series regulator.

31. Which type of voltage 31. Which type of voltage regulator has the regulating regulator has the regulating device connected in series?device connected in series?

A series regulator.A series regulator.

32. Which regulator has the 32. Which regulator has the regulating device connected in regulating device connected in

parallel with the load?parallel with the load?

A shunt regulator.A shunt regulator.

33. In a shunt regulator, how is 33. In a shunt regulator, how is the regulating device the regulating device

connected?connected?

In parallel with the load.In parallel with the load.

34. In a shunt regulator, what is 34. In a shunt regulator, what is the voltage across the RV plus the voltage across the RV plus

the voltage across RS equal to?the voltage across RS equal to?

The total DC voltage from the The total DC voltage from the filter.filter.

35. What is the only adjustment 35. What is the only adjustment that can be made in a shunt that can be made in a shunt

resistor?resistor?

Adjustment to the variable Adjustment to the variable resistor.resistor.

36. What happens to the 36. What happens to the voltage drop across RS when voltage drop across RS when there is an increase in current there is an increase in current

through RS?through RS?

The voltage drop across RS The voltage drop across RS will increase.will increase.

37. What type of diode is used 37. What type of diode is used as an automatic regulating as an automatic regulating

device?device?

A zener diode.A zener diode.

38. Why is a zener diode used 38. Why is a zener diode used instead of a variable resistor in instead of a variable resistor in

most regulators?most regulators?

Because the input voltage of a Because the input voltage of a variable resistor will fluctuate variable resistor will fluctuate too rapidly to be controlled by too rapidly to be controlled by

hand.hand.

39. What voltage level does a 39. What voltage level does a zener diode maintain?zener diode maintain?

A constant voltage level as long A constant voltage level as long as the zener continues to as the zener continues to

conduct.conduct.

40. What is the output of a 40. What is the output of a zener diode?zener diode?

Zener voltage.Zener voltage.

41. What is the purpose of a 41. What is the purpose of a voltage divider?voltage divider?

It makes it possible to obtain It makes it possible to obtain more than one voltage from a more than one voltage from a

single power source.single power source.

42. What is the simplest form 42. What is the simplest form of a voltage divider?of a voltage divider?

A simple series-parallel A simple series-parallel circuit.circuit.

43. What is a voltage divider 43. What is a voltage divider composed of?composed of?

A simple series-parallel circuit A simple series-parallel circuit with a number of resistors in with a number of resistors in series with a power source.series with a power source.

44. What formula do you use to 44. What formula do you use to determine amps when you know determine amps when you know

the resistance and voltage?the resistance and voltage?

Ohm’s Law I = E/ROhm’s Law I = E/R

45. What is a no-load 45. What is a no-load condition?condition?

A condition when no load or A condition when no load or energy using device is energy using device is

connected to the voltage divider.connected to the voltage divider.

46. What changes the output 46. What changes the output of a voltage divider?of a voltage divider?

Connecting a load to a voltage Connecting a load to a voltage divider changes the output.divider changes the output.

47. What is the purpose of a 47. What is the purpose of a bleeder resistor when bleeder resistor when

equipment is turned off.equipment is turned off.

To provide a discharge path To provide a discharge path for the filter capacitor voltage.for the filter capacitor voltage.

48. What is bleeder current in 48. What is bleeder current in a voltage divider?a voltage divider?

The small amount of current in a The small amount of current in a voltage divider that flows voltage divider that flows

through the bleeder resistor and through the bleeder resistor and aids in voltage regulation.aids in voltage regulation.

49. What type of voltages can 49. What type of voltages can be obtained from a single be obtained from a single

voltage divider?voltage divider?

Both positive and negative Both positive and negative voltage.voltage.

50. What happens to total 50. What happens to total output voltage when a load is output voltage when a load is

connected to a voltage divider?connected to a voltage divider?

The voltage decreases.The voltage decreases.

51. What provides the correct 51. What provides the correct amount of voltage and current amount of voltage and current

to operate an electronic to operate an electronic system?system?

A power supply.A power supply.

52. What is the most common 52. What is the most common way of connecting the line way of connecting the line voltage to a power supply?voltage to a power supply?

By using a standard plug.By using a standard plug.

53. What are the first two 53. What are the first two functions of the input stage of functions of the input stage of

the power supply?the power supply?

To provide a method of coupling To provide a method of coupling the AC line into the power the AC line into the power

supply and to provide overload supply and to provide overload protection.protection.

54. What can provide 54. What can provide overload protection to a overload protection to a

power supply?power supply?

A fuse or circuit breaker.A fuse or circuit breaker.

55. How does a fuse provide 55. How does a fuse provide protection to a circuit?protection to a circuit?

A fuse will melt, opening the A fuse will melt, opening the circuit, when it is overheated.circuit, when it is overheated.

56. What is the advantage of 56. What is the advantage of using a circuit breaker instead using a circuit breaker instead

of a fuse?of a fuse?

A circuit breaker can be reset A circuit breaker can be reset and used again, but a fuse must and used again, but a fuse must

be replaced.be replaced.

57. What are the last two 57. What are the last two functions of the input stage of a functions of the input stage of a

power supply?power supply?

To provide an indication that To provide an indication that power is on and to provide a power is on and to provide a

means of turning the power on means of turning the power on and off.and off.

58. What is the second stage of 58. What is the second stage of a power supply?a power supply?

The conversion stage.The conversion stage.

59. Which substage steps up or 59. Which substage steps up or steps down AC line voltage?steps down AC line voltage?

The transformer secondary.The transformer secondary.

60. What is the purpose of the 60. What is the purpose of the filter substage?filter substage?

The filter substage smooths out the The filter substage smooths out the pulsating DC into smooth DC.pulsating DC into smooth DC.

61. What does the rectifier do in the 61. What does the rectifier do in the conversion stage of the power conversion stage of the power

supply?supply?

The rectifier receives the voltage The rectifier receives the voltage from the transformer secondary from the transformer secondary and converts it to DC voltage.and converts it to DC voltage.

62. What are the three substages in 62. What are the three substages in the conversion stage of the power the conversion stage of the power

supply?supply?

Transformer secondary, rectifier, Transformer secondary, rectifier, and filter.and filter.

63. What is the last stage in 63. What is the last stage in the power supply?the power supply?

The output stage.The output stage.

64. What is the basic function of 64. What is the basic function of this final stage of the power this final stage of the power

supply?supply?

Maintain a steady DC output.Maintain a steady DC output.

65. What are the three stages 65. What are the three stages in a power supply?in a power supply?

Input, conversion, and output.Input, conversion, and output.

66. What is the symbol for a 66. What is the symbol for a fuse?fuse?

67. What is the symbol for a 67. What is the symbol for a circuit breaker?circuit breaker?

68. What is the symbol for a 68. What is the symbol for a standard plug?standard plug?

69. What do you call a non-69. What do you call a non-rotating device used for rotating device used for

producing alternating current producing alternating current from a direct current supply?from a direct current supply?

Oscillator.Oscillator.

70. Why is the word “non-70. Why is the word “non-rotating” used in describing an rotating” used in describing an

oscillator?oscillator?

So the word will not be So the word will not be confused with alternator or confused with alternator or

generator.generator.

71. How do you refer to 71. How do you refer to something that moves back and something that moves back and

forth in a uniform manner?forth in a uniform manner?

It is said to oscillate.It is said to oscillate.

72. What conditions must exist 72. What conditions must exist for something to oscillate?for something to oscillate?

There must be a back and forth There must be a back and forth motion and the period for the motion and the period for the

back and forth motion must be back and forth motion must be the same.the same.

73. What are the three essential 73. What are the three essential sections of an oscillator circuit?sections of an oscillator circuit?

Feedback, amplifier, and Feedback, amplifier, and frequency determining device.frequency determining device.

74. Which section of the 74. Which section of the oscillator develops the desired oscillator develops the desired

AC frequency?AC frequency?

The frequency determining The frequency determining device or tank circuit.device or tank circuit.

75. What does the tank circuit 75. What does the tank circuit contain?contain?

A capacitor and an inductor.A capacitor and an inductor.

76. What does the tank circuit 76. What does the tank circuit have to do to continue have to do to continue

oscillating?oscillating?

It has to have a voltage push.It has to have a voltage push.

77. What is another term for 77. What is another term for positive feedback in an positive feedback in an

oscillator?oscillator?

Regenerative feedback.Regenerative feedback.

78. What actually does the 78. What actually does the oscillating in an oscillator?oscillating in an oscillator?

The tank circuit.The tank circuit.

79. What section of the 79. What section of the oscillator amplifies the tank oscillator amplifies the tank

circuit output to a usable level?circuit output to a usable level?

The amplifier circuit.The amplifier circuit.

80. Why does the feedback 80. Why does the feedback circuit return part of the circuit return part of the

oscillation output signal back oscillation output signal back into the tank circuit?into the tank circuit?

To insure sustained To insure sustained oscillation.oscillation.

81. What part of the oscillator 81. What part of the oscillator replaces the energy lost in the replaces the energy lost in the

tank circuit?tank circuit?

The feedback circuit.The feedback circuit.

82. What happens if one stage 82. What happens if one stage or section of the oscillator fails or section of the oscillator fails

to function?to function?

It totally disables oscillation.It totally disables oscillation.

83. What do you do when 83. What do you do when you troubleshoot a circuit?you troubleshoot a circuit?

You locate and correct any You locate and correct any malfunction in the circuit.malfunction in the circuit.

84. What is a short circuit?84. What is a short circuit?

A defect in a circuit that permits A defect in a circuit that permits current to flow around all or part current to flow around all or part

of the load.of the load.

85. What has happened to 85. What has happened to equipment that has equipment that has

malfunctioned?malfunctioned?

It does not operate normally.It does not operate normally.

86. What do we mean by an 86. What do we mean by an open circuit?open circuit?

A circuit that does not provide a A circuit that does not provide a complete path for current flow.complete path for current flow.

87. What is a direct short?87. What is a direct short?

A condition in a circuit that A condition in a circuit that occurs when a conducting occurs when a conducting

material forms a path directly material forms a path directly between the terminals of a between the terminals of a

source.source.

88. What is a partial short?88. What is a partial short?

A condition that exists when a A condition that exists when a short circuit bypasses only part short circuit bypasses only part of the normal load in a circuit.of the normal load in a circuit.

89. What is the function of a 89. What is the function of a fuse in a circuit?fuse in a circuit?

A safety device used to protect A safety device used to protect a circuit and electrical a circuit and electrical

components against excessive components against excessive amounts of current.amounts of current.

90. How are fuses rated?90. How are fuses rated?

In amperes.In amperes.

91. What has happened to a 91. What has happened to a circuit when a fuse has blown?circuit when a fuse has blown?

The circuit opens.The circuit opens.

92. What instruments can be 92. What instruments can be used in locating shorts?used in locating shorts?

A voltmeter or an ohmmeter.A voltmeter or an ohmmeter.

93. What is the first step in 93. What is the first step in using an ohmmeter?using an ohmmeter?

Make sure the circuit is de-Make sure the circuit is de-energized.energized.

94. What do we mean by the 94. What do we mean by the term “blow fuse”?term “blow fuse”?

When a fuse burns out we When a fuse burns out we say it is blown.say it is blown.

95. What can cause an open 95. What can cause an open circuit?circuit?

A blown fuse, dirt on switch A blown fuse, dirt on switch contacts, broken wires, or contacts, broken wires, or burned out components.burned out components.

96. What normally causes 96. What normally causes short circuits?short circuits?

Broken or cut insulation wires, Broken or cut insulation wires, loose tools, or loose pieces or loose tools, or loose pieces or

wire.wire.

97. What is a defective 97. What is a defective switch?switch?

A switch that is not working A switch that is not working correctly.correctly.

98. What is an important safety 98. What is an important safety rule for you to remember when rule for you to remember when you are working on any type of you are working on any type of

electronic equipment?electronic equipment?

Be careful.Be careful.

99. What causes electric 99. What causes electric shock?shock?

Electric current flowing Electric current flowing through an individual’s body.through an individual’s body.

100. What is a “hot” wire?100. What is a “hot” wire?

A conductor through which A conductor through which current is flowing.current is flowing.

101. How can an electric 101. How can an electric shock kill an individual?shock kill an individual?

By stopping his or her heart, By stopping his or her heart, breathing, or both.breathing, or both.

102. What could cause an 102. What could cause an individual’s body to have a low individual’s body to have a low resistance to electric shock?resistance to electric shock?

If his or her skin is moist or If his or her skin is moist or there are cuts on his or her there are cuts on his or her

body.body.

103. What is artificial 103. What is artificial respiration?respiration?

A mechanical or manual means A mechanical or manual means or inducing breathing in or inducing breathing in

someone when breathing has someone when breathing has stopped.stopped.

104. What is the first thing that 104. What is the first thing that you must do if you see you must do if you see

someone receive an electric someone receive an electric shock?shock?

Turn off the high voltage.Turn off the high voltage.

105. When would you stop 105. When would you stop administering artificial administering artificial

respiration?respiration?

When the victim starts to breath When the victim starts to breath or when professional medical or when professional medical

assistance arrives.assistance arrives.

106. Why is it important to have 106. Why is it important to have adequate light when you are adequate light when you are

working on an energized circuit?working on an energized circuit?

So you can see clearly to So you can see clearly to perform your job.perform your job.

107. What should you stand on 107. What should you stand on when you work on energized when you work on energized

equipment?equipment?

A rubber mat, a large piece of A rubber mat, a large piece of canvas or wood.canvas or wood.