ELEX FIGURES
問題一覧
1
If RL short-circuited:
the amplifier signal output would fall to zero
2
If R2 open-circuited:
the operating point would be affected and the signal distort
3
A voltmeter connected across RE reads zero. Most probably
RL has open-circuited
4
A voltmeter connected across RL reads zero. Most probably
the base collector junction of the transistor has gone open circuit
5
If RE short-circuited:
the load line would be affected
6
The load line represents a load resistor of
2kΩ
7
The no-signal collector dissipation for the operating point marked P is
18mW
8
The greatest permissible peak input current would be about
35 μA
9
The greatest possible peak output voltage would then be about
5.2 V
10
The power dissipated in the load resistor under no-signal conditions is:
18 mW
11
This circuit is a ________ oscillator.
phase-shift
12
Refer to the given figure. The resonant frequency is controlled by
C3, C4, C5, and L1.
13
Refer to this figure. This circuit is
an astable multivibrator.
14
This circuit is a ________ oscillator.
Colpitts
15
Refer to the given figure. This circuit is known as
a Hartley oscillator
16
Refer to the given figure. This circuit is known as
a Colpitts oscillator.
17
Refer to the given figure. This circuit is known as
a Clapp oscillator.
18
For the current-carrying conductor lying in the magnetic field shown, the direction of
the force on the conductor is:
downwards
19
For the current-carrying conductor lying in the magnetic field shown, the direction of
the current in the conductor is:
towards the viewer
20
Figure shows a rectangular coil of wire placed in a magnetic field and free to rotate about axis AB. If the current flows into the coil at C, the coil will:
remain in the vertical position
21
Figure shows a scale of a multi-range ammeter. What is the current indicated when switched to a 25A scale?
14A
22
Identify the problem in this motor control PLC
program:
Seal-in contact
23
Find the value of V if the current in the 3-ohm resistor is 0.
7.5V
24
What is the output waveform?
triangle wave
25
For a three-input OR gate, with the input waveforms as shown below, which output waveform is correct?
b
26
Which of the figures given below represents a NOR gate?
d
27
Which of the figures (a to d) is the DeMorgan equivalent of Figure (e)?
a
28
Which of the figures in figure (a to d) is equivalent to figure (e)?
c
29
For a 3-input NAND gate, with the input waveforms as shown below, which output waveform is correct?
c
30
Which of the figures given below represents a NAND gate?
a
31
Which timing diagram shown below is correct for an inverter?
b
32
Which of the figures given below represents an OR gate?
a
33
Which of the symbols shown below represents an AND gate?
d
34
For a three-input AND gate, with the input waveforms as shown below, which output waveform is correct?
c
35
What type of circuit is shown below, and how is the output ordinarily connected?
It is an open-collector gate. An external load must be connected between the output terminal and an appropriate supply voltage.
36
What type of circuit is represented in the given figure, and which statement best describes its operation?
It is a tristate inverter. When the ENABLE input is HIGH, the output is effectively an open circuit—it is neither LOW nor HIGH.
37
Refer to the given figure. What type of output arrangement is being used for the output?
Totem-pole
38
Refer the given figure. Which of the following describes the operation of the circuit?
A HIGH input turns Q1, Q2, and Q3 off, and Q4 is on.
39
What type of logic circuit is shown below and what logic function is being performed?
It is a CMOS NOR gate.
40
What type of circuit is shown below and which statement best describes its operation?
It is a CMOS inverter with tristate output.
41
Refer to the figure given below. What type of device is shown and what input levels are required to turn the LED off?
The device is an open-collector AND gate and requires both inputs to be HIGH in order to turn the LED off.
42
Refer to this figure. Assuming it is configured as an oscillator and if you desired to reduce the duty to less than 50%, the following circuit change would need to be made.
Connect a diode in parallel with R1.
43
Calculate the value of C1 = C2 for the Wien bridge oscillator to operate at a frequency of 20 kHz. Assume R1 = R2 = 50 kΩ and R3 = 3R4 = 600Ω?
159 pF
44
Given gm = 5000μ S, rd = 40kΩ, R = 10 kΩ, and A = 35. Determine the value of RD for oscillator operation at 1 kHz.
8.48 kΩ
45
Referring to this figure, calculate the voltage gain without feedback for the following circuit values: RD = 4 kΩ, RS = 1 kΩ, RF = 15 kΩ, and gm = μ5000 μS.
–20.0
46
This circuit is a ________ oscillator.
Wien bridge
47
Referring to this figure, calculate the voltage gain with the feedback for the following circuit values: RD = 4 kΩ, RS = 1 kΩ, RF = 15 kΩ, and gm = 5000 μS.
–8.57
48
Refer to the given figure. This circuit is known as
a Colpitts oscillator.
49
Referring to this figure, calculate the voltage gain with feedback Avf.
–4.17
50
Referring to this figure, calculate the amplification gain with feedback for the following circuit values: R1 = 80 kΩ, R2 = 20 kΩ, Ro = 10 kΩ, RD = 61 kΩ, and gm = 4000 μS.
–4.36
51
From the given circuit below, we can conclude that.
transistor is faulty
52
Consider a control system shown in given figure. For slight variation in G, the ratio of open loop sensitivity to closed loop sensitivity will be given by
1 : (1 + GH)^- 1
53
In the given figure, the curves 1, 2, 3 are respectively for
all pass, minimum phase and non-minimum phase functions
54
The block diagram of the given figure for:
On-off controller
55
A system has two poles as shown in the given figure. The zeros are at infinity. If input is unit step, the steady state output is
1
56
The system of the given figure
is unstable for all values of K
57
If block diagrams of the given figure (a) and (b) are to be equivalent, then
G2=G1
58
If block diagrams of the given figure (a) and (b) are to be equivalent, then
G2=G1
59
The given figure shows dB magnitude plots for type 0, type 1 and type 2 systems. Out of these
curves 1, 2, 3 are for type 0, 1, 2 systems respectively
60
The phase angle characteristic in the given figure is for
transport lag
61
In the given figure shows a root locus plot. Consider the following statements for this plot
1. The open loop system is a second order system
2. The system is overdamped for K > 1
3. The system is stable for all values of K
Which of the above statements are correct?
1, 3
62
A compensator has its pole and zero as shown in the given figure
lead compensator
63
The given figure shows a hybrid servosystem. The components 1, 2, 3, 4 are respectively
amplifier, demodulator, dc servomotor and load
64
For a second order system, the position of poles is shown in the given figure. This system is
underdamped
65
The pole zero plot of the given figure is for
minimum phase function
66
When a current source I is suddenly connected across a two terminal relaxed RC circuit at time t = 0, the voltage across the current source is shown in figure. The RC circuit is
a series combination of R and parallel combination of R and C
67
The degree of the nodes 1, 2, 3, 4 is
all 3
68
The circuit in figure will act as ideal current source with respect to terminals A and B when frequency is
1 rad/sec
69
The current wave shape shown in figure (1) is applied to a circuit element. The voltage across the element is shown in figure (2). The element is
C
70
In figure v1 = 8 V and v2 = 4 V. Which diode will conduct?
D1 only
71
Study the circuit of figure and examine the following statements
1. It is an active low pass finer.
2. It is a second order filter.
3. The change in gain is 40 dB/decade.
Which of the above statements are correct?
1, 2 and 3
72
The circuit diagram shown in the figure consists of transistors in;
parallel connection
73
Which point is the trailing edge of the repetitive pulse waveform in the given circuit?
Point A
74
Derive the Boolean expression for the logic circuit shown below:
C(A+B)DE
75
From the truth table below, determine the standard SOP expression.
x= A'B'C+A'BC+ABC'
76
The output of this circuit is always ________.
A'
77
The output of this circuit is always ________.
A
78
The purpose of the added RC section is to pass most of the dc component while reducing as much of the ac component as possible.
True
79
Refer to the given figure. If the zener diode had a rating of 1.7 V, the output voltage would be
8.36 V.
80
Refer to the given figure. This circuit operates at a ________ frequency, and its efficiency is ________.
high, high
81
Refer to the given figure. Determine the output voltage, VOUT.
20.2 V
82
Refer to the given figure. This circuit is known as
a shunt voltage regulator.
83
Refer to the given figure. This circuit is called
a step-down switching regulator.
84
In this improved series regulator circuit, which of the following components is the sampling circuit?
Resistors R1 and R2
85
Refer to the given figure. If the output of the circuit were to be a short circuit, what power rating would R1 need to have?
22.5 W
86
Refer to the given figure. This circuit is known as
a series-pass voltage regulator.
87
Refer to the given figure. The purpose for the zener diode D1 is
to supply a reference voltage.
88
Refer to the given figure. If the load is short-circuited, what would be the maximum current through R1?
1.5 A
89
Refer to the given figure. If a solder splash shorted the ends of R1 to each other,
the zener would fail.
90
In this op-amp series regulator circuit, which of the following components is the comparator circuit?
Op-amp
91
Refer to the given figure. The inductor and capacitor are used for
filtering the dc pulse output.
92
Refer to the given figure. If the BE junction of Q1 opens, the output voltage VOUT will
decrease
93
This circuit is an example of the ac equivalent of an RC filter.
False
94
Refer to the given figure. If the output voltage tends to decrease due to an increase in load current, the transistor will conduct for ________ time each cycle.
a longer
95
What regulated output voltage is provided for the following circuit elements: R1 = 15 k, R2 = 35 k, and VZ = 11.2 V?
17 V
96
Refer to the figure given below. The probable trouble, if any, indicated by these voltages is
the filter capacitor is shorted.
97
Refer to the figure given below. If the voltmeter across the transformer reads 0 V, the probable trouble, if any, would be
an open transformer secondary.
98
Refer to the figure given below. Which diode arrangement will supply a negative output voltage?
c
99
Which diode arrangement will supply a positive output voltage?
a
100
What is the logic function of this circuit?
Positive logic AND gate
問題一覧
1
If RL short-circuited:
the amplifier signal output would fall to zero
2
If R2 open-circuited:
the operating point would be affected and the signal distort
3
A voltmeter connected across RE reads zero. Most probably
RL has open-circuited
4
A voltmeter connected across RL reads zero. Most probably
the base collector junction of the transistor has gone open circuit
5
If RE short-circuited:
the load line would be affected
6
The load line represents a load resistor of
2kΩ
7
The no-signal collector dissipation for the operating point marked P is
18mW
8
The greatest permissible peak input current would be about
35 μA
9
The greatest possible peak output voltage would then be about
5.2 V
10
The power dissipated in the load resistor under no-signal conditions is:
18 mW
11
This circuit is a ________ oscillator.
phase-shift
12
Refer to the given figure. The resonant frequency is controlled by
C3, C4, C5, and L1.
13
Refer to this figure. This circuit is
an astable multivibrator.
14
This circuit is a ________ oscillator.
Colpitts
15
Refer to the given figure. This circuit is known as
a Hartley oscillator
16
Refer to the given figure. This circuit is known as
a Colpitts oscillator.
17
Refer to the given figure. This circuit is known as
a Clapp oscillator.
18
For the current-carrying conductor lying in the magnetic field shown, the direction of
the force on the conductor is:
downwards
19
For the current-carrying conductor lying in the magnetic field shown, the direction of
the current in the conductor is:
towards the viewer
20
Figure shows a rectangular coil of wire placed in a magnetic field and free to rotate about axis AB. If the current flows into the coil at C, the coil will:
remain in the vertical position
21
Figure shows a scale of a multi-range ammeter. What is the current indicated when switched to a 25A scale?
14A
22
Identify the problem in this motor control PLC
program:
Seal-in contact
23
Find the value of V if the current in the 3-ohm resistor is 0.
7.5V
24
What is the output waveform?
triangle wave
25
For a three-input OR gate, with the input waveforms as shown below, which output waveform is correct?
b
26
Which of the figures given below represents a NOR gate?
d
27
Which of the figures (a to d) is the DeMorgan equivalent of Figure (e)?
a
28
Which of the figures in figure (a to d) is equivalent to figure (e)?
c
29
For a 3-input NAND gate, with the input waveforms as shown below, which output waveform is correct?
c
30
Which of the figures given below represents a NAND gate?
a
31
Which timing diagram shown below is correct for an inverter?
b
32
Which of the figures given below represents an OR gate?
a
33
Which of the symbols shown below represents an AND gate?
d
34
For a three-input AND gate, with the input waveforms as shown below, which output waveform is correct?
c
35
What type of circuit is shown below, and how is the output ordinarily connected?
It is an open-collector gate. An external load must be connected between the output terminal and an appropriate supply voltage.
36
What type of circuit is represented in the given figure, and which statement best describes its operation?
It is a tristate inverter. When the ENABLE input is HIGH, the output is effectively an open circuit—it is neither LOW nor HIGH.
37
Refer to the given figure. What type of output arrangement is being used for the output?
Totem-pole
38
Refer the given figure. Which of the following describes the operation of the circuit?
A HIGH input turns Q1, Q2, and Q3 off, and Q4 is on.
39
What type of logic circuit is shown below and what logic function is being performed?
It is a CMOS NOR gate.
40
What type of circuit is shown below and which statement best describes its operation?
It is a CMOS inverter with tristate output.
41
Refer to the figure given below. What type of device is shown and what input levels are required to turn the LED off?
The device is an open-collector AND gate and requires both inputs to be HIGH in order to turn the LED off.
42
Refer to this figure. Assuming it is configured as an oscillator and if you desired to reduce the duty to less than 50%, the following circuit change would need to be made.
Connect a diode in parallel with R1.
43
Calculate the value of C1 = C2 for the Wien bridge oscillator to operate at a frequency of 20 kHz. Assume R1 = R2 = 50 kΩ and R3 = 3R4 = 600Ω?
159 pF
44
Given gm = 5000μ S, rd = 40kΩ, R = 10 kΩ, and A = 35. Determine the value of RD for oscillator operation at 1 kHz.
8.48 kΩ
45
Referring to this figure, calculate the voltage gain without feedback for the following circuit values: RD = 4 kΩ, RS = 1 kΩ, RF = 15 kΩ, and gm = μ5000 μS.
–20.0
46
This circuit is a ________ oscillator.
Wien bridge
47
Referring to this figure, calculate the voltage gain with the feedback for the following circuit values: RD = 4 kΩ, RS = 1 kΩ, RF = 15 kΩ, and gm = 5000 μS.
–8.57
48
Refer to the given figure. This circuit is known as
a Colpitts oscillator.
49
Referring to this figure, calculate the voltage gain with feedback Avf.
–4.17
50
Referring to this figure, calculate the amplification gain with feedback for the following circuit values: R1 = 80 kΩ, R2 = 20 kΩ, Ro = 10 kΩ, RD = 61 kΩ, and gm = 4000 μS.
–4.36
51
From the given circuit below, we can conclude that.
transistor is faulty
52
Consider a control system shown in given figure. For slight variation in G, the ratio of open loop sensitivity to closed loop sensitivity will be given by
1 : (1 + GH)^- 1
53
In the given figure, the curves 1, 2, 3 are respectively for
all pass, minimum phase and non-minimum phase functions
54
The block diagram of the given figure for:
On-off controller
55
A system has two poles as shown in the given figure. The zeros are at infinity. If input is unit step, the steady state output is
1
56
The system of the given figure
is unstable for all values of K
57
If block diagrams of the given figure (a) and (b) are to be equivalent, then
G2=G1
58
If block diagrams of the given figure (a) and (b) are to be equivalent, then
G2=G1
59
The given figure shows dB magnitude plots for type 0, type 1 and type 2 systems. Out of these
curves 1, 2, 3 are for type 0, 1, 2 systems respectively
60
The phase angle characteristic in the given figure is for
transport lag
61
In the given figure shows a root locus plot. Consider the following statements for this plot
1. The open loop system is a second order system
2. The system is overdamped for K > 1
3. The system is stable for all values of K
Which of the above statements are correct?
1, 3
62
A compensator has its pole and zero as shown in the given figure
lead compensator
63
The given figure shows a hybrid servosystem. The components 1, 2, 3, 4 are respectively
amplifier, demodulator, dc servomotor and load
64
For a second order system, the position of poles is shown in the given figure. This system is
underdamped
65
The pole zero plot of the given figure is for
minimum phase function
66
When a current source I is suddenly connected across a two terminal relaxed RC circuit at time t = 0, the voltage across the current source is shown in figure. The RC circuit is
a series combination of R and parallel combination of R and C
67
The degree of the nodes 1, 2, 3, 4 is
all 3
68
The circuit in figure will act as ideal current source with respect to terminals A and B when frequency is
1 rad/sec
69
The current wave shape shown in figure (1) is applied to a circuit element. The voltage across the element is shown in figure (2). The element is
C
70
In figure v1 = 8 V and v2 = 4 V. Which diode will conduct?
D1 only
71
Study the circuit of figure and examine the following statements
1. It is an active low pass finer.
2. It is a second order filter.
3. The change in gain is 40 dB/decade.
Which of the above statements are correct?
1, 2 and 3
72
The circuit diagram shown in the figure consists of transistors in;
parallel connection
73
Which point is the trailing edge of the repetitive pulse waveform in the given circuit?
Point A
74
Derive the Boolean expression for the logic circuit shown below:
C(A+B)DE
75
From the truth table below, determine the standard SOP expression.
x= A'B'C+A'BC+ABC'
76
The output of this circuit is always ________.
A'
77
The output of this circuit is always ________.
A
78
The purpose of the added RC section is to pass most of the dc component while reducing as much of the ac component as possible.
True
79
Refer to the given figure. If the zener diode had a rating of 1.7 V, the output voltage would be
8.36 V.
80
Refer to the given figure. This circuit operates at a ________ frequency, and its efficiency is ________.
high, high
81
Refer to the given figure. Determine the output voltage, VOUT.
20.2 V
82
Refer to the given figure. This circuit is known as
a shunt voltage regulator.
83
Refer to the given figure. This circuit is called
a step-down switching regulator.
84
In this improved series regulator circuit, which of the following components is the sampling circuit?
Resistors R1 and R2
85
Refer to the given figure. If the output of the circuit were to be a short circuit, what power rating would R1 need to have?
22.5 W
86
Refer to the given figure. This circuit is known as
a series-pass voltage regulator.
87
Refer to the given figure. The purpose for the zener diode D1 is
to supply a reference voltage.
88
Refer to the given figure. If the load is short-circuited, what would be the maximum current through R1?
1.5 A
89
Refer to the given figure. If a solder splash shorted the ends of R1 to each other,
the zener would fail.
90
In this op-amp series regulator circuit, which of the following components is the comparator circuit?
Op-amp
91
Refer to the given figure. The inductor and capacitor are used for
filtering the dc pulse output.
92
Refer to the given figure. If the BE junction of Q1 opens, the output voltage VOUT will
decrease
93
This circuit is an example of the ac equivalent of an RC filter.
False
94
Refer to the given figure. If the output voltage tends to decrease due to an increase in load current, the transistor will conduct for ________ time each cycle.
a longer
95
What regulated output voltage is provided for the following circuit elements: R1 = 15 k, R2 = 35 k, and VZ = 11.2 V?
17 V
96
Refer to the figure given below. The probable trouble, if any, indicated by these voltages is
the filter capacitor is shorted.
97
Refer to the figure given below. If the voltmeter across the transformer reads 0 V, the probable trouble, if any, would be
an open transformer secondary.
98
Refer to the figure given below. Which diode arrangement will supply a negative output voltage?
c
99
Which diode arrangement will supply a positive output voltage?
a
100
What is the logic function of this circuit?
Positive logic AND gate