WJEC 2014 Online Exam Review
GCSE Electronics Unit E2 4162-01
All Candidates' performance across questions
Question Title
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
N
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
499
Mean
0.6
1.3
2.2
2
0.7
2
0.5
1.1
2.7
1.5
2
1.7
1.7
2.3
0.9
2.1
1.3
1.6
1
1.6
2.1
1.2
SD
0.5
0.7
0.9
1.1
0.5
1
0.5
0.8
0.8
1.2
1.2
0.9
1.1
1.5
1.2
1.5
0.8
1
0.8
1.3
1.6
1
Max Mark
1
2
3
3
1
3
1
2
3
3
3
3
4
4
3
4
2
3
2
3
5
2
FF
55.9
65.6
73.4
67.4
68.1
66.6
50.1
56.8
89.4
51.2
65.3
57.2
41.3
58.6
30.9
52.5
67
52.6
52.4
53.3
41.6
58.4
Attempt %
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
Question
GCSE Electronics Unit E2 4162-01
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
58.4
53.3
52.4
52.6
67
52.5
58.6
57.2
65.3
51.2
56.8
50.1
66.6
68.1
67.4
73.4
65.6
55.9
41.6
30.9
0
10
20
30
41.3
40
50
60
Facility Factor %
70
89.4
80
90
100
10
18
20
11
Examiner
only
10.A rising-edge triggered D-type flip-flop is used for data transfer.
Complete the graphs to show the Q and Q outputs.
[3]
Logic
1
Clock
0
Time
Logic
1
Data
0
Time
Logic
1
Q
0
Time
Logic
1
Q
0
Time
© WJEC CBAC Ltd.
(4162-01)
Turn over.
41 6 2
0 1 0 0 11
23
18.
Examiner
only
(a) Which one of the following is the best description of the term bandwidth?
(Tick (√) the correct answer.)
[1]
The maximum frequency of the input signal.
The input voltage range that can be amplified successfully.
The range of frequencies that produces more than a specified voltage gain.
The power supply voltage that produces optimum output voltage for a given signal.
Voltage gain
100
80
60
40
20
0
0
1 000 2 000
3 000 4 000
5 000 6 000
Frequency / Hz
(b)
Use the graph to find:
[2]
(i) the voltage gain at which the bandwidth should be measured;
Voltage gain =
................................................
(ii) the bandwidth.
Bandwidth =
© WJEC CBAC Ltd.
(4162-01)
...............................................
Hz
Turn over.
24
Examiner
only
20. A Schmitt inverter is connected to a temperature sensing unit.
Temperature
sensing unit
Schmitt
inverter
The circuit runs on a 15 V power supply.
Part of the data sheet for the Schmitt inverter is shown below.
When connected to a 15 V supply:
• Logic 0 output = 0 V;
• Logic 1 output = 15 V;
• The output changes from logic 1 to logic 0 when
a rising input voltage reaches 10 V;
• The output changes from logic 0 to logic 1
when a falling input voltage reaches 5 V.
© WJEC CBAC Ltd.
(4162-01)