# Electrical Technology Grade 12 NSC November 2020 QP (Eng)

> Grade 12 Electrical Technology question paper from the NSC November Exam 2020 (English), 24 pages. Read online or download the free PDF.

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- Updated: 2026-09-27
- Subject: Electrical Technology
- Grade: Grade 12
- Document type: Question paper
- Year: 2020
- Exam period: NSC November Exam
- Curriculum: CAPS
- Pages: 24

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Electrical Technology · Grade 12 · NSC November Exam · 2020. Question paper, 24 pages. Read online or download the PDF.

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                                  GRAAD 12

                           SENIOR CERTIFICATE/
                       NATIONAL SENIOR CERTIFICATE

                                    GRADE 12

                     ELECTRICAL TECHNOLOGY: ELECTRONICS

                                  NOVEMBER 2020

MARKS: 200

TIME: 3 hours

        This question paper consists of 18 pages, a 1-page formula sheet and
                                 5 answer sheets.

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INSTRUCTIONS AND INFORMATION

1.        This question paper consists of FIVE questions.

2.        Answer ALL the questions.

3.        Answer QUESTIONS 2.1.1, 2.2.4, 4.3.2, 4.4.2, 4.6.2, 4.8.2 and 4.8.3 on the
          attached ANSWER SHEETS.

4.        Write your CENTRE NUMBER and EXAMINATION NUMBER on every
          ANSWER SHEET and staple them to your ANSWER BOOK, whether you
          have not used them or not.

5.        Sketches and diagrams must be large, neat and FULLY LABELLED.

6.        Show ALL calculations and round off answers correctly to TWO decimal
          places.

7.        Number the answers correctly according to the numbering system used in
          this question paper.

8.        You may use a non-programmable calculator.

9         Calculations must include:

          9.1.        Formulae and manipulations where needed

          9.2         Correct replacement of values

          9.3         Correct answer and relevant units where applicable

10.       A formula sheet is attached at the end of this question paper.

11.       Write neatly and legibly.

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QUESTION 1: OCCUPATIONAL HEALTH AND SAFETY

1.1       Define health and safety equipment.                                                               (2)

1.2       Name ONE human right in the workplace.                                                            (1)

1.3       Name TWO incidents that should be reported to inspectors at the workplace.                        (2)

1.4       State THREE types of victimisation by an employer that are forbidden.                             (3)

1.5       Describe how the master switch in a workshop contributes to safety.                               (2)
                                                                                                            [10]

QUESTION 2: RLC CIRCUITS

2.1       Two AC voltages, VR and VX, each have maximum values of VR = 20 V and
          VX = 30 V respectively.

          2.1.1        Draw the phasor diagram (NOT to scale) on the ANSWER SHEET
                       for QUESTION 2.1.1 if VX lags VR by 35°.                                             (2)

          2.1.2        Explain whether      the    voltages      represent   an    RL     circuit   or
                       an RC circuit.                                                                       (2)

2.2       The RLC series circuit in FIGURE 2.2 below consists of a resistor of 15 Ω, an
          inductance of 20 mH and a capacitive reactance of 25 Ω. The components
          are all connected in series across a 150 V/60 Hz AC supply. Answer the
          questions that follow.

                               R = 15 Ω              L = 20 mH               XC = 25 Ω

                             VR = 98 V               VL = 49 V                    VC

                      IT = 6,5 A

                                                      150V/60Hz

                                     FIGURE 2.2: RLC SERIES CIRCUIT
          Given:
          R       =   15 Ω
          L       =   20 mH
          XC      =   25 Ω
          VT      =   150 V
          f       =   60 Hz
          IT      =   6,5 A

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          2.2.1       Calculate the inductive reactance of the inductor.                           (3)

          2.2.2       Calculate the voltage drop across the capacitor.                             (3)

          2.2.3       Indicate whether the supply voltage is lagging or leading. Motivate
                      your answer.                                                                 (2)

          2.2.4       Draw the phasor diagram of the circuit on the ANSWER SHEET for
                      QUESTION 2.2.4.                                                              (5)

2.3       Refer to FIGURE 2.3 below and answer the questions that follow.

                               IC

                                                              IR           VT

                                IL

                                     FIGURE 2.3: PHASOR DIAGRAM

          2.3.1       Identify the phasor diagram in FIGURE 2.3.                                   (2)

          2.3.2       State why the supply voltage is used as the reference in the phasor
                      diagram.                                                                     (1)

          2.3.3       Explain the relationship between the total current and the
                      impedance in a parallel resonant circuit.                                    (2)

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2.4       Refer to FIGURE 2.4 below and answer the questions that follow.

                            R = 20 Ω              L = 300 mH         C = 150 µF

                                                      VS
                                     FIGURE 2.4: RLC SERIES CIRCUIT

          Given:

          R     = 20 Ω
          L     = 300 mH
          C     = 150 µF

          2.4.1       Calculate the resonant frequency.                                              (3)

          2.4.2       Calculate the quality factor of the circuit.                                   (3)

          2.4.3       Determine the impedance of the circuit at resonance. Motivate your
                      answer.                                                                        (2)

          2.4.4       Calculate the value of the capacitance required for the circuit in
                      FIGURE 2.4 to resonate at 2 kHz.                                               (3)

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2.5       FIGURE 2.5 below shows the Q-factor characteristic curve of an RLC circuit,
          NOT to scale. Q1, Q2 and Q3 indicate how a change in the L/C ratio affects the
          Q-factor of a resonant circuit. Answer the questions that follow.

                                                                    Q1

             Q1 0,707 Imax

                                                                          Q2

             Q2 0,707 Imax

                                                                                Q3
             Q3 0,707 Imax

                                                 25    30     35   40
                                                                   45                 f (kHz)
                        FIGURE 2.5: Q-FACTOR CHARACTERISTIC CURVE

          2.5.1        Identify the curve with the highest selectivity.                              (1)

          2.5.2        Calculate the resonant frequency for response curve Q 1.                      (3)

          2.5.3        Calculate the quality factor for Q1.                                          (3)
                                                                                                     [40]

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QUESTION 3: SEMICONDUCTOR DEVICES
3.1       FIGURE 3.1 below shows a cross-section of the construction of an
          enhancement mode MOSFET. Answer the questions that follow.

                                       A            B              C

                                                                           Silicon-dioxide
                                                                              insulation

                                                                             Enhanced
                                                                              channel
                                               P-substrate

                            FIGURE 3.1: ENHANCEMENT MODE MOSFET
          3.1.1        Identify A, B and C.                                                        (3)
          3.1.2        Indicate whether the enhanced channel consists of P-type or
                       N-type material.                                                            (1)
          3.1.3        State what will happen to the current between terminal A and
                       terminal C if the voltage on terminal B is 0 V.                             (1)
          3.1.4        FIGURE 3.1.4 below shows the various FET symbols. Identify the
                       components represented by symbols A, C and E.

                                           D                       D                D

                                                                       G
                           G                            G

                                           S                       S                S
                                 (A)                         (B)              (C)
                                           D                       D                D

                                                                       G
                          G
                                                        G

                                           S                       S                S

                                 (D)                         (E)              (F)
                                               FIGURE 3.1.4: FET SYMBOLS                           (3)

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3.2       Explain the term negative resistance with reference to the UJT.                          (2)

3.3       Refer to FIGURE 3.3 below and answer the questions that follow.

                                                                      + VCC

                                      R1                RC
                                                                              Output
                                                                  C

                     Input                         T1
                                C1             B
                                                             T2
                                                                  E

                                      R2                RE            CE

                                                                       0V

                                     FIGURE 3.3: DARLINGTON PAIR

          3.3.1        Explain why the Darlington pair is preferred to a single transistor
                       for this circuit.                                                           (2)

          3.3.2        Explain why the Darlington pair needs a minimum of 1,2 V to 1,4 V
                       across its base-emitter terminals to operate.                               (3)

3.4       Refer to FIGURE 3.4 below and answer the questions that follow.

                                                         V+

                         Non-inverting input
                                                                       Output
                             Inverting input

                                                             V-

                                           FIGURE 3.4: OP-AMP

          3.4.1        Name TWO characteristics of an ideal op-amp.                                (2)

          3.4.2        Explain what makes the op-amp ideal to amplify alternating
                       voltages.                                                                   (2)

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3.5       FIGURE 3.5 below shows the circuit diagram of an inverting op amp.

                                                                   RF

                                     RIN = 1,8 kΩ              +9 V

                                                        X                                     VOUT = 8 V
            VIN = 0,4 V                                                                                         t
                                t
                                                               -9 V
                                                                                            0V

                                       FIGURE 3.5: INVERTING OP AMP
          3.5.1           Explain why point X on the diagram is also known as the virtual
                          ground.                                                                                        (2)
          3.5.2           Calculate the value of feedback resistor RF.                                                   (3)
3.6       FIGURE 3.6 below shows the internal circuit diagram of a 555 IC. Answer the
          questions that follow.
                                       + VCC                                        Control
                                       Supply    Discharge     Threshold            voltage

                                         8             7            6                 5

                                5 kΩ

                                                Comparator 1                   Q
                                                               S
                                                                        Flip
                                5 kΩ                                    Flop
                                                Comparator 2   R               Q

                                                T1
                                5 kΩ                                       Output
                                                                           Driver

                                        1              2            3                4

                                       Ground        Trigger       Output           Reset
                                                FIGURE 3.6: 555 IC
          3.6.1           State ONE industrial application where the 555 IC is used as a
                          timing device.                                                                                 (1)
          3.6.2           Indicate whether transistor T1 acts as a switch or as an amplifier in
                          the circuit.                                                                                   (1)
          3.6.3           Explain the function of the two comparators in FIGURE 3.6.                                     (4)
                                                                                                                         [30]
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QUESTION 4: SWITCHING CIRCUITS

4.1        State ONE distinct difference between the astable multivibrator and the
           bistable multivibrator with reference to their inputs.                                   (2)

4.2        Refer to FIGURE 4.2 below and answer the questions that follow.

                                                                 RF

                                                                  +12 V
                                                         A
                                                             -
                                                         B   +
                                                                  -12 V     R1
                                         C1
                                                                                     VOUT
            VC
                                                                            R2

                                            t

                                     FIGURE 4.2: MULTIVIBRATOR

           4.2.1       Identify the multivibrator in FIGURE 4.2.                                    (1)

           4.2.2       Describe the operation of the multivibrator in FIGURE 4.2 from
                       a point where the capacitor has just discharged and point A is low.          (6)

           4.2.3       Explain how the frequency of the multivibrator in FIGURE 4.2 can
                       be increased.                                                                (2)

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4.3        FIGURE 4.3 below shows a monostable multivibrator using a 555 IC.

                                          +9V

                                       R1
                                      1 kΩ                                                 R3
                                                                                          330 Ω

                      R2              VR1                                                 LED 1
                     10 kΩ           10 kΩ

                                                        8       4
                                                    7                   Output
                                                                    3
                                                    6     555
                                                    2
                                                        1       5                          R4
                     Trigger          C1                                                  330 Ω
                                                                     C2
                                     10 µF                                                LED 2
                                                                    10 nF

                               FIGURE 4.3: MONOSTABLE MULTIVIBRATOR
           4.3.1        State the function of capacitor C2.                                                    (2)
           4.3.2        FIGURE 4.3.2 below shows the trigger input, capacitor charge and
                        output signals of the multivibrator in FIGURE 4.3. The variable
                        resistor (VR1) is set to 5 kΩ. On the ANSWER SHEET for
                        QUESTION 4.3.2, draw the charging voltage VC1 and
                        corresponding output if variable resistor (VR1) is changed to 10 kΩ.

                                                                                 Trigger input
                                      ⅓ VCC
                                        0V
                                                                                    t

                                       ⅔ VCC
                                                                                  VC1 when
                                                                                 VR1 is set to
                                        0V                                          5 kΩ
                                                                                    t

                                      High
                                                                                 Output

                                       Low
                                                                                     t

                                                FIGURE 4.3.2: SIGNALS                                          (4)
           4.3.3        State whether LED 1 or LED 2 will be ON after the trigger switch is
                        pressed. Motivate your answer.                                                         (3)
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4.4        FIGURE 4.4 below shows the circuit diagram of a non-inverting Schmitt
           trigger. Answer the questions that follow.

                                                                  +9 V

                                                                                         VOUT
                                                                    -9 V
               VIN                         VIN
                                                     R1                 RF
                                       t

                         FIGURE 4.4: NON-INVERTING SCHMITT TRIGGER
           4.4.1       Indicate whether this is an open-loop mode op-amp circuit or a
                       closed-loop mode op-amp circuit. Motivate your answer.                            (2)
           4.4.2       Draw the output waveform of the Schmitt trigger on the
                       ANSWER SHEET for QUESTION 4.4.2.                                                  (4)
           4.4.3       State how the trigger voltage levels of the Schmitt trigger can be
                       adjusted without changing the supply voltage.                                     (2)
4.5        Refer to FIGURE 4.5 below and answer the questions that follow.

              V1
            0,5 V
                          t                                             RF 10 kΩ
                                           C1    R1 2 kΩ
                              R4

                                                             S1           +12 V
             V2
            0,2 V                                                   -
                         t                 C2    R2 500 Ω
                                                                    +
                              R5                                                             VOUT
                                                                          -12 V

                                     FIGURE 4.5: SUMMING AMPLIFIER
           4.5.1       State the function of capacitor C1.                                               (1)
           4.5.2       Calculate the value of the output voltage.                                        (3)
           4.5.3       Explain what makes it possible for this amplifier to amplify both
                       positive and negative voltages.                                                   (3)
           4.5.4       Explain how the output voltage will be affected if switch S 1 is open.            (2)

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4.6        Refer to FIGURE 4.6 below and answer the questions that follow.

                                                                                      +V

                                                   R1
                                                                       +V
                                             VIN

                               VIN                                                   VOUT

                   VREF                                                -V
                                                   R2
                    0V

                                      FIGURE 4.6: OP-AMP CIRCUIT

           4.6.1          Identify the op-amp circuit in FIGURE 4.6.                                    (2)

           4.6.2          Draw the output signal of the op amp on the ANSWER SHEET for
                          QUESTION 4.6.2.                                                               (4)

           4.6.3          Explain why this op-amp circuit is driven into saturation during
                          its operation.                                                                (2)

4.7        Explain the operation of the passive RC differentiator in FIGURE 4.7 below.

                                               C
                                                                            Output
                              Input
                   +9 V                                           +9 V

                                                             R         0
                     0                                                                    t
                                        t
                                                                   -9 V

                              FIGURE 4.7: PASSIVE RC DIFFERENTIATOR                                     (5)

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4.8        FIGURE 4.8 below shows an op-amp integrator with input and output signals.
           Answer the questions that follow.

                   +V                                               CF

             Input
                                                     RIN            +V
                   0V                       VIN
                                        t                       -
                   0V                                                                VOUT
                                                                +
            Output
                                                                    -V
                -VSAT                                                                 0V

                                     FIGURE 4.8: OP-AMP INTEGRATOR

           4.8.1         Explain why the op-amp integrator is able to produce a steadily
                         falling output voltage when a square wave is applied to the input.       (6)

           4.8.2         On the ANSWER SHEET for QUESTION 4.8.2, draw the output
                         waveform of the op-amp when the RC time constant is shortened
                         from the given state.                                                    (2)

           4.8.3         On the ANSWER SHEET for QUESTION 4.8.3, draw the output
                         waveform of the op-amp when the RC time constant is lengthened
                         from the given state.                                                    (2)
                                                                                                  [60]

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QUESTION 5: AMPLIFIERS

5.1       Define the following terms with reference to amplifiers:

          5.1.1        Feedback                                                                       (2)

          5.1.2        Distortion                                                                     (2)

5.2       Refer to FIGURE 5.2 below and answer the questions that follow.

                                                                                         + 9 VCC

                                      R1           RC
                                                  470 Ω                  C2
                                     10 kΩ
                                                                        10 µF

                                      C1
                                     1 µF
                                                             T1
                                                           β = 120

                                                                                           VCE
                VIN
                                                                                          2,38 V
             2 mV (AC)
                                                                 CE
                                       R2            RE        100 µF
                                     1,5 kΩ         1 kΩ

                                                                                            0V

                             FIGURE 5.2: AMPLIFIER CIRCUIT DIAGRAM

          5.2.1        Identify the amplifier in FIGURE 5.2.                                          (1)

          5.2.2        Describe the biasing method for Class A amplification.                         (4)

          5.2.3        Determine the voltage drop across RC.                                          (3)

          5.2.4        Calculate the voltage gain of the circuit in decibels.                         (3)

          5.2.5        Explain how an increase in VIN will affect the output voltage (VCE) of
                       the amplifier in FIGURE 5.2.                                                   (5)

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5.3       FIGURE 5.3 below shows the input characteristic curve of a common emitter
          amplifier. Identify A, B and C.

                                                 A

                                                               Q
                                      Base
                                     Current

                                                                              B

                                                                   C

                                 FIGURE 5.3: CHARACTERISTIC CURVE                                            (3)
5.4       Refer to FIGURE 5.4 below and answer the questions that follow.

                                                                          +VCC

                                 RB1

                            T1                                                    T2
                                                        Q1

                                                                                               Output
                                                                                               signal

                                                        Q2

                                 RB2                             RE

                                                                        0V

                             FIGURE 5.4: AMPLIFIER CIRCUIT DIAGRAM
          5.4.1        Identify the amplifier circuit in FIGURE 5.4.                                         (1)
          5.4.2        Identify the type of transistor used in the circuit.                                  (1)
          5.4.3        Explain why the circuit in FIGURE 5.4 will not consume power
                       when the input signal is zero.                                                        (3)
          5.4.4        Discuss the principle of operation of the amplifier in FIGURE 5.4.                    (5)

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5.5       Refer to the LC resonant circuit of a radio-frequency amplifier and its input
          characteristics in FIGURE 5.5 below and answer the questions that follow.

                                                     + Vcc

                                                       C2
                              C1        L1   L2              Output
                                                                                IC (mA)

                                                                                                               IB (µA)
                     C                                              Collector
                                                                    Current
                                   T1
                                                             Δ IC

                                                                                                                VCE
             Audio
             input          RE                CE                                                                Q
                                                                        θC < 180°

                                                                                                     Δ VCE
                                                    0V
                                                                                          Output voltage

              FIGURE 5.5: LC RESONANT CIRCUIT AND INPUT CHARACTERISTICS

          5.5.1           Name the class of amplification used by the circuit in FIGURE 5.5.                              (1)

          5.5.2           Describe a radio-frequency amplifier.                                                           (3)

          5.5.3           Indicate how the resonating frequency of the circuit in FIGURE 5.5
                          can be varied.                                                                                  (1)

          5.5.4           Name the filter which blocks all frequencies, except those between
                          certain limits.                                                                                 (1)

          5.5.5           Explain energy transfer in the tank circuit which allows the
                          RF amplifier to execute its function.                                                           (3)

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5.6       Refer to FIGURE 5.6 below and answer the questions that follow.

                                                                                    + Vcc

                                                                   L3
                                             R1

                                          C1
                                                                        COUT

                                          C2

                                                                   Q1
                       L1

         C3                                                                                 VOUT

                       L2
                                            R2                RE
                                                                           CE

                                                                                              0V

                            FIGURE 5.6: OSCILLATOR CIRCUIT DIAGRAM

          5.6.1        Identify the oscillator in FIGURE 5.6.                                       (1)

          5.6.2        Discuss how oscillation is achieved in this circuit.                         (6)

          5.6.3        Describe how feedback is obtained in the circuit.                            (4)

          5.6.4        Explain the function of inductor L3.                                         (3)

5.7       Explain why a field-effect transistor (FET) is preferred over a bipolar junction
          transistor (BJT) in oscillator circuits.                                                  (2)

5.8       State TWO similarities between the Colpitts oscillator and the Hartley
          oscillator.                                                                               (2)
                                                                                                    [60]

                                                                                      TOTAL:        200

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                                                       FORMULA SHEET
RLC CIRCUITS                                             SEMICONDUCTOR DEVICES
P  V  I  cos θ                                                  V       R 
                                                         Gain A V  OUT   F 
XL  2 fL                                                          VIN     RIN 
          1                                                             R 
XC                                                      VOUT  VIN    F 
        2 fC                                                           R IN 
            1                f f
fr                  OR fr  2 1                                          R 
   2 LC                       2                         VOUT  VIN  1  F 
     f                                                                    R IN 
BW  r   OR               BW  f2  f1
     Q                                                   SWITCHING CIRCUITS
Series                                                              R        R         R 
                                                         VOUT    V1 F  V2 F  ...VN F 
VR  I R                                                            R1       R2        RN 
VL  I XL                                                                 VOUT         VOUT
                                                         Gain A V             
VC  I XC                                                                  VIN   V1  V2  ...VN 
       VT                                                VOUT   (V1  V2  ...VN )
IT                 OR        IT  IR  IC  IL
       Z                                                 AMPLIFIERS
                                                                VC
Z  R 2  X L  X C                                    IC 
                              2
                                                                RC
VT  VR  VL  VC 
                2                 2
                                      OR    VT  I Z     VCC  VCE  ICRC
            R                              VR
Cos θ               OR       Cos θ                     VB  VBE  VRE
            Z                              VT

       XL XC VL VC 1 L                                           VOUT
Q                                                   AV 
       R   R VT VT R C                                            VIN
Parallel                                                       I
                                                         A I  OUT
VT  VR  VL  VC                                                IIN
                                                               P
IR 
    VT                                                   A P  OUT                        A P  A V  AI
     R                                                           PIN              OR
    V
IC  T                                                   A = β1 x β 2             OR       A V  A V1  A V2  A V3
    XC
       VT
IL                                                      PIN  I2  ZIN                    POUT  I2  Z OUT
       XL                                                                         AND

IT  IR  IL  IC 
            2             2
                                                         GAIN IN DECIBELS
       VT                                                              I
Z                                                       A I  20log10 OUT
       IT                                                                IIN
       I                                                                V
Cos θ  R                                                A V  20log10 OUT
       IT                                                                 VIN
       XL XC IL IC 1 L                                                     POUT
Q                                                   A P  10log10
       R   R IT IT R C                                                      PIN

Copyright reserved

### Page 20

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Electrical Technology: Electronics                  DBE/November 2020
                                     SC/NSC

CENTRE NUMBER:

EXAMINATION NUMBER:

ANSWER SHEET

QUESTION 2: RLC CIRCUITS

2.1.1

                                     VR = 20 V

                                                    Transfer mark to
                                                      answer book

                                                              MOD
                                     FIGURE 2.1.1                       (2)

2.2.4

                                                     Transfer mark to
                                                       answer book

                                                               MOD
                                     FIGURE 2.2.4                       (5)

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### Page 21

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Electrical Technology: Electronics                            DBE/November 2020
                                     SC/NSC

CENTRE NUMBER:

EXAMINATION NUMBER:

ANSWER SHEET

QUESTION 4: SWITCHING CIRCUITS

4.3.2

                                              Trigger input
             ⅓ VCC
                0V
                                                 t

              ⅔ VCC
                                               VC1 when
                                              VR1 is set to
                                                 5 kΩ
                                                 t

              High
                                              Output

              Low
                                                 t

              ⅔ VCC
                                               VC1 when
                                              VR1 is set to
                                                10 kΩ
                                                 t

              High
                                                               Transfer mark to
                                              Output when        answer book
                                              VR1 is set to
                                                 10 kΩ
              Low
                                                 t
                                                                         MOD
                                     FIGURE 4.3.2                                 (4)

Copyright reserved

### Page 22

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Electrical Technology: Electronics                                      DBE/November 2020
                                     SC/NSC

CENTRE NUMBER:

EXAMINATION NUMBER:

ANSWER SHEET

4.4.2
              VIN
                                                        Upper
                                                        trigger level

               0
                                                    t

                                                        Lower
                                                        trigger level

              +V

               0
                                                    t

                                                                         Transfer mark to
                                                                           answer book

              -V

                                                                                   MOD
                                     FIGURE 4.4.2                                           (4)

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### Page 23

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Electrical Technology: Electronics                  DBE/November 2020
                                     SC/NSC

CENTRE NUMBER:

EXAMINATION NUMBER:

ANSWER SHEET

4.6.2                       VIN

              VREF

               0V

            +VSAT

              0V
                                          t
                                                     Transfer mark to
                                                       answer book

             -VSAT
                                                               MOD
                                     FIGURE 4.6.2                       (4)

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### Page 24

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Electrical Technology: Electronics                              DBE/November 2020
                                     SC/NSC

CENTRE NUMBER:

EXAMINATION NUMBER:

ANSWER SHEET

4.8.2            +V

               Input

                 0V
                                      t
                 0V
                                          RC time constant is
                                                                 Transfer mark to
                                                shorter            answer book
             Output

                -VSAT                                                      MOD
                                     FIGURE 4.8.2                                   (2)

4.8.3             +V

               Input

                 0V
                                      t
                 0V
                                          RC time constant is
                                                                 Transfer mark to
                                                longer             answer book
              Output

                 -VSAT                                                     MOD
                                     FIGURE 4.8.3                                   (2)

Copyright reserved

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