Electrical Technology Grade 12 NSC November 2023 QP (Eng)

Downloaded from hlayiso.com GRAAD 12 NATIONAL SENIOR CERTIFICATE GRADE 12 ELECTRICAL TECHNOLOGY: ELECTRONICS NOVEMBER 2023 MARKS: 200 TIME: 3 hours This question paper consists of 25 pages, a 1-page formula sheet and a 6-page answer sheet. Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 2 DBE/November 2023 NSC INSTRUCTIONS AND INFORMATION 1. This question paper consists of SIX questions. 2. Answer ALL the questions. 3. Answer the following questions on the attached ANSWER SHEETS: QUESTIONS 5.2.5, 5.4.3, 5.5.3 and 5.7 QUESTIONS 6.4.3, 6.5.2 and 6.7.3 4. Write your centre number and examination number on every ANSWER SHEET and hand them in with your ANSWER BOOK, whether you have 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. Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 3 DBE/November 2023 NSC QUESTION 1: MULTIPLE-CHOICE QUESTIONS Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.15) in the ANSWER BOOK, e.g. 1.16 D. 1.1 The following can be considered as dangerous practices: A The use (or misuse) of power tools B The incorrect use and handling of hand tools C The etching of printed circuit boards D All the above-mentioned (1) 1.2 … is the reference quantity in a parallel RLC circuit. A Current B Resistance C Reactance D Voltage (1) 1.3 The reactance of a … must be equal for a circuit to resonate. A resistor and an inductor B resistor and a capacitor C capacitor and an inductor D transducer and a capacitor (1) 1.4 The following condition is common to both series and parallel resonance: A The impedance is minimum. B The current is maximum. C The bandwidth is affected by its quality factor. D The Q-factor depends on voltage amplification. (1) 1.5 ONE of the advantages of the field-effect transistor is its extremely … A low input resistance. B low input and output resistance. C high output resistance. D high input resistance. (1) 1.6 The ratio of the internal resistances of a UJT is called … A negative resistance ratio. B common-mode rejection ratio. C intrinsic standoff ratio. D extrinsic standoff ratio. (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 4 DBE/November 2023 NSC 1.7 A … circuit is used to eliminate switch bounce in switching circuits. A comparator B bistable multivibrator C monostable multivibrator D differentiator (1) 1.8 When negative feedback is used in an op amp, the bandwidth … A increases. B decreases. C is equal to zero. D stays the same. (1) 1.9 The … is a switching circuit with two inputs that is able to store one bit of data at a time. A bistable multivibrator B monostable multivibrator C astable multivibrator D passive integrator (1) 1.10 An op-amp application that uses positive feedback is the … A comparator. B summing amplifier. C Schmitt trigger. D differentiator. (1) 1.11 The op-amp comparator is an extremely sensitive circuit because … A it is the only op-amp application that uses closed loop gain. B there is no feedback connection between the output and the input. C it makes use of the virtual ground concept. D the supply voltage is connected to it. (1) 1.12 ONE of the key operating principles in an op-amp integrator circuit: A When a constant current is fed to the capacitor, it will charge at a constant fixed rate rather than exponentially. B The two input terminals of the op amp have different voltages at all times. C The inputs of the op amp draw maximum current so that any input current is blocked by the feedback circuit. D The current fed to the capacitor causes it to charge exponentially. (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 5 DBE/November 2023 NSC 1.13 The efficiency of a class C amplifier is … A less than the efficiency of a class A amplifier. B less than the efficiency of a class B amplifier. C less than the efficiency of a class AB amplifier. D greater than the efficiency of a class A, B or AB amplifier. (1) 1.14 A bipolar junction class B push-pull amplifier with no transformer coupling uses … A two NPN transistors. B two PNP transistors. C complementary transistors. D none of the above-mentioned. (1) 1.15 A/An ... is a circuit that produces an output waveform without an internal signal source. A bistable multivibrator B amplifier C Schmitt trigger D oscillator (1) [15] QUESTION 2: OCCUPATIONAL HEALTH AND SAFETY 2.1 Name TWO incidents arising out of activities of people at the workplace that must be reported to the health and safety inspector. (2) 2.2 Define the term danger with reference to the Occupational Health and Safety Act, 1993 (Act 85 of 1993). (2) 2.3 Explain why the location of the emergency master switch is important for safety in and around the workshop. (2) 2.4 State TWO effects a third-degree burn has on a person's body. (2) 2.5 Name TWO first-aid steps to take after a person has been shocked by an electric current. (2) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 6 DBE/November 2023 NSC QUESTION 3: RLC CIRCUITS 3.1 State the relationship between inductive reactance and frequency. (1) 3.2 Refer to FIGURE 3.2 below and state the phase relationship between the current and voltage waveforms. +V V I 0 90º 180º 270º 360º t -V FIGURE 3.2: CURRENT AND VOLTAGE WAVEFORMS (1) 3.3 FIGURE 3.3 below shows an RLC series circuit which consists of a resistor with a resistance of 6 Ω, an inductor with an inductance of 0,02 H and a capacitor with a capacitance of 80 µF which are all connected across an alternating supply of 100 V/100 Hz. L = 0,02 H C = 80 µF R=6Ω VR = 63,42 V VL = 132,86 V VC = 210,24 V IT = 10,57 A VT = 100 V/100 Hz FIGURE 3.3: RLC SERIES CIRCUIT Given: R = 6Ω L = 0,02 H C = 80 µF VR = 63,42 V VC = 210,24 V VL = 132,86 V VT = 100 V IT = 10,57 A f = 100 Hz Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 7 DBE/November 2023 NSC 3.3.1 State whether the supply current is leading or lagging the supply voltage. Motivate your answer. (2) 3.3.2 Redraw and complete the phasor diagram of the circuit diagram in FIGURE 3.3 in the ANSWER BOOK. VL = 132,86 V IT = 10,57 A VR = 63,42 V VC = 210,24 V FIGURE 3.3.2: PHASOR DIAGRAM (4) 3.3.3 Prove that the resultant of VR, VL and VC equals the supply voltage. (3) 3.3.4 Calculate the frequency at which the circuit will resonate. (3) 3.4 Refer to FIGURE 3.4 below and answer the questions that follow. 3A R C 5A L 5A IT VT FIGURE 3.4: CIRCUIT DIAGRAM 3.4.1 Calculate the total current of the circuit. (3) 3.4.2 Calculate the phase angle. (3) 3.4.3 Draw a fully labelled phasor diagram for the circuit in FIGURE 3.4 above in the ANSWER BOOK. (4) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 8 DBE/November 2023 NSC 3.5 A series circuit consists of a resistor with a resistance of 30 ohms, an inductor with an inductance of 10 mH and a capacitor with a capacitive reactance of 300 ohms. This combination is connected across an alternating supply of 30 V and resonates at a frequency of 4,77 kHz. L = 10 mH R = 30 Ω XC = 300 Ω VR VC VL IT = 1 A 30 V/fr = 4,77 kHz FIGURE 3.5: RESONANCE RLC SERIES CIRCUIT Given: R = 30 Ω Xc = 300 Ω L = 10 mH VT = 30 V fr = 4,77 kHz IT = 1A 3.5.1 Calculate the Q-factor of the circuit. (3) 3.5.2 Calculate the bandwidth of the circuit. (3) 3.5.3 Calculate the voltage drop across the inductor. (3) 3.5.4 Explain why the voltage across the inductor is greater than the value of the supply voltage. (2) [35] Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 9 DBE/November 2023 NSC QUESTION 4: SEMICONDUCTOR DEVICES 4.1 Refer to FIGURE 4.1 below of the construction of a JFET and answer the questions that follow. A Gate B C D FIGURE 4.1: CONSTRUCTION OF A JFET 4.1.1 Label A and B. (2) 4.1.2 Briefly describe the construction of the junction field-effect transistor (JFET). (2) 4.1.3 Describe how the flow of current is restricted in the JFET when the value of the VGS is increased. (3) 4.2 Refer to FIGURE 4.2 of a characteristic curve below and answer the questions that follow. ID (mA) VGS = +1,5 V 16 VGS = +1 V 12 A VGS = +0,5 V 8 VGS = 0 V 6 VGS = -1 V 4 VGS = -2 V B 2 VGS = -3 V 0 VDS 5V 10 V 15 V FIGURE 4.2: CHARACTERISTIC CURVE Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 10 DBE/November 2023 NSC 4.2.1 Identify the characteristic curve in FIGURE 4.2. (1) 4.2.2 Label A and B. (2) 4.3 Refer to MOSFETs and answer the questions that follow. 4.3.1 Name TWO electronic devices that use metal-oxide-semiconductor field-effect transistors (MOSFETs). (2) 4.3.2 Briefly describe, with reference to the gate, how the MOSFET differs from the JFET. (2) 4.4 FIGURE 4.4 below shows a UJT speed-control circuit diagram. Answer the questions that follow. SCR A C G R1 R2 E B2 D1 M B1 C R3 FIGURE 4.4: UJT SPEED-CONTROL CIRCUIT DIAGRAM 4.4.1 Explain how the value of R1 affects the rate at which the capacitor will charge. (2) 4.4.2 Discuss how the UJT, together with the SCR, control the speed of the motor in FIGURE 4.4. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 11 DBE/November 2023 NSC 4.5 Refer to FIGURE 4.5 below and answer the questions that follow. VCC = 9 V R1 RC VRC = 8 V C IB B Q1 C1 Q2 E Output Input R2 RE VRE = 0,1 V CE 0V FIGURE 4.5: DARLINGTON CIRCUIT 4.5.1 State TWO advantages of a Darlington transistor pair. (2) 4.5.2 Refer to the circuit and determine the collector emitter voltage in the circuit. (1) 4.5.3 Explain how the input base current receives double amplification in a Darlington transistor. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 12 DBE/November 2023 NSC 4.6 Refer to FIGURE 4.6 below of an inverting operational amplifier and answer the questions that follow. RF = 1,2 kΩ RIN =1 k Ω +15 V _ VOUT VIN =60 mV + -15 V 0V FIGURE 4.6: INVERTING OPERATIONAL AMPLIFIER 4.6.1 State the purpose of the feedback resistor (RF). (1) 4.6.2 Explain why op amps are seldom used in open-loop mode. (2) 4.6.3 Calculate the voltage gain of the circuit. (3) 4.7 Refer to FIGURE 4.7 below and answer the questions that follow. C1 10 µF C2 +9 V 22 µF V IN V OUT RF RB -9 V 120 k 10 k R1 10 k FIGURE 4.7: NON-INVERTING OP AMP 4.7.1 State TWO functions of resistor RB in FIGURE 4.7. (2) 4.7.2 Calculate the voltage gain of the circuit in FIGURE 4.7. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 13 DBE/November 2023 NSC 4.8 Refer to FIGURE 4.8 below and answer the questions that follow. +Vcc Ground 1 8 Supply 5k Ω 5k Ω 5k Ω T Trigger 2 7 Discharge + _ + _ 2 1 R S Output 3 6 Threshold Flip- flop Output Q driver Control Reset 4 5 voltage FIGURE 4.8: 555 IC PIN LAYOUT 4.8.1 Name TWO applications of the 555 IC. (2) 4.8.2 State TWO disadvantages of the 555 IC. (2) 4.8.3 Describe the function of pin 4. (3) 4.8.4 State the functions of the following components in FIGURE 4.8 above: (a) NPN transistor (1) (b) Comparator 2 (1) [45] Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 14 DBE/November 2023 NSC QUESTION 5: SWITCHING CIRCUITS 5.1 Differentiate between bistable multivibrators and astable multivibrators with reference to the output states. (2) 5.2 FIGURE 5.2 below shows the circuit of an op amp as a bi-stable multivibrator. Answer the questions that follow. +9 V S1 C1 = 10 µF 2 7 R3 6 741 1 kΩ 4 R2 3 1 kΩ R5 1 kΩ V R4 680 Ω S2 R1 470 Ω -9V FIGURE 5.2: BISTABLE MULTIVIBRATOR 5.2.1 Explain the function of R1 and R2. (2) 5.2.2 State the polarity of the output when S2 is pressed. (1) 5.2.3 Explain the operation of the circuit when S1 is pressed. (1) 5.2.4 Deduce the value of the output voltage when S1 is pressed. (3) 5.2.5 Refer to the input in FIGURE 5.2.5 below and draw the output waveform on the ANSWER SHEET for QUESTION 5.2.5. Input 0V t FIGURE 5.2.5: INPUT PULSES (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 15 DBE/November 2023 NSC 5.3 Refer to FIGURE 5.3 below and answer the questions that follow. +6V R2 R1 100 kΩ 33 kΩ 8 4 7 Output 6 555 3 2 1 5 R3 Trigger 470 Ω C1 220 µF FIGURE 5.3: MONOSTABLE MULTIVIBRATOR 5.3.1 State whether this circuit uses an active high trigger or an active low trigger to set the output. (1) 5.3.2 Determine the threshold voltage of the circuit. (1) 5.3.3 Explain the operation of the circuit when the trigger is pressed. (5) 5.3.4 State how you would eliminate any unwanted noise from the supply that might affect the timing of the circuit. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 16 DBE/November 2023 NSC 5.4 Refer to FIGURE 5.4 below and answer the questions that follow. +9V R1 10 k 8 4 7 R3 R2 1k 555 1k 3 2 6 1 5 LED C1 C2 10 µF 10 nF FIGURE 5.4: ASTABLE MULTIVIBRATOR 5.4.1 Explain the term duty cycle with reference to multivibrator outputs. (2) 5.4.2 State whether the charging time of the capacitor or the discharging time of the capacitor is longer. Motivate your answer. (3) 5.4.3 Draw the voltage waveform that appears across capacitor C 1 for ONE full cycle on the ANSWER SHEET for QUESTION 5.4.3. (4) 5.5 FIGURE 5.5 below shows the circuit of an inverting Schmitt trigger. +9 V VOUT 5V R1 -9 V 6,8 kΩ R2 5 kΩ FIGURE 5.5: INVERTING SCHMITT TRIGGER 5.5.1 State the advantage of making R2 variable. (1) 5.5.2 Calculate the value of the trigger voltage if R2 is set to 2,2 kΩ. (3) 5.5.3 Draw ONE cycle of the input and output waveforms for the circuit on the ANSWER SHEET for QUESTION 5.5.3 when R2 is set to 2,2 kΩ and the input waveform is sinusoidal. (6) 5.5.4 State how the value of the trigger voltage can be decreased. (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 17 DBE/November 2023 NSC 5.6 Refer to FIGURE 5.6 below and answer the questions that follow. 0,5 V V1 C1 R1 5 kΩ RF 10 kΩ t C2 R2 5 kΩ +12 V 0,2 V V2 - t C3 R3 5 kΩ VOUT + 0,3 V V3 -12 V t FIGURE 5.6: INVERTING SUMMING AMPLIFIER 5.6.1 State the purpose of the capacitors in series with the input resistors. (1) 5.6.2 Explain the advantage of using variable resistors instead of fixed- value resistors on the input of the amplifier. (2) 5.6.3 Calculate the output of the amplifier if all input resistors are set to 2 kΩ. (3) 5.7 FIGURE 5.7 below shows the op amp as differentiator with its input signal. Draw the output waveform on the ANSWER SHEET for QUESTION 5.7. RF CIN +V +V VIN - VOUT 0 + t -V -V 0V FIGURE 5.7: OP AMP AS DIFFERENTIATOR (3) [50] Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 18 DBE/November 2023 NSC QUESTION 6: AMPLIFIERS 6.1 Describe the term positive feedback with reference to oscillators. (2) 6.2 Compare a basic class A amplifier to a class B push-pull amplifier with reference to their sound reproduction. (2) 6.3 Refer to FIGURE 6.3 below and answer the questions that follow. IC (mA) +Vcc A 12 V 6 5 R L =2 kΩ RB 4 C 3 Q1 2 β=100 1 VBE D B VCE 0V 2 4 6 8 10 12 X Y FIGURE 6.3: DC LOAD AND TRANSISTOR BIASING 6.3.1 Determine the value of VRL in FIGURE 6.3 Y above when the transistor is ON. (1) 6.3.2 If the load line in FIGURE 6.3 X above is changed to CD, describe what changes were made to the circuit to effect this. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 19 DBE/November 2023 NSC 6.4 Refer to FIGURE 6.4 below and answer the questions that follow. IC (mA) 12 Input signal 10 K I B5 8 Saturation 6 I B4 L I B3 4 IB2 2 M I B1 Output waveform Cut- off region 0 2 4 6 8 10 12 N VCE FIGURE 6.4: TRANSISTOR OUTPUT CHARACTERISTIC CURVE 6.4.1 Identify the region between K and M on the characteristic curve. (1) 6.4.2 Name ONE factor that influences the bias stability in a transistor amplifier. (1) 6.4.3 Draw the output waveform and input signal on the ANSWER SHEET for QUESTION 6.4.3 (NOT to scale) when the circuit in FIGURE 6.4 above is biased in class B. (4) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 20 DBE/November 2023 NSC 6.5 Refer to FIGURE 6.5 below and answer the questions that follow. +VCC = 12V R1 RC C 2 =10 µF IC = 10 mA C1 = 10 µF VBE = 0,7 V VCE = 6 V β = 250 VOUT + _ R2 RE CE Input signal FIGURE 6.5: RC-COUPLED AMPLIFIER 6.5.1 Discuss the operation of the circuit in the negative half-cycle of the input signal. (3) 6.5.2 Draw, on the ANSWER SHEET for QUESTION 6.5.2, a full cycle of the output waveform when the transistor is driven into saturation. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 21 DBE/November 2023 NSC 6.6 Refer to FIGURE 6.6 below and answer the questions that follow. T1 T2 R1 Transformer R3 Transformer Q1 Q2 C2 C3 R2 RE1 C1 R4 R E2 FIGURE 6.6: TWO-STAGE TRANSFORMER-COUPLED AMPLIFIER 6.6.1 State the function of transformer (T2) in FIGURE 6.6 above. (1) 6.6.2 Explain why transformer-coupled amplifiers are more efficient than RC coupled amplifiers. (2) 6.6.3 Describe how the output impedance of the first stage can be matched to the input impedance of the second stage. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 22 DBE/November 2023 NSC 6.7 Refer to FIGURE 6.7 below and answer the questions that follow. R1 T1 R2 C R3 T2 R4 Speaker Input waveform FIGURE 6.7: COMPLEMENTARY PUSH-PULL AMPLIFIER CIRCUIT 6.7.1 Name the class of amplification used in FIGURE 6.7 above. (1) 6.7.2 Explain how the circuit in FIGURE 6.7 above overcomes the problem of cross-over distortion. (2) 6.7.3 Draw the output waveform on the ANSWER SHEET for QUESTION 6.7.3. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 23 DBE/November 2023 NSC 6.8 Refer to FIGURE 6.8 below and answer the questions that follow: +V CC L C1 T1 RE CE FIGURE 6.8: LC-RESONANT CIRCUIT 6.8.1 Identify the function of CE in FIGURE 6.8 above. (1) 6.8.2 Describe the basic function of the LC tank circuit in FIGURE 6.8 above. (3) 6.8.3 Explain the purpose of the radio frequency amplifier when used in radio circuits. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 24 DBE/November 2023 NSC 6.9 Refer to FIGURE 6.9 below and answer the questions that follow. + V CC RF choke C2 C4 R1 Output C3 Q1 L1 R2 R3 C5 C1 0V L2 FIGURE 6.9: HARTLEY OSCILLATOR 6.9.1 Identify the function of C2 and C3. (1) 6.9.2 Name TWO factors that can influence the stability of the frequency of oscillations. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Electrical Technology: Electronics 25 DBE/November 2023 NSC 6.10 Refer to FIGURE 6.10 below and answer the questions that follow. +VCC RB RC C5 VOUT C1 C2 C3 Q1 R1 R2 R3 R4 C4 0V FIGURE 6.10: RC PHASE-SHIFT OSCILLATOR 6.10.1 Explain what determines the phase difference between the current and the applied voltage in the circuit diagram. (2) 6.10.2 Explain how the circuit achieves sufficient current gain to initiate its oscillation. (2) 6.10.3 State the application of the RC phase-shift oscillator. (1) [45] TOTAL: 200 Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC FORMULA SHEET RLC CIRCUITS SEMICONDUCTOR DEVICES XC  1 VOUT  RF  2 π fC Gain A V      VIN  R IN   R  XL  2 fL VOUT  VIN    F   RIN  1  R  fr  VOUT  VIN  1  F  2 LC  R IN  SERIES SWITCHING CIRCUITS V IT  T V UT (V V V ) Z 2 3 VL  I XL VOUT   (V1  V2  V3  ....VN ) VC  I X C 2 V V AT VT  I Z 2 XL X V V 1 L Q  C  L  C  T , C Z Z VT VT R C Z  R2  XL  XC  2 T VT   VL  VC  2 2 2 VR VT V UT 2 R Cos θ  AMPLIFIERS Z VR V Cos θ  Ic  C AND VCC  VCE  ICR C VT R C I PARALLEL A  20log o i I i I Vo Cos θ  R A V  20log IT V i IT  IR 2  IL  IC 2 PO  I2  Z o IR  VR P R A P  10log o P i VC A v dB   20logA IC  V XC V VOUT  RF  IL  L Gain A V      XL VIN  RIN  C √ √ f BW  r Q √ Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET QUESTION 5: SWITCHING CIRCUITS 5.2.5 Input 0V t +VSAT Output 0V Transfer mark to t answer book - VSAT MOD FIGURE 5.2.5 (3) 5.4.3 VC ⅔ VCC ⅓ VCC Transfer mark to answer book T MOD FIGURE 5.4.3 (4) Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET 5.5.3 (V) 9 VOUT 6 + VIN 3 Upper trigger 0 (t) Lower trigger -3 - VIN -6 Transfer mark to answer book -9 MOD FIGURE 5.5.3 (6) Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET 5.7 +V 0 -V +V 0 Transfer mark to answer book -V MOD FIGURE 5.7 (3) Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET QUESTION 6: AMPLIFIERS 6.4.3 IC (mA) 12 Input signal 10 K I B5 8 Saturation 6 I B4 L I B3 4 IB2 2 M I B1 Output waveform Cut-off region 0 2 4 6 8 10 12 N VCE Transfer mark to answer book MOD FIGURE 6.4.3 (4) Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET 6.5.2 +V Input 0 t -V +V Output 0 t Transfer mark to answer book -V MOD FIGURE 6.5.2 (3) Copyright reserved

Downloaded from hlayiso.com Electrical Technology: Electronics DBE/November 2023 NSC CENTRE NUMBER: EXAMINATION NUMBER: ANSWER SHEET 6.7.3 +V 0 Input -V +V 0 Output Transfer mark to answer book -V MOD FIGURE 6.7.3 (3) Copyright reserved