Refer to FIGURE 2.2 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2019 - Paper 1
Question 2
Refer to FIGURE 2.2 below and answer the questions that follow.
### 2.2.1 State the function of R1 and R2.
### 2.2.2 Describe what happens when the set switch, S1,... show full transcript
Worked Solution & Example Answer:Refer to FIGURE 2.2 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2019 - Paper 1
Step 1
State the function of R1 and R2.
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Answer
R1 and R2 are pull-up resistors used in the bistable multivibrator circuit. They hold the threshold and trigger pins at a specific voltage level when there is no input signal, ensuring stable operation of the circuit by preventing unintended triggering.
Step 2
Describe what happens when the set switch, S1, is pressed.
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Answer
When the set switch, S1, is pressed, it pulls the trigger pin (pin 2) low, causing the output state of the 555 timer to toggle. This results in the LED turning on, as the output pin (pin 3) goes high and activates the LED circuit.
Step 3
Explain why threshold pin 6 is connected directly to ground.
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Answer
Threshold pin 6 is connected directly to ground to set a reference level for the 555 timer. This allows the circuit to reset and ensures that it can respond correctly to changes in the input, allowing the multivibrator to function properly by detecting the voltage drop when S1 is pressed.