Objective

The goal of this experiment is to demonstrate how a trimmer resistor can be used to fine-tune a circuit. We will observe how adjusting the resistance of the trimmer changes the output voltage in a simple voltage divider circuit.

Components Required

• 1 x Trimmer Resistor (10kΩ)
• 2 x Fixed Resistors (1kΩ)
• 1 x DC Power Supply (5V)
• 1 x Multimeter
• 1 x Breadboard
• Connecting Wires

Theory

A trimmer resistor is a type of variable resistor used to make precise adjustments in circuits. In this experiment, we will use the trimmer in a voltage divider circuit. By adjusting the resistance, we can fine-tune the output voltage, which is useful in applications such as sensor calibration or tuning oscillators.

Circuit Diagram

Experimental Setup

1. Connect the 5V DC power supply to the breadboard's power rail.

2. Place one 1kΩ fixed resistor from the power rail to one side of the trimmer resistor.

3. Connect the wiper (middle pin) of the trimmer resistor to the output voltage node, which will connect to the multimeter.

4. Place the other 1kΩ fixed resistor between the wiper and ground.

5. Use the multimeter to measure the output voltage at the wiper of the trimmer resistor.

Procedure

1. Turn on the power supply and set it to 5V.
2. Measure the voltage across the output node using the multimeter.
3. Adjust the trimmer resistor slowly using a small screwdriver.
4. Observe how the output voltage changes as you turn the screw on the trimmer resistor.
5. Record the different voltage readings as you adjust the trimmer.
6. Turn the trimmer in both directions to explore the full range of voltage adjustment.

Results and Observations

You should observe that as you adjust the trimmer resistor, the output voltage will vary smoothly between its maximum and minimum values. The range of adjustment depends on the values of the fixed resistors and the trimmer resistor.

Conclusion

This experiment demonstrates how a trimmer resistor can be used to fine-tune a circuit. In a voltage divider configuration, adjusting the trimmer allows for precise control over the output voltage, which is useful for calibration and signal adjustments in many electronic circuits.