Objective
The objective of this experiment is to evaluate the effectiveness of axial capacitors in power filtering applications. This experiment aims to observe how axial capacitors can smoothen voltage fluctuations in a power supply circuit.
Materials Needed
- Axial capacitors of various values (e.g., 10µF, 100µF, 220µF)
- Power supply (DC source)
- Oscilloscope
- Multimeter
- Breadboard or PCB for assembly
- Resistors (e.g., 1kΩ)
- Jumper wires
- Safety equipment (gloves, goggles, etc.)
Theory
Axial capacitors are widely used in power supply circuits to filter out AC noise and voltage fluctuations. They store charge and release it when the supply voltage dips, effectively smoothing out the voltage levels. The effectiveness of a capacitor in filtering can be analyzed through the impedance it presents at different frequencies, calculated as:
Z = 1 / (2 * π * f * C)
Where **Z** is the impedance, **f** is the frequency, and **C** is the capacitance value. The larger the capacitance, the lower the impedance at a given frequency, making it more effective at filtering.
Steps
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Set Up the Circuit
Assemble the power filtering circuit on a breadboard or PCB. Connect the axial capacitor in parallel with a load resistor to form the filtering network. A simple circuit diagram should be referenced for proper connections.
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Connect the Power Supply
Connect the power supply to the circuit. Ensure the voltage is set to a level that is appropriate for the components used, typically around 5V to 12V for this experiment.
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Measure Input Voltage
Use the multimeter to measure and record the input voltage across the power supply.
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Observe Output Voltage
Connect the oscilloscope probes to the output across the load resistor and observe the waveform. Record the output voltage and note any fluctuations.
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Change Capacitor Values
Replace the axial capacitor with capacitors of different values (e.g., 10µF, 100µF, 220µF) one at a time. Repeat the measurements for each capacitor value, observing and recording the effect on the output voltage waveform.
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Analyze Results
Compare the waveforms for different capacitor values. Analyze how each capacitor value affected the smoothing of voltage fluctuations.
Data and Calculations
Record the measured input and output voltages in the table below:
| Capacitance (µF) | Input Voltage (V) | Output Voltage (V) |
|---|---|---|
| 10 | 5.0 | 4.5 |
| 100 | 5.0 | 4.8 |
| 220 | 5.0 | 4.9 |
Conclusion
This experiment demonstrates the effectiveness of axial capacitors in power filtering applications. The observed improvement in output voltage stability with increased capacitance highlights the role of capacitors in mitigating voltage fluctuations and ensuring a smoother power supply for electronic circuits.