Lab: Half and Full Wave Rectified Sine Waves
In this lab you will construct and measure the output of a half wave and a full wave rectifier and the filtered output. In addition you will learn to use the Math function on the oscilloscope.
Equipment
1. Function Generator (FG)
2. Oscilloscope
Materials
1. (4) 1N4002 Diodes
2. 1k Ohm Resistor
3. 10uF and 100uF Capacitor
Procedure
Figure 2- 1
1. Assemble the circuit shown above. Set the FG to provide V1 to the circuit
2. Once assembled, measure V1 with channel 1 of the oscilloscope and the voltage across the resistor with channel 2. Measure and record the maximum and minimum voltages of the rectified waveform. Save a screenshot (image of waveforms) including measured values.
3. Shut off the FG, add a 10uF capacitor (filter) in parallel with the load. Measure and record the peak-to-peak voltage of the ripple voltage. Save a screenshot including measured values.
4. Replace the 10uF capacitor with the 100uF capacitor and repeat step 3. Save a screenshot.
5. Calculate the ripple factor for each filter.
6. Do not turn on power until instructed to. Now, assemble the circuit in Figure 2-2. Connect the grounds of the function generator and both scope probes to an earth ground which is available as a metal post on the oscilloscope. Use channel 1 to measure the voltage on node 3 and use channel 2 to measure the voltage on node 1. Ask the lab instructor to verify the circuit and probes before applying power to it. Once the circuit is approved, apply power from the FG. Use the math function on the oscilloscope to subtract channel 1 from channel 2 to get the output waveform as seen by the resistor. Measure and record the maximum and minimum voltages of the rectified (Math) waveform. Save a screenshot including measured values.
7. Add the 10uF capacitor to the circuit across R1 again. Note how the shape of the wave looks and measure and record the peak-to-peak voltage of the ripple voltage. Save a screenshot including measured values.
8. Replace the 10uf capacitor with the 100uF capacitor and repeat step 7. Save a screenshot.
9. Calculate the ripple factor for each filter.
BONUS: Remove the load (and the filter(s)) from the circuit and repeat step 6. What happened to the rectified voltage waveform and why?
Submittal:
Data section will include two circuits, six screenshots including measured values, four ripple factor calculations. (Nothing submitted should be hand-written)
DISCUSSION- Include discussion about the shapes of the waveforms for each variation of the circuit that was mentioned in the lab with respect to the corresponding theoretical material discussed in lecture. Discuss what the circuit does and also discuss the importance of the capacitor.
Include observations and explanations in paragraph form, regarding BONUS section instructions above.