Unit 1 Lab 2 Worksheet Part I: In this section, familiarize yourself with the operation of the oscilloscope in Multisim and main functions of the scope in circuit measurements. You may want to refer to Multisim help for a detailed explanation of the oscilloscope functions. (You can use any of the oscilloscopes provided in Multisim, but the generic two channel is a good one to use.) Figure1. Tektronix Oscilloscope generated using Multisim 8 Part II: 1. 2. 3. 4. 5. 6. Connect the circuit shown in Figure 2. Adjust your function generator to a sin wave of a voltage of 5 Vp and 1 kHz frequency Calculate the current flowing in the circuit, Irms = ____________. Calculate the voltage across R1, VR1-rms = ___________. Measure the voltage across R1 and R2. Measure the current flowing in the circuit. Calculated Measured (DMM) Error VR1-rms VR2-rms Irms 1 XFG1 R1 1.0k 4 R2 1.0k 2 Fig.2 Circuit Diagram generated using Multisim 10 7. 8. 9. 10. 11. 12. 13. Turn on your oscilloscope. Set the coupling to 'GND' for both channels. Position CH1 and CH 2 appropriately on the scope so they would not overlap. Connect CH1 probe across the resistor R1. Connect CH2 probe across the resistor R2. Measure VR1rms and VR2rms using the measure function of the oscilloscope. Discuss discrepancy in measurement, if any. Calculated Measured (DMM) Measured (Scope) VR1-rms VR2-rms Irms Part III: 14. Connect CH1 probe across the resistor R1and R2, (across the supply). 15. Connect CH2 probe across the resistor R2. 16. Use the MATH function on your oscilloscope to perform the following operation CH1 -CH2. This yields the voltage across R1. 17. Record VR1rms and VR2rms based on the above step. 18. Discuss discrepancy in measurement, if any. Calculated VR1-rms VR2-rms Irms Measured (DMM) Measured (Scope) Part IV: 19. Connect the circuit shown in Figure 3. XFG1 1 C1 30nF 2 L1 100mH 3 R1 1.0k 4 Figure 3. Circuit Diagram generated using Multisim 10 20. Adjust your function generator for a 5Vrms sine wave with a 300 Hz frequency. 21. Connect CH1 across R1. 22. Fill out Table 1 below. Table 1-Calculated values Frequency Calculated XC Calculated XL Calculated Z Calculated I Calculated VR Measured VR 300 Hz 600 Hz 800 Hz 1kHz 2 kHz 3 kHz 4 kHz 5 kHz 6 kHz 8 kHz 10 kHz 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. Calculate the resonance frequency, fr = ______________ Measure, at resonance, VR= ___________, VC= _________________, VL= ___________ Compare the voltage across the capacitance and inductor. Draw the impedance phasor diagram from Table 1. Draw the voltage phasor diagram from Table 1. Remove CH1 from across R1 and Connect it across the function generator Connect CH2 across R1 Adjust the Volts/DIV for both channels so they are equal Switch the scope to operate in XY format Observe the waveform on the scope. Calculate the phase angle for the different frequencies listed in the table above. When the circuit is purely resistive, the Lissajoux figure should look as shown below 35. In the case of a phase difference, the Lissajoux figure should look as shown below