1. Hand Calculations (in a manner suitable for submission) For the circuit in Fig. 1 with f = 7.2 khz and a source vin () t 1.

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1 Objectives The purpose of this laboratory project is to introduce to equipment, measurement techniques, and simulations commonly used in AC circuit analysis. In this laboratory session, each student will: 1. Learn how to use an LCR meter to make measurements 2. Learn how to measure phase differences within an AC circuit. 3. Learn to input and analyze AC circuits using SPICE in both the time and frequency domain. 4. Compare calculations, simulations, and experimental measurements. Pre laboratory Work Must be completed and submitted prior to making measurements A. Pre laboratory Analysis for Circuit 1 Fig. 1. Resistive capacitive circuit for analysis. 1. Hand Calculations (in a manner suitable for submission) For the circuit in Fig. 1 with f = 7.2 khz and a source vin () t 1.0cos2 f t V applied at the circuit input (between points A and D), calculate by hand the voltage v 1 (t) at the input and the voltage v 2 (t) at the output (between points B and D). 2. Spice Time Domain Analysis 1) Enter the circuit from Fig. 1 into B2.Spice (labels A, B, and D not required) a) Show node numbers. b) Save this circuit. 2) Add the following instruments: a) Function Generator at the circuit input, that is, between the node corresponding to point A and ground (ref. node 0) with an amplitude of 1.0 (V), a sinusoidal frequency of f = 7.2 khz with no offset. b) Oscilloscope with two traces: Trace 1 across input (check show), Trace 2 across output (between the node corresponding to point B and ground (ref. node 0)). Check Show. 3) Run Simulation (push Double Green Arrows to start a simulation) Note: if you need to make any changes to the simulation set up first stop and reset the simulation. 4) Select Export under the Oscilloscope Set up to create a plot to be saved. Page 1 of 7

2 a) Copy to Graph b) Use Edit Axes to provide proper axis label with units (unclick selection title to allow change). c) Use Edit Plots to change trace colors and thickness. d) Use Horizontal Calipers to denote horizontal scale differences (here delta time measurements) 5) Use Export Graph under the file menu to save the desired figure in final form. 3. Repeat Steps A2 (1 5) for a frequency f = 14.4 khz B. Pre laboratory Analysis for Circuit 2 Fig. 2. Resistive inductive circuit for analysis 1. Hand Calculations (in a manner suitable for submission) For the circuit in Fig. 2 with f = 7.2 khz and a source vin () t 1.0cos2 f t V applied at the circuit input (between points A and D), calculate by hand the voltage v 1 (t) at the input and the voltage v 2 (t) at the output (between points B and D) 2. Spice Time Domain Analysis 1) Enter the circuit from Fig. 2 into B2.Spice (labels A, B, and D not required) a) Show node numbers. b) Save this circuit. 2) Add the following instruments: a) Function Generator at the circuit input, that is, between the node corresponding to point A and ground (ref. node 0) with an amplitude of 1.0 (V), a sinusoidal frequency of f = 7.2 khz with no offset. b) Oscilloscope with two traces: Trace 1 across input (check show), Trace 2 across output (between the node corresponding to point B and ground (ref. node 0)). Check Show. 3) Run Simulation (push Double Green Arrows to start a simulation) (1) The time scale for the oscilloscope should be adjusted so that the minimum number of complete waveforms are displayed. Note: if you need to make any changes to the simulation set up first stop and reset the simulation. 4) Select Export under the Oscilloscope Set up to create a plot to be saved a) Copy to Graph. b) Use Edit Axes to provide proper axis label with units (unclick selection title to allow change). c) Use Edit Plots to change trace colors and thickness. Page 2 of 7

3 d) Use Horizontal Calipers to denote horizontal scale differences (here delta time measurements). (1) Convert the time differences to phase angles. 5) Use Export Graph under the file menu to save the desired figure in final form. 3. Repeat Steps B2 (1 5) for a frequency f = 14.4 khz. C. Operational Amplifier Circuit Design 1. Design an inverting operational amplifier circuit with the following specifications: a) Input Impedance > 2kΩ (take resistor tolerances into account). b) Power Supply: +/ 5VDC c) Vo/Vi = / 5% for a sinusoidal input at 10 khz 2. Verify your design using B2.Spice a) Enter the op amp circuit you designed including power supplies into B2.Spice. b) Simulate using B2.Spice. D. Pre laboratory Submission a) Pre laboratory analysis of circuit 1 i. Hand calculations at 7.2 khz ii. Copy of your B2.Spice time domain results at 7.2 khz iii. Copy of B2.Spice steady state analysis results at 7.2 and 14.4 khz (that is phase and magnitude information). b) Pre laboratory analysis of circuit 2 i. Hand Calculations at 7.2 khz ii. Copy of your B2.Spice time domain results at 7.2 khz iii. Copy of B2.Spice steady state analysis results at 7.2 and 14.4 khz c) Pre laboratory analysis of operational amplifier circuit i. Schematic of op amp circuit that you designed ii. B2.Spice results that verify the specifications were satisfied for a sinusoidal input at 10 khz E. Preparation for Laboratory Measurements 1. Reading a) Oscilloscope: i.read about how to use cursors to measure time differences.(find the manual on EE webpage ofems/pdfs/electrical_engineering_laboratory_manual.pdf). ii.read about how to convert time shifts to phase shifts. b) LCR meter: Read about how to use to make R, L, and C measurements. 2. Obtain the following items: 1. Resistors (values needed = 2.2kΩ and 47Ω) 2. Breadboard 3. Components needed to construct the op amp that you designed in the pre laboratory analysis. You will not receive credit for laboratory measurements unless your pre laboratory analysis is submitted prior to the due date. Page 3 of 7

4 F. Phase Difference Measurement Suppose two sinusoids v 1 (t) and v 2 (t) have the waveforms shown in Fig. 3. Fig. 3 shows two sinusoidal signals phase shifted relative to each other to illustrate the measurement procedure. The phase angle (in degrees) of v 2 (t) relative to v 1 (t), denoted as (V 2 /V 1 ), can be calculated from the time difference (T d ), assuming the frequency is f a : Td ( V2 / V1) Td fp, since period T p = 1/f a and v 2 (t) lags v 1 (t) (hence the Tp negative sign). The value of T d shown in Fig. 3 can be measured with the time cursors. Laboratory Procedure In EGH337: A. Measuring Phase Differences for RC circuits 1. Use the LCR meter to measure the actual resistor and capacitor values that will be used to construct the circuit in Fig Construct the circuit in Fig. 1 on your breadboard. 3. Turn on your oscilloscope and verify proper operation of both scope probes. 4. Attach an oscilloscope probe to CH 1 with the probe tip located at point A and the 5. Attach another oscilloscope probe to CH 2 with the probe tip located at point B and the 6. Adjust your signal generator so that it provides a 7.2 khz input signal (CH 1) at 2V pp 7. Measure the phase and time shift between the waveforms using cursors. (Save an image of the scope trace used to determine phase angle and time shift) 8. Open a Word document and open Intuilink from the computer desktop. a. If the program is not in the Windows menu it is found in: C:\Program Files (x86)\agilent\intuilink\data Capture Page 4 of 7

5 i. The program is named agtdtcpt2.exe Downloading images from the Keysight 1xxx series oscilloscopes. b. In any operation of the Keysight oscilloscope if Rmt appears on the screen press Force Trigger (Local) to enable the oscilloscope inputs. c. With the oscilloscope on start Intuilink Data Capture from Windows. i. Under Instrument select Agilent 1000 Series ii. Under the Set I/O tab, click Find Instrument iii. Under Select Address(es), select the address beginning with USB iv. Click Identify Instrument(s) v. Select the oscilloscope and click OK to close the Find Instrument dialog box vi. Click OK on the Agilent 1000 Series Add In dialog box vii. At this point two windows should appear within the Agilent Intuilink Data Capture window. 1. One is a screen shot that can be copied as an image. a. This can be copied and pasted into a Word document or saved as a png or bmp. (Save this one.) 2. One is an text data file. a. This can be imported and manipulated in a program like Excel. (This can be ignored.) viii. To download another image click on the Get Data icon. 9. Determine the period of the waveforms. 10. Determine the phase shift from the period and the measured phase and time shift. 11. Use the built in phase measurement of the oscilloscope to measure the phase shift. (Found under the Time menu of the Measure functions.) 12. Compare with the values obtained in your pre laboratory analysis. 13. Repeat for a 14.4 khz input signal (CH 1) at 2V peak to peak. B. Measuring Phase Differences for RL circuits 1. Use the LCR meter to measure the actual resistor and inductor values that will be used to construct the circuit in Fig Construct the circuit in Fig. 2 on your breadboard. 3. Attach an oscilloscope probe to CH 1 with the probe tip located at point A and the 4. Attach another oscilloscope probe to CH 2 with the probe tip located at point B and the 5. Adjust your signal generator so that it provides a 7.2 khz input signal at 2V peak to peak. 6. Save a copy of the input and output waveforms from Channels 1 and Measure the phase and time shift between the waveforms using cursors. (Save an image of the scope trace used to determine phase and time shift) 8. Determine the period of the waveforms. 9. Determine the phase shift from the period and the measured phase and time shift. Page 5 of 7

6 10. Use the built in phase measurement of the oscilloscope to measure the phase shift. 11. Compare with the values obtained in your pre laboratory analysis 12. Repeat for a 14.4 khz input signal (CH 1) at 2V peak to peak. C. Design and Construction of an Inverting Op Amp Circuit 1. Build the inverting operational amplifier circuit and document the gain (V o /V i ) and phase at a source frequency of 10 khz (document with a scope image). 2. Experimentally determine the input voltage range for which the specification. a. V o /V i = / 5% is valid (document with scope images). 3. Compare with your pre laboratory analysis. Using the Analog Discovery: A. Measuring Phase Differences for RC circuits 1. Use the Impedance meter to measure and record the actual capacitor values that will be used to construct the circuit in Fig. 1. a. For instructions to measure the inductor and capacitor click on the Help tab for information on the Impedance Analyzer. 2. Measure the actual resistance of the resistor used to construct the circuit in Fig Construct the circuit in Fig. 1 on your breadboard. 4. Connect the waveform generator, W1, to point A. 5. Connect channel 1 of the oscilloscope between points A and D. 6. Connect channel 2 of the oscilloscope between points A and D. 7. Connect the ground wire to point D. 8. Adjust the wave generator so that it provides a 7.2 khz input signal at 2V pp 9. Adjust the waveform display so that between 1 and 3 complete waveforms are displayed so that the input wave fills as much of the screen as possible without going off screen. 10. Measure the phase and time shift between the waveforms using cursors. a. Under the View menu, select X Cursors. b. Add a Normal cursor and place it on a peak or zero crossing of channel 1. c. Add a Delta cursor and place it on a peak or zero crossing (whichever you chose for channel 1) of channel Open a Word document from the computer desktop. 12. Determine the period of the waveforms. 13. Determine the phase shift from the period and the measured phase and time shift. 14. Use the Measuemrent function to determine the phase shift. a. Under the View menu, select Measurements b. Click Add Custom Global c. Click Add to use the built in Phase measurement. 15. Compare with the values obtained in your pre laboratory analysis. 16. Repeat for a 14.4 khz input signal at 2V peak to peak. B. Measuring Phase Differences for RL circuits 1. Use the Impedance meter to measure and record the actual inductor value that will be used to construct the circuit in Fig. 2. Page 6 of 7

7 a. For instructions to measure the inductor and capacitor click on the Help tab for information on the Impedance Analyzer. 2. Measure the actual resistance of the resistor used to construct the circuit in Fig Construct the circuit in Fig. 2 on your breadboard. 4. Connect the waveform generator, W1, to point A. 5. Connect channel 1 of the oscilloscope between points A and D. 6. Connect channel 2 of the oscilloscope between points A and D. 7. Connect the ground wire to point D. 8. Save a copy of the input and output waveforms from Channels 1 and Measure the phase and time shift between the waveforms using cursors. (Save an image of the scope trace used to determine phase and time shift) 10. Determine the period of the waveforms. 11. Determine the phase shift from the period and the measured phase and time shift. 12. Use the built in phase measurement of the oscilloscope to measure the phase shift. 13. Compare with the values obtained in your pre laboratory analysis 14. Repeat for a 14.4 khz input signal (CH 1) at 2V peak to peak. C. Design and Construction of an Inverting Op Amp Circuit 1. Build the inverting operational amplifier circuit and document the gain (V o /V i ) and phase at a source frequency of 10 khz (document with a scope image). 2. Experimentally determine the input voltage range for which the specification. a. V o /V i = / 5% is valid (document with scope images). 3. Compare with your pre laboratory analysis. Check off 1. Show your instructor the collected data. 2. Show the waveform of the op amp circuit on the oscilloscope. 3. Be prepared to answer laboratory related questions. 4. Submit data in Canvas as the data assignment for project 1 (single pdf only). Report Use the Informal Report template as shown in: ofems/pdfs/electrical_engineering_report_formats.pdf 1. Include all measured data (this does not necessarily mean every measurement). 2. Include the following sections: a) Header b) Summary c) Schematics d) Testing e) Discussion 1) Be sure to compare the calculated and simulated results to the measured results. f) References (if used) g) Report should not exceed five pages. Page 7 of 7