Objective of the lab experiment:

Get_Classical_Lines.vi

Connect the Elvis II board to the computer running LabVIEW using the supplied USB cable, turn on power to the Elvis II

board.

Load the supplied LabVIEW virtual instrument file, Dynamic_signal_analyzer_LabVIEW_2010.vi into LabVIEW. You may

see a dependency warning as seen below. This is normal; just click Ignore.

ECET345 Signals and Systems—Lab #9

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Professor Ajeet Singh, Ph.D

Richard Butler, EET

Step #5

The DAQ usually needs to be configured with the correct input channels before it will work. To do this, go to the block

diagram in LabVIEW by going to the Window menu and selecting Show Block Diagram.

Find the DAQ Assistant icon and double click it with the mouse.

ECET345 Signals and Systems—Lab #9

Page 11

Professor Ajeet Singh, Ph.D

Richard Butler, EET

Press the Run button at the top to see whether the signal is seen at the top. If not, a DAQ Assistant error will show at the

bottom. To select the correct input channels, first delete the existing ones by using the red X button. To add the

channels, uses the blue + button, click Voltage, and select the two channels as shown on the right.

Click the Run button again to verify that the signals are coming through then close the DAQ assistant and return to the

front panel. (You can close the block diagram.)

Step #6

In the front panel window of the vi, set Maximum Frequency to the maximum frequency you have set on the sweep

generator.

ECET345 Signals and Systems—Lab #9

Page 12

Professor Ajeet Singh, Ph.D

Richard Butler, EET

Now press the Play or Run button at the top of the screen as shown below.

You should see four large graphs on the screen in the front panel window of LabVIEW. The two on the right are the time

domain (oscilloscopic) graphs of input and output signals from the filter. The two graphs on the left represent magnitude

and phase parts of frequency response (Bode plot).

Give the program a few averaging iterations to average the frequency response calculations in repeated sweeps. This

will help remove noise from the measurement because random noise averages to zero. After a clean measurement has

been completed, you can use the Print Screen key to copy the graphs and paste them into MS Word. Experience has

shown that if parts of frequency response graphs are not clean, then sometimes changing the sweep time helps out.

Typical sweep times shall be in 1-2-second ranges.