ECET 3600 Final Project Report

7/27/2019 ECET 3600 Final Project Report

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FINAL PROJECT: CAT SYSTEM

PREPARED BY

In partial fulfillment of the requirements forECET 3600

PREPARED BY:

APPROVED BY:

April 22, 2013

SOUTHERN POLYTECHNIC STATE

UNIVERSITY


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Table of contents

Section Title Page

1. INTRODUCTION ................................................................................... 1

1.1. Front Panel Display.................................................................................. 1

1.1.1 Start Frequency ........................................................................................ 1

1.1.2 Stop Frequency ........................................................................................ 11.1.3 Number of Measurements ........................................................................ 2

1.1.4 Progress Completed Indicator .................................................................. 2

1.1.5 Data Table ................................................................................................ 2

1.1.6 Analysis Front Panel ............................................................................... 31.1.6.1 Maximum Gain ....................................................................................... 3

1.1.6.2 Maximum Gain Frequency ..................................................................... 3

1.1.6.3 F1 Cutoff ................................................................................................. 4

1.1.6.4 F2 Cutoff ................................................................................................. 41.1.6.5 Bandwidth ............................................................................................... 4

1.1.6.6 Amplifier Graph ...................................................................................... 4

2. INSTRUCTIONS ..................................................................................... 5

2.1 Opening the VI ......................................................................................... 5

2.2 Components and Connections .................................................................. 5

2.3 Develop the Circuit .................................................................................. 52.4 Select a Start and Stop Frequency ........................................................... 5

2.5 Select the Number of Measurements ....................................................... 6

2.6 Run CAT System ..................................................................................... 6

2.7 View the Data Table ................................................................................ 6

2.8 View the Analysis Panel .......................................................................... 6

3. STATE DIAGRAM ................................................................................. 7

4. CONCLUSION ........................................................................................ 8

APPENDIX A MAIN VI .................................................................................................. 9

APPENDIX B SUB VI..................................................................................................... 10


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1. INTRODUCTION

1.1 FRONT PANEL DISPLAY

The initial front panel in LabVIEW for the CAT system program contains different user controlsand indicators used during execution. The specific tools seen in the front panel are discussed in

detail in the following.

Figure 1Front Panel Display

1.1.1 START FREQUENCY. The start frequency is a user control used to set thebeginning frequency received by the Function Generator.

Figure 2- Start Frequency Control

1.1.2 STOP FREQUENCY. The stop frequency control is a user control used to set theending frequency received by the Function Generator.

Figure 3- Stop Frequency Control


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1.1.3 NUMBER OF MEASUREMENTS. The number of measurements control is a usercontrol used to determine the amount of measurements in between the start frequency

and the stop frequency. The number of measurements are scaled according to the set

frequencies.

Figure 4Number of Measurements Control

1.1.4 PROGRESS COMPLETED INDICATOR. The progress completed indicator detailsthe amount of execution completed in collecting the required measurements by

promptly filling a progress bar as the program is executed to collect themeasurements.

Figure 5- Progress Completed Indicator

1.1.5 DATA TABLE. The data table contains the following columns respectively fromright to left: given data points, the measured frequency in hertz, the measured voltage

in volts peak to peak and the voltage gain in decibels.

Figure 6- Data Table


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1.1.6 ANALYSIS FRONT PANEL. The Analysis Panel is part of a complement Sub VIwhich calculates the response of the given Band-pass filter using the measured values

recorded in the data table (Figure 5).

Figure 7- Analysis Front Panel

1.1.6.1 Maximum Gain. The maximum gain of the Band-pass Filter is calculated and shownin decibels inside this indicator.

Figure 8- Maximum Gain Indicator

1.1.6.2 Maximum Gain Frequency. The maximum gain frequency is calculated and shown inHertz inside the Maximum gain frequency indicator.

Figure 9- Maximum Gain Frequency Indicator


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1.1.6.3 F1 Cutoff. The first cutoff frequency is calculated and shown in Hertz inside the F1Cutoff indicator.

Figure 10- F1 Cutoff Indicator

1.1.6.4 F2 Cutoff. The first cutoff frequency is calculated and shown in Hertz inside the F2Cutoff indicator.

Figure 11- F2 Cutoff Indicator

1.1.6.5 Bandwidth. The Bandwidth is calculated and shown in Hertz inside the Bandwidthindicator.

Figure 12- Bandwith Indicator

1.1.6.6 Amplifier Graph. The Amplifier graph plots the gain response versus the frequencyapplied inside a logarithmic scaled graph.

Figure 13- Amplifier Graph


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2 INSTRUCTIONS.

2.1 OPENING THE VI

2.1.1 Open the VI using the LabVIEW programming software.

2.2 COMPONENTS AND CONNECTIONS

2.2.1 The CAT system VI uses three different devices which include a function generator, aDMM for measurement, and a DC voltage generator to run the filter.

2.2.2 Since the GPIB connection infrastructure will be used, make sure the functiongenerator and DMM are securely connected through GPIB and that the computer

recognizes the devices.

2.3 DEVELOP THE CIRCUIT

2.3.1 Develop the circuitry for the Band-pass filter to be tested. This will be considered theDUT by the CAT system.

Figure 13- Example Filter Circuit

2.4 SELECT A START AND STOP FREQUENCY

2.4.1 In the main VI front panel, select a start frequency using the Start Frequency control(Section 1.1.1) and a stop frequency using the Stop Frequency control (Section 1.1.2).

Figure 14- Select Start & Stop Frequencies


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2.5 SELECT THE NUMBER OF MEASUREMENTS

2.5.1 Remain in the main VI front panel to select the number of measurements using theNumber of Measurements control (Section 1.1.3) in between the already selected start

and stop frequency values.

Figure 15- Select Number of Measurements

2.6 RUN CAT SYSTEM

2.6.1 After all devices and circuits are connected, run the computer-aided test to record theresponse from the Band-pass Filter.

Figure 16- Run CAT System

2.7 VIEW THE DATA TABLE

2.7.1 The Data Table (Section 1.1.5) is a real time representation of the measurements andchanges occurring during the CAT system execution. In this chart data points,

frequency, measured voltage and measured gain are all recorded.

2.8 VIEW THE ANALYSIS PANEL

2.8.1 After the CAT system execution, The Analysis Panel (Section 1.1.6) displays theimportant calculated values of the Band-pass filter response. This panel calculates theresponse from the recorded measurements inside the data table, and uses these values

to plot the gain versus frequency response inside a logarithmic scaled graph.


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3 STATE DIAGRAM

Enter Start & StopFrequency and Number

of Measurements

Determine the scale

factor for givennumber of

measurements

Write frequency to

function generator

Measure Circuit Vout

from DMM

Calculate measured

responses in sub VI andplace them in arrays

Plot Measured Gain

and Frequency inAnalysis Graph

Add the calculated

Scale Factor to theused Frequency and

return to write to

FGEN. If the Frequency is >

Stop Frequency

Find the maximumgain, the maximum

gain frequency inside

the subVI arrays

Calculate and display

F1, F2 and Bandwidht.

If Error found display

required message.Return to read from

DMM if corrected.

If Error found displayrequired message.Return to write to

FGEN if corrected.

If Start Frequency >Stop Frequency Errorappears and asks for

new frequency.


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4 CONCLUSION

The final result of the CAT system provides an accurate measurement and calculation of theresponse given by the Band-pass filter. The DUT undergoes simple evaluation to determine the

cutoff frequencies, the maximum gain and the frequency which provides the maximum gain. The

values plotted in the logarithmic scale give an accurate track to the response as the filter reachesits optimum gain. The testing of the reaction to different frequencies in a Band-pass filter allows

to develop computer aided testing, which minimizes human error and increases the level of

accuracy and efficiency in device testing.


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APPENDIX A

Main VI Front Panel

Main VI Block Diagram


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APPENDIX B

Sub VI Front Panel

Sub VI Block Diagram

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ECET 3600 Final Project Report