Understanding Signals
Student Guide
VERSION 1.0
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Table of Contents ·
Page i
Table of Contents
Preface........................................................................................................................iii
Copyright and Reproduction .......................................................................................... iv
Foreign Translations ...................................................................................................... iv
Special Contributors ...................................................................................................... iv
Chapter #1: Oscilloscope Basics..............................................................................1
What is an Oscilloscope? ...............................................................................................1
How Does an Oscilloscope Work? .................................................................................2
Running the OPTAscope 81M for the First Time............................................................5
Plot Area ....................................................................................................................6
Horizontal and Vertical Dials, Channel and Run/Stop Buttons ..................................7
Plot Area Indicator......................................................................................................9
Display Screen .........................................................................................................10
Files / Settings Tab ..................................................................................................10
Trigger Tab...............................................................................................................11
Cursors Tab .............................................................................................................12
Measurements Tab ..................................................................................................13
Activity #1: Viewing High and Low Signals ...................................................................14
Activity #2: Using the Horizontal Dial and Edge Triggering ..........................................18
Summary ......................................................................................................................21
Exercises ......................................................................................................................21
Further Investigation .....................................................................................................21
Chapter #2: Servo Pulse Square Waves ................................................................23
Pulse Width Modulation and Hobby Servos .................................................................23
Activity #1: Measuring Pulses for Servo Control...........................................................25
Activity #2: Measuring Time Varying Servo Pulse Widths ............................................31
Summary ......................................................................................................................33
Exercises ......................................................................................................................33
Further Investigation .....................................................................................................33
Chapter #3: Sine Waves...........................................................................................35
Sine Waves with the BASIC Stamp FREQOUT Command..........................................35
Activity #1: Sine Wave Triggering.................................................................................36
Activity #2: Sine Wave Frequency and Amplitude Measurement .................................41
Activity #3: Dual Sine Wave Measurement...................................................................43
Summary ......................................................................................................................46
Exercises ......................................................................................................................47
Further Investigation .....................................................................................................48