Introduction 1
About This Book 1
About You 2
About the Icons 2
Updates 3
The First Step 3
Project 1: Shopping Spree 4
Plan Your Shopping Spree. 4
Budget 6
Electronic Components and Accessories 10
Tools and Supplies 15
Project 2: Pocket Flashlight 18
Get Prepared 19
Battery 19
Light-emitting diode (LED) 20
Resistor 21
Build the Flashlight Circuit 22
Connect the resistor to the battery 22
Wrap tape around the positive terminal 23
Add a foam cutout 24
Connect the LED to the battery 25
Wrap tape around the negative terminal 26
Test Your Circuit 26
Add a Cover 27
Project 3: Red Light, Green Light 30
Breadboarding 31
Gather Supplies 32
Get to Know New Parts 34
Battery clip 34
Jumper wire 34
Slide switch 39
Breadboard Your Circuit 40
Track Down Problems 45
What's Really Happening? 45
Improve Your Circuit 46
Connect the power rails 46
Add a power switch 47
Project 4: Brainy Nightlight 50
Collect Parts 51
A Simple Sensor 52
The Tiny, Yet Powerful, Transistor 53
Transistors and faucets 54
Explore two transistors 55
Build the Circuit 58
Test Your Nightlight Circuit 65
Make Adjustments 66
Nightlight turns on when it shouldn't 66
Nightlight doesn't turn on when it should 67
Nightlight doesn't turn on at all 68
Project 5: Railroad Crossing 70
What's a Capacitor? 70
Check Out Your Capacitors 72
What's an Integrated Circuit? 73
Meet the 555 Timer 75
Collect Components and Tools 77
Build the Railroad Crossing Circuit 78
Operate the Railroad Crossing Circuit 85
Project 6: Sound Effects 86
Mini-Speaker 86
Gather the Parts You Need 87
Prepare Your Speaker 88
The Plan 90
Build the Tone Generator 91
Test Your Tone Generator 96
Modify Your Circuit 96
Create Sound Effects 97
Project 7: Radio 99
Plan Your Mission. 102
Homemade Tuner 103
Make an inductor 104
Make a variable capacitor 107
Meet Your Radio Signal Detector 111
Check Out Your Earphone 111
Collect Parts and Tools 112
Work Close to the (Earth) Ground 113
Prepare a Radio Platform 114
Build the Radio 115
Listen to Your Radio 119
