7CONTROLLING THINGS WITH ELECTRICITY
Electronic components let you build smart things, like a lamp that turns on when it gets dark or a door that opens automatically when you approach it. In this chapter, you’ll learn about a new component that will help you build such smart objects: the transistor.
The previous chapter showed you how to solder, and this chapter’s projects—a touch sensor and an alarm that wakes you up when the sun rises—will give you more chances to practice your soldering skills. All you need for each project is the transistor and a few additional components.
MEET THE TRANSISTOR
The transistor is the most important component ...