Introduction

Resistor-Capacitor Timing Basics

In electronics, sometimes we want to keep a device on for a certain amount of time even when an electrical switch is turned off. Ordinary pushbuttons used to turn electronic devices on and off can easily be operated by a timed delay switch. How awesome would it be to create such a device to delay turning off a simple LED? Such a gadget could be used to trick your friends, family, or even the local Makerspace when they see the LED staying on after the pushbutton has been released. With a few electronic components, you can make an LED (light-emitting diode) stay on for a few extra seconds when a pushbutton switch is turned off. Figure 1-1 shows an assembled Trick Switch. The electronic components required to build the Trick Switch are shown in the Parts List.