Chapter 6 Electronics Elements (Detailed Discussion)
The basic elements of most current alarm and access control systems are discussed in the sections that follow.
Identification devices include card/key/barcode1/radio frequency identification readers, keypads, and biometric2 readers. As introduced in Chapter 5, access control systems can determine your identity by what you know, by what you have, or by who you are.
The most basic types of identification (ID) readers are keypads. Basic keypads are simple 12-digit keypads that contain the numbers 0-9 and * and # signs (Fig. 6-1). The most desirable attributes of keypads are that they are simple to use and they are cheap. The most undesirable ...