CHAPTER 14
Careful What You Reach For! Create a Touch-Activated Alarm |  |
IN EXPERIMENT 10, YOU LEARNED HOW to make a pressure-sensitive mat and connect it to an alarm circuit that triggers when someone stands on the mat. But what happens if the crafty burglar or snooper manages to get past your pressure-sensitive mat without setting the alarm off, and is then heading for your private stuff, such as your journal? You’ll need to find another method of security to stop the snooper in his or her tracks.
This experiment shows you how to make an alarm circuit that’s triggered by the crafty snooper touching an object. The touch-activated alarm mounted in ...