DIY: Alarm Circuits

Most alarm systems consist of one of two different types of models: closed circuit or open circuit. Closed circuit alarms have a constant flow of electricity. Once this circuit is broken, electricity shuts off and automatically turns on the alarm. The open circuit alarm does not have electricity until a trigger has been activated. Once activated, the circuit is complete and the alarm will sound. You can build your own alarm system to protect your home.

One piece of cardboard, about 4 inches by 12 inches
Aluminum foil
Four pieces of insulated wire
Electrical tape
Nine-volt battery
Buzzer
Rug

Instructions

- 1
  Fold the piece of cardboard in half. Wrap aluminum foil around the two ends that touch.
- 2
  Remove the ends off of your insulated wire. The metal should be visible.
- 3
  Attach the end of one wire with one side of the aluminum foil using your electrical tape. Repeat the process with another wire on the other side of the aluminum foil.
- 4
  Connect the positive end of the nine-volt battery with the positive end of your buzzer with one piece of insulated wire.
- 5
  Connect the wire on one side of the aluminum foil to the negative end of the battery. Connect the other wire to the other side to the negative end of the buzzer.
- 6
  Place your piece of cardboard underneath a rug in front of the door. Be certain the rug is light enough to keep the two sides of the aluminum foil from touching. Once the rug is stepped on, the buzzer will sound.

How Do I Get a GE NX-8 to Make a Phone Call?

Information on Security Signs

Home Alarm Systems