How To Build an Alarm Pad

Fold the aluminum foil into a 6-inch by 8-inch square. Use the ruler and your hands to fold the foil.

Uncover the ends of the wire by removing the outer plastic or rubber-like covering with the help of a small knife or sharp scissors. Attach the open end of the wire to the battery by twisting it around the negative pole of the battery.

Stick the other end of the wire to one side of the aluminum foil with help of cellophane tape. Make sure that the metallic part of the wire touches the aluminum foil completely.

Remove the outer cover of the wires of the mini buzzer with the knife or scissors that you used in Step 2. Twist the open end of the black buzzer wire around the tip of a large paper clip. Attach the other paper clips to the tail of the first clip.

Connect the open part of the red wire of the mini buzzer to the battery by twisting it around its positive terminal. Check the connections of your alarm pad by placing the free tip of the paper clip chain on the aluminum foil. The buzzer should make its characteristic sound if the connections are correct.

Lay the paper clip chain on the floor where you want the movement to be detected. For example, if you want to detect the movement around your back door, you may choose to place the chain under the doormat near the entrance. Position the two straws parallel to each other, about 1 to 2 inches on either side of the paper clip chain. Use cellophane tape to fix the straws and chain to the floor and prevent them from moving. The tail should be straight and tensed for optimal results. Fix the other ends of the paper clip tail as well.

Place the aluminum foil on top of the straws so that it does not touch the paper clip chain. Place the doormat on top of the aluminum foil. Hide the battery and buzzer system behind the door or a pot, or any other object of your choice.