Instructions to Build Door Alarm

Making the Alarm

1. Disconnect one battery wire from the buzzer.
   
2. To make things easier, put the battery and the buzzer on the wood, as shown in diagram 2.
   
3. Use a piece of electrical tape to tape the battery to the wood so that it does not move.
   
4. Get the buzzer and put it at the other corner of the wood and tape it to down, just as in diagram 2.

Now that you have taped the battery and the buzzer to the wood, we will work on the most important part of the burglar alarm, the switch. The burglar alarm switch is a little different from the buzzer switch that you made by disconnecting and connecting the wire at the beginning of this lesson.
Now you want a switch that works easily and more quickly, without you having to make and break the connection with your hands. You need a switch that turns on and off the buzzer depending on a door opening or closing. Making a switch that does this will result in a Burglar Alarm Switch.

The Burglar Alarm Switch

1. First, you will need to wrap the ends of the clothes pin with the non-insulated wire or the insulated wire that you have peeled. Look at diagram 3.
   
   
2. Make sure that the wires touch when the clothes pin closes, as in diagram 4. If the wires don’t touch, then there will be no connection and the alarm will not work.
   
3. After wrapping the wires, connect one of the free ends of the wire to one of the wires coming from the battery.
   
4. Connect the other wire from the pin to the buzzer.
   
   
5. Connect the remaining free wire from the battery to the buzzer (if you have not yet done so when making the buzzer switch, above).
   • Note: If you are confused by now, just look at diagram 5 and connect the wires as shown in the picture.
   
   
6. Test the switch by opening and closing the pin. When the clothes pin is closed, the alarm should sound. If it doesn’t, make sure all the wires are connected and that the clothes pin’s non-insulated wires on the end are touching. If it still does not work, look at diagram 5 and check all the wires again. It should work.
   
   
7. When it is working, you may want to turn it off by placing a small piece of cardboard in between the ends of the pin so as to open the switch and turn off the buzzer. It is annoying to continue working with the buzzer on. (See diagram 6.)
   
8. With the buzzer off, paste the clothes pin to a corner of the wood using crazy glue (see diagram 7).
   
   CAUTION:
   You have to be careful with the glue. It sticks very quickly. Do not touch the glue with your fingers. It might be a good idea to have some nail polish remover handy: if you accidentally get your fingers stuck together, it can dissolve the glue for you.
   
9. Finally, attach the string to the cardboard that you already put between the ends of the pin. When this string is pulled away, the wires in the pin will make contact and the alarm will sound