magnet

[RoboMoon]

magnets parameters ...

[Soeren]

Hi,

Look here

[RoboMoon]

Thanks Soeren

[ballbreaker]

the basics are really easy you can make a simple one with a reed switch that opens when placed near magnet, a magnet, a battery and a buzzer or light or whatever. you just connect  the battery with the buzzer and the buzzer to the reed switch and the reed switch back at the battery and connect the circuit to the wall and the magnet to the door
that's the simplest form you can use transistor if you want but it's not necessary.

[RoboMoon]

Thanks ballbreaker

[ballbreaker]

- first you have to find a reed switch which is normally closed. (form c)
which is not as easy to find but it exists.
then you need to buy:

1 magnet , 1 battery pack , your batteries for the pack , an on/off switch and wire.

- first take your batteries and put them in the battery pack.
- connect the on/off switch with one wire from the battery pack.
- connect the reed switch one end to the on/off switch and the other to the battery pack.
- stick the magnet to the door and the circuit to the wall near the door and make sure  the reed switch and the magnet are close when the door is closed.

(make sure the length of your wires are enough to place it easily.)
 
Hope that helped.