This circuit is an alarm for the home or car door; and a lot more. It employs a magnet and reed switch to trigger the circuit; when the magnet is moved away from the reed switch; the alarm is triggered. An integral piezo sounder produces the alarm sound (100dB). And a PLUS; a relay capable of handling up to 10 amps AC is included and may be connected to turn on or off an appliance; light or external alarm sounder etc. Therefore the circuit could be used to turn on a light whenever a basement or garage door is opened.
