Shed/Log Cabin Alarm

This project is for the design of a shed or log cabin alarm system. This circuit allows for one magnetic door switch and/or a single infrared motion detection sensor.

Note the use of a miniature switched mode power supply module to provide the 5v power supply from the 12v power source. This is to provide better stability during cold and hot weather conditions. From experience a 7805 regulator overheated during the summer!