This board was already assembled and tested, the proposal of this board is to have alarm sound when you forget to close the door, example : you have the baby in your home, to prevent the baby run out of the door, alarm sound will alert you to close the door, you can set delay time from 10second to 160 second.

Technical information:
   - 9VDC battery required. ( not in the package )
   - Alarm ( by Buzzer )
   - Current consume 60mA / 9V when sound alarm and Stand by only 1.9uA
   - 2 Adjustable pots for low tone and high tone of alarm sound
   - 1 pot to adjust the delay time 10-160seconds. / Disable the delay by put JP1 jumper
   - Included the magnetic sensors in the package. ( see the below image )
   - Comes with the schematic.
   - PCB size 2.81" x 1.84"

Download User Manual