This page is still under construction.
Check out the video below for a tutorial on how to build this project.
Parts list:
Schematic:
When you build the circuit do not put R3 resistor in untill last, Start with a high value (around 100k) then power up the circuit with between 6 and 12 volts. with the trap open so the alarm would go off start trying smaller value resistors untill the alarm goes off.