A single motion sensing assembly device will activate and transmit a signal when a rodent trap is triggered. The single sensor assembly provide a sensing rod attached to one side of a leaf of an open hinge and a magnet affixed to the same leaf on the opposite side. The magnet is positioned adjacent to a reed switch and transmitter which is attached to the opposite leaf of the open hinge. The sensing rod is moved up and down causing the reed switch to activate the transmitter.