The present invention provides a method of transmitting electronic communication where the sender includes an instruction set with the electronic communication. In one embodiment, a system includes a proximity detection unit and a transducer proximate to a selected structural portion of an aircraft, the proximity detection unit being operable to emit ranging signals through the transducer and to receive reflected signals through the transducer to determine the position of an object within a ranging area adjacent to the structural portion. The first conversion circuit receives the gray code signals from the holding circuit and converts the received gray code signals into first binary code signals. The modulator is capable of providing the modulation current to the semiconductor laser, with the modulation current corresponding to an input data signal. The width may be constant through the metering and diverging sections. The transversely extending member has end portions which are inwardly tapered relative to the central portions of the member and towards the adjacent ends of the member.