A system includes a plurality of communication devices and a telephony exchange system. The aim of said invention is to improve the determination of the point of application avoiding the use of sensorial information on an engine. A method for operating the device comprises the steps of i) connecting the orifice and the nozzle or opening in flow communication, ii) filling liquid into the dosing chamber through the orifice, iii) aligning the orifice with the through passage, and iv) ejecting liquid from the dosing chamber through the orifice. The information address can be stored, selected and deleted in the selective call device or remote control device. Therefore, a height dimension of the radiation conductor for attaining resonance at a desired frequency can be made much smaller than in conventional monopole antennas. A comparator compares the read pointer an the write pointer, and the comparison is used to adjust the memory timing.