The facial nerve can be stimulated with a biphasic current to unblock certain facial deformities and possibly limit facial pain. The electrical stimulator is a clinical tool that allows, on the one hand, to excite the mastoid foramen, which is a nervous zone located at the level of the lower jaw, and on the other hand, to record the muscular electrical response. This stimulator allows, with the help of electrodes, to generate variable electrical waves. The electrodes are controlled by a current programmable by a PIC 16f84 microcontroller in order to allow clinical flexibility in the programming of the parameters. A display system is also installed to identify clinically the excitatory wave (frequency, amplitude and waveform). We evaluated the muscular response thanks to an electrical detector which, first of all, amplifies the captured signal and then, with the help of a VCO, controls a small loudspeaker which informs us about the position of the excitation electrode in relation to the nerve.