Abstract: A keyboard with capacitive keys is operable through a thick dielectric wall which may be integral therewith. The keyboard may be installed inside an agency or store and coupled to a micro-informatic system providing audiovisual information selected at the request of a passer-by on the street operating the keyboard through a thick shop window. The keyboard includes a base panel (1) made of insulating material provided with Cnm electrodes integrated into the panel. with a free running oscillator being associated with each electrode key. A method of scanning the keyboard is provided.