An electricity meter comprises a conductor having a substantially planar surface; and a carrier for carrying a sensor component for enabling detection of current flowing in the conductor, wherein the carrier is spaced from the planar surface of the conductor by an arrangement of at least three spacing elements. The surface is adapted for outward flow of a thin film of a liquid phase reactant thereacross when supplied thereto as the surface is rotated. The speech signal is then segmented into pitch-synchronous frames. The present invention further provides hybridomas that produce and secrete anti-stilbene antibodies.