The generation of surface acoustic waves by interdigital transducers in materials with high and strain‐dependent dielectric constants, which are not necessarily piezoelectric, was studied theoretically using Lamb’s integral‐solution method and the flat‐field approximation of Tseng for the solutions of the wave equation. The influence of the dependence of the dielectric constant on the strain was considered in the approximation given by Pekar and Ogg. As a result, a transducer gain proportional to an applied dc field has been obtained. With respect to the frequency responses, an increased output at higher odd harmonics as compared to transducers on piezoelectric crystals was found. The transducers are shown to be tunable because of a stiffening of the surface‐wave velocity by the applied field. Thus, amplitude modulation and frequency modulation should be possible in a simple manner.