To manufacture a connecting rod including positioning grooves having a function of positioning a bearing metal at low cost. A potential distribution having a plurality of steps is formed in the charge accumulation region, and the further away from the transfer unit a step of the plurality of steps is, the greater the magnitude of the step is. An estimated value f\u2032, which is characteristic of the sought carrier frequency f, can be determined from knowledge of the values of at least one value pair e and e where k1<kmax<k2, and of the specific test frequency fkmax. Thus, a compact interference suppressor device, which can be produced in a cost-effective way and is easy to install, is achieved. The resonator may comprise two beams connected at or near one end by a yoke which provides a clamped condition of the resonator at said one end and connected at or near another end by said element.