VERFAHREN UND EINRICHTUNG ZUR BESTIMMUNG VON SCHWINGUNGSEIGENSCHAFTEN SOWIE ZUM BETREIBEN EINES PIEZOELEKTRISCHEN WANDLERS

For the identification of the resonance characteristics of a piezo-electric transducer, an input signal having a variably selectable frequency is divided into two sub-signals of the same frequency to be tuned to one another, one of said sub-signals being independent of and the other thereof being dependent upon the electro-mechanical properties of a piezo-electric tranducer under test. A difference output signal is generated from the two sub-signals, this difference output signal being measured relative to a reference output signal derived from the input signal. The tuning of the two sub-signals in the measurement is undertaken constantly to zero and with a rated value actual value differential control of that part of the difference output signal lying in phase or, alternatively, 180 DEG out of phase with the reference output signal. The remaining part of the difference output signal which is phase-shifted 90 DEG relative to the reference output signal, is used as a measure of the resonance characteristic of the transducer.