The invention relates to a signal generator for generating periodic signals for a measuring apparatus (1) in automation technology, wherein the signals have successive discrete signal frequencies which are within a predefined frequency range, having a control and/or computing unit (4), having a clock generator (6), wherein the clock generator (6) provides a constant sampling frequency which is greater than the maximum discrete signal frequency in the predefined frequency range, having a storage unit (7) in which the amplitude values of the corresponding periodic signals are or can be stored for each of the discrete signal frequencies on the basis of the sampling frequency, wherein the control and/or computing unit (4) gradually reads the stored or storable amplitude values of the discrete frequencies from the storage unit (7) at the sampling frequency of the clock generator (6) and generates the periodic signals or forwards the latter for generation, and having a static filter unit (12) with a cut-off frequency which is above the maximum signal frequency and removes the frequency components caused by sampling.