Abstract: A handling apparatus comprising an offset sampling module and a digital processing module is described herein. The offset sampling module is configured to provide a sampled signal by sampling at least one signal at a sampling frequency that is offset from a fundamental frequency of the signal by an offset factor; and the digital processing module configured to convert the sampled signal into a frequency domain signal. The handling apparatus further includes an authentication module to determine at least one characteristic property based at least on the frequency domain signal; and to classify the inserted item of value based on the determination.