Printer module includes a media processing member and a bumper that is arranged to be adjusted in height to provide for a parallel arrangement of the media processing member with respect to a printer roller. The ultrasonic analog signals which have thus been amplified differently are supplied in each signal path to a respective AD converter which converts the amplified ultrasonic analog signals into digital ultrasonic data, from which a combined digital ultrasonic signal is reconstructed after further processing steps. For example, information about the automatically identified regions may be stored using a conventional datatype with a new layer, or alternatively using a conventional layer with a new datatype, depending on the embodiment. Similarly, rotating the inner ring in a second direction relative to the outer ring decreases the tension exerted on the drum skin. Compared with the prior art, this invention has the following advantages: the volume of used catalyst is greatly reduced. A dielectric layer has at least one common interface with at least a part of the nanoparticles.