A telephone messaging system with active security feature is disclosed. Specifically, some of the disclosed example methods, systems, devices andor apparatus relate to semi-automatic andor automatic alignment of mining trucks relative to shovel during mining loading operations. In another set of techniques for a memory partitioned into two sections, blocks which fail in the more error prone partition are transferred to serve as spare blocks in the other partition. Segments of the cable having different core lay lengths may be spaced periodically along the length of the cable, and the periodicity of the spacing may be altered by a jitter distance. Furthermore, the compressor is a centrifugal compressor, the rotational speed of which is directly dependent on the rotational speed of the internal combustion engine, and that the combustion air supply arrangement is arranged in such a way that the sucked-in air is compressed once between the second throttle and the internal combustion engine. The first data terminal is used as a data terminal for a memory card intended for 1-bit data communication to maintain the compatibility with this memory card.