Electronic component for converting conventional Märklin H0 locomotives to the Delta multi-train control system. This decoder is suitable for locomotives with the Märklin standard motor (flat-commutator motor or drum-style commutator motor), especially for locomotives with Märklin Telex couplers. A locomotive converted with this module can be operated with a conventional train control transformer, the Delta Control, Delta Control 4 f, Delta Station or Märklin Digital. The decoder has switches for setting the mode of operation and the address for multi-train operation. It also has electronic direction reversing. An auxiliary function (example: Telex couplers) can be turned on and off when the direction is changed twice.