An induction generator for a radio switch having a magnet element as well as an induction coil with a coil core, characterized in that the coil core is U-shaped, wherein a first contact position and a second contact position for the magnet element are defined on the limbs of the coil core, with a flux direction reversal taking place in each case in the coil core when a change takes place between said positions, wherein the magnet element is arranged such that it can move in a defined manner linearly between the contact positions on the induction generator in a direction in which the limbs are adjacent to one another.