We propose to measure and evaluate the response of the pixel detector TimePix at LOHENGRIN for (i) Optimization of detector performance and settings for heavy ion detection, (ii) Spectroscopy of fission fragments and their subsequent decay radiation, (iii) Measurement of charge collection processes in semiconductors. Thanks to the highly selective heavy ion beams of different energy and mass at LOHENGRIN, a number of tasks and studies will be carried out: (a) extend and optimize the detector settings and energy resolution, (b) study the influence of bias voltage on charge collection efficiency and cluster shape, (c) explore the effect of impact direction on charge collection and cluster shape, (d) Investigate the effect of ion mass on charge collection and cluster shape. With these results the detector will be ready for precise spectroscopy studies of fission fragments and their decay radiation.