[en] A variety of heavy ion induced reactions has been studied with the Q3D spectrometer, examples are given. The proportional counter has shown a great ability to identify masses up to A=24 at energies greater than 20 MeV. For lower energies and heavier masses the resolution of the residual energy signal get worse due to the fact that almost all the energy of the particles is lost in the intermediate mylar foil. This is a limitation in the use of the proportional counter. In order to improve the detection along the focal surface we decided to build a detector with the following properties: - a clean geometry without any intermediate foils, - Esub(total) information with a good resolution instead of a residual energy information, - improved ΔE resolution, - wider energy range, 16% instead of approximately 10%, - measurement of the vertical position. The improvements presented above will allow to detect heavier masses and less energizing ions with a better energy resolution