We report the development of a system to feed pulsed magnetic stress to biological samples. The device is based on a RLC circuit that transforms the energy stored in a high voltage capacitor into a magnetic field inside a coil. The field has been characterized and we found that charging the capacitor with 24 kV results in a peak field of 0.4 T. In order to test its effect, we applied such a stress to the Drosophila melanogaster model and we examined its bio-effects. We analysed, in the germ cells, the effects on the control of specific DNA repetitive sequences that are activated after different environmental stresses. The deregulation of these sequences causes genomic instability and chromosomes breaks leading to sterility. The magnetic field treatment did not produce effects on repetitive sequences in the germ cells of Drosophila. Hence, this field doesn't produce deleterious effects linked to repetitive sequences …