[en] Experimental results obtained with an ECR ion source (the experiments were made at SIG Centre d'Etudes Nucleaires, Grenoble, France within a French-Swedish collaboration project on negative ions, supported by the European communities) in a new magnetic field geometry for maximum H- ion plasma volume production are presented. The measurements were done on extracted positive and negative currents. An extracted H- ion current density higher than 0.5 mA/cm2 was found. (author)