Abstract : The results of four tests on an explosive-driven sweeping-wave coaxial generator are reported. The first shot of the series used a capacitor bank to supply the initial current. The remaining three shots used an explosive-driven sweeping-wave helical generator to boost the initial current. On the final shot,a peak current of 50 MA was reached in a 12 nH load,corresponding to a peak energy of 15 MJ. The peak power was 1.5 TW and the final current-doubling time was 12.5 microsecond In addition to conventional Rogowsky loops, Faraday rotation sensors were employed to measure the current. Arrays of microballoon optical-fiber pins were used to measure the shape of the armature under the action of the magnetic forces in the generator. The coaxial generator should be capable of achieving still higher output energies if higher input energies are provided.