An electromechanical device operating at high voltage (125-l30,000 volts DC) which focuses a beam of high-energy deuterons on a target surface containing tritium. [[Nuclear]] fusion of the deuteron ions and target atoms produces high-energy (14-MeV) [[neutron|neutrons]]. The neutron [[radiation]] can be controlled in precise cyclic bursts or pulses, with time in between pulses for the measurement of induced-[[radioactivity]] and [[decay time|decay-time]] schemes.