A modulator switch composed of stacks of high voltage switching devices connected in series are fired substantially simultaneously to provide pulsed, high voltage switching capable of providing megajoules of energy. The switching devices are fired by a trigger box that is clocked to provide a pulsed signal to each of the switching devices. The trigger box generally consists of a triggering or driver circuit and a pulse generating circuit. These circuits are electrically isolated from one another using suitable shielding and spacing. The pulsed output of the trigger box is fed to the switching devices across low inductance twisted cabling that is passed through toroidal transformers connected to the inputs of the switching devices. Varistors are clamped across each stack of switching devices to provide over-voltage protection for the switching devices.
REFERENCE TO GOVERNMENT GRANT
 This invention was made with United States government support awarded by the Department of Energy (DE-FC02-05ER54814, 144-NH87). The United States has certain rights in this invention.