The evolution of pulsed modulators from the Marx generator to the Solid State Marx modulator and beyond

The pulsed modulator has evolved from the early spark gap Mark Generators thru many different design forms to the present in which the Marx design returns using Solid State switches. The paper will chronicle the different types of pulsed modulators, including hard tube/switched modulators, pulse forming network modulators, induction/fractional turn modulators and Marx type modulators. The use of the various types of modulators for short and long pulse operation is reviewed. The advantages and disadvantages of the different types of modulators are evaluated and their possible use in present requirements and future applications is discussed. In addition, the paper speculates on the possible evolutional direction in which modulators might change or develop in the future.