We are developing a small-scale recirculator to explore critical beam dynamics issues and demonstrate feasibility of the recirculator concept for heavy ion fusion. The paper summarizes the history of modulator development up to this point and outlines future driver scale modulator requirements. The small modulators currently under development produce bursts of voltage-regulated pulses that range in width from 1 to 45s at amplitudes of 500 volts. These bursts of fifteen pulses occur at repetition rates of 50 to 100kHz. In addition, these rectangular pulses incorporate separate pulses ("ears") at the leading and trailing edges that vary in amplitude and risetime from pulse to pulse. These are used to provide longitudinal beam confinement. Triangular pulses are also available for initial pulse tailoring. Test-stand results of the prototype modulator affirm the validity of the design and multiple units are under construction.