This paper presents the design and implementation of a high frequency switching power converter with a large voltage gain and air core inductors. Specifically, we demonstrate a 40 W, 30 V to 300 V dc-dc converter switching at 27.12 MHz. Operating at this frequency reduces bulk energy storage over conventional low frequency designs and allows for fast transient response. We implement a resonant converter based on the Φ2 inverter of . In this paper, we evaluate and compare two rectifier topologies with lower voltage stress than the class E rectifiers described in , to get large voltage ratios. Unique to this design is the ability to provide short bursts of high voltage while promising excellent performance and high power density.