Single-shot High Power Microwave (HPM) systems are of particular interest in the defense industry for applications such as electronic warfare. Virtual Cathode Oscillators (vircators) are manufactured from relatively simple and inexpensive components, which make them ideal candidates in single-shot systems. The Flux Compression Generator (FCG) is an attractive driver for these systems due to its potential for high energy amplification and inherent single-shot nature. A self-contained (battery operated prime power), compact (0.038 m 3), FCG-based power delivery system has been developed that is capable of delivering gigawatts of power to a vircator. Experiments were conducted with the delivery system connected to a resistive dummy load and then to a reflex-triode vircator. In order to optimize the performance of the vircator when driven by the power delivery system, a second experimental setup was constructed using a Marx-generator based system operating at similar voltages and rise-times. Performance measures of the delivery system when discharged into a resistive load will be presented, as well as vircator output power levels and waveforms from both experimental setups.