A pulse power system (1MV, 50kA, and 100ns) based on dual polarity charged Marx generator and Blumlein pulse forming line (PFL) was built to generate high power microwaves. This paper describes the inherent prepulse present with the Blumlein configuration and the mitigation strategies adopted. Further, a qualitative attempt to verify the generation of high power microwave output on the system is presented. © 2008 IEEE.