Purcell reflects on his work on counter-mortar radar and K-band experimental radar. He also takes the opportunity to clear Rabi's name in the controversy around K-band wavelength choice by describing how that decision was made and taking full responsibility for the problems they encountered. Describing the atmosphere at Rad Lab as ebullient, he fondly recalls the pressure of war deadlines, the challenge of learning by doing and his impressions of DuBridge, Loomis, and Rabi.