Measuring and characterizing pulsed RF signals used in radar applications present unique challenges. Unlike communication signals, pulsed radar signals are "on" for a short time followed by a long "off" period, during "on" time the system transmits anywhere from kilowatts to megawatts of power. The high power pulsing can stress the power amplifier (PA) in a number of ways both during the on/off transitions and during prolonged "on" periods. As new PA device technologies are introduced, latest one being GaN, the behavior of the amplifier needs to be thoroughly tested and evaluated. Given the time domain nature of the pulsed RF signal, the best way to observe the performance of the amplifier is through time domain signal analysis. This article explains why the peak power meter is a must have test instrument for characterizing the behavior of pulsed RF power amplifiers (PA) used in radar systems