Wideband and ultra-wideband (UWB) technologies have achieved notable progress in recent years. The advent of many UWB sources capable of producing output powers in the GW range allows managing real investigations of the susceptibility of electronic systems and of their protection and hardening against such UWB threats. However, in the meantime, the development of very compact and autonomous UWB sources remains of real interests so as to have at one’s disposal, a easy-touse, transportable experimental devices [1–3]. Traditional uses of the Marx generator have been limited to energy-storage and delivery systems, such as charging capacitors or pulse-forming lines. Recent work with compact Marx generators is moving this technology from these applications to high-power microwave devices (electromagnetic weapons, susceptibility and hardening of electronic systems to transient threats, or UWB radars). With voltage pulse rise times decreasing down to a few hundreds of picoseconds and peak powers reaching several gigawatts, these compact generators have be-