Transient signal measurements are bandwidth limited by present digitizer technology. If a transient signal can be stored in a gain-clamped regenerative delay line, such a signal can be regeneratively sampled, resulting in about an order of magnitude increase in measurement bandwidth. The approach involves converting electrical signals to optical signals with high fidelity, injecting such signals into a fiber-optic delay line, and then sampling injected signals repetitively, with signal generation provided by an erbium-doped gain-clamped fiber amplifier. Moreover, signal regeneration can be either steady state (i.e., amplification on each pass) or switched (i.e., amplification after signal levels have dropped significantly).
 The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.