Abstract: A traveling wave tube apparatus and method is disclosed. The traveling wave tube includes a slow wave structure such as a helix member. The helix member has an input end for receiving a microwave input signal having a selected power level and an output end for supplying a microwave output signal having a given power level. A microwave source is connected to the input end of the helix member for applying the microwave input signal to the helix member. An electron gun assembly is adjacent the input end of the helix member and has a cathode for injecting electrons as an electron beam through the helix member. A collector assembly is adjacent the output end of the helix member and has at least four collector electrodes for collecting the electrons in the electron beam. The power level of the microwave input signal is selected such that the given power level of the microwave output signal is at least 3 dB lower than the power level of the microwave output signal at saturation.