Abstract: A signal scrambling system is provided in which the scrambler includes a transition limiter which limits the size of changes in the amplitude of the input clear signal, a device for generating a pseudo random signal and combining the pseudo random and clear signals, and a transposer for reducing the bandwidth of the channel needed for the scrambled signal. The descrambler includes another pseudo random signal generator and device for combining the random signal with the received scrambled signal, as well as another transposer, for recovering a descrambled signal. The system minimizes the power bandwidth of the channel necessary to transmit accurately the scrambled signal which contains no vestiges, not even an average intensity, of the original input signal.