Abstract: The invention is primarily concerned with measuring the frequency response of a regenerator in a digital transmission system. The method and apparatus provide for a variable pulse to be inserted in a sequence of pulses representative of normal traffic through the system and superimposition of a sinusoidal signal on the variable pulse. Results can be plotted from passing a number of sequences through the regenerator and varying the amplitude and/or frequency of the sinusoidal signal and varying the pulse.

Abstract: This invention relates to method and apparatus for measuring noise margins in digital transmission systems. The method requires the introduction of a variable pulse into a sequence of pulses which represents normal traffic, varying a parameter of the pulse, detecting the pulse, and accumulating information concerning the variations to determine probability distribution of the deviations produced by measuring the variations relative to a standard. The apparatus includes means for introducing the variable pulse into a sequence of pulses and for observing and recording detection of the variable pulse in each sequence to compile a probability distribution of the aforementioned deviations.