This book deals with digital processing of output signals of impulse radiation detectors. Most of the attention was paid to detectors whose output impulses carry their amplitude information about energy left by the detected particle in the detector and the time course of output impulses contains information about the type of the particle being detected. This types of detectors are used mainly in spectrometry of a mixed field of neutrons and gamma radiation. The work presents results of procedures when the output signal from a detector is digitalized immediately behind the output and further processed only numerically. Digitization was realized with several commercially obtained devices – digitizers. Parameters leading to optimal data for further software processing, such as a suitable sampling frequency, output quantization resolution, reach of the required dynamic range etc., were searched for. The software processing leads to determination of an amplitude of each impulse (the range of deposited energy of the interacting particle in the detector) and type of the detecting particle. For this purpose a number of mathematical methods leading to setting of both parameters were tested.