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There are serious contradictions in the theoretical and experimental data on the prompt fission neutron spectra for a number of fissile isotopes. Particularly large discrepancies are observed in the experimental data for the region of low (<0.5 MeV) and high (> 6 MeV) neutron energies. This is due to the large influence of systematic errors on the results of the neutron spectra measurements for these energy ranges, among which the main ones are the influence of the scattered neutrons and gamma-rays on the shape of the measured spectrum, the quality of n/γ separation, and the influence of the uncertainty in determining the time mark when the time-of-flight method used. The aim of this work was to create a universal digital spectrometer of the prompt fission neutrons. The spectrometer includes: the organic scintillator based on p-terphenyl for the fast neutron detection; slow neutron detector based on the inorganic scintillator Cs2YLiCl6:Ce, fission chamber. Using a digital approach to processing signals from different elements of the detector, it is possible to solve problems related to the suppression of background events and systematic errors in determining the occurrence time of the signals at a new qualitative level. The paper presents the results of test measurements in which a number of important characteristics of the spectrometer were determined - its detection efficiency, light output, quality of gamma-background suppression, time characteristics.
