Abstract: A system for processing the signals from a gamma or other radiation detector through a charge-sensitive preamplifier, makes use of a fast analog to digital converter at the input, preferably downstream of an anti-aliasing filter, and circuitry for the deconvolution of the signal in which the preamplifier transfer function is convoluted with the charge distribution function The deconvolution results which are free from any charge related to any radiation event are averaged and subtracted from the averaged value of the deconvolution results, which results contain completely the charge of the event under processing, and the subtracted signal through a register provides the output. The system represents a significant improvement with respect to the ballistic deficit suppression and with respect to the noise index-counting rate factor allowing a significant improvement in the counting rate for a given noise level or a higher resolution for a given counting rate.