A procedure for obtaining a reduced complexity signal space detector is proposed and applied to the EEPR4 channel combined with d = 1 code. For the channel considered, the signal space detector requires at least 10 observation samples to attain the same minimum distance as the Viterbi algorithm (VA). The resulting signal space detector can be implemented with 7 linear discriminant functions, 10 threshold detectors, and a Boolean logic function. All coefficients of these linear functions are from {0, +/-1, +/-2}.