The Wideband Forward Error Correction (FEC) Decoder (WFECDEC) implements a hard decision threshold decoder with syndrome feedback for the r=7/8, J=6, Na = 1176 self orthogonal systematic convolutional code. ECL I data, Q data, and baud rate clock are inputs from the demodulator. The decoder eliminates differential coding by resolving all lock-up ambiguities of the demodulator. The decoder outputs the corrected ECL information rate data stream and clock. A 3.55 dB coding gain and a 4.6 dB total gain (coding gain, elimination of differential coding, and shift of modem operating point) are being realized on a 280 Mb/s information rate and 320 Mb/s OQPSK transmission rate link. Implementation allows much higher data rates. Rate 1/2 soft decision Viterbi decoding has been provided in various demodulators.