50Bd/250 FSK is another waveform used by CIS Navy for their fleet broadcast. Unlike the same waveform but with 136-bit framing (T-600 136), this one shows all the characteristics of the (perhaps more) well known 50Bd /200 broadcast, ie:
* 44 bit sequence (usually "11100001010010111110000101001101011010101101")
* 70-bit Initialization Vector (ten 7-bit words, repeated twice)
* payload arranged in the 4:3 ratio
* 7-bit words "000100" as EOM
