CIS36 50

This mode can be found all over the HF bands. It is believed to be a Russian Naval mode which transmits FSK (Frequency Shift Keying) at a data rate of 50 baud with a 200 Hz shift and is sometimes known as BEE. Some stations transmitting this mode transmit constantly sending idles between messages while others only transmit when a message is due at fixed intervals. All the CIS36-50 transmissions decoded so far have been encrypted and look like this ..

13:19:29 Message Start
Sync 0x1414bebe64c
Session Key is 0x18 0x5 0x1f 0x16 0x4 0x9 0x8 0x1 0x4 0x10
ZHGANENXGWJBAQEYEXRGBZEN
End of Message (44 characters in this message 0 of these contained errors)

Rivet can decode CIS36-50 transmissions live from a HF radio (in USB mode) via the line in input on your computers soundcard or from a pre-recorded WAV (mono and 8000 Hz sample rate only). Rivet calibrates itself from the alternating idling sequence that precedes a CIS36-50 message then looks for a valid sync word and session key before decoding and displaying a message.

Note that on the LF bands CIS36-50 is transmitted at a speed of 36 baud but at the moment Rivet can't decode this only the 50 baud transmissions.

There is a WAV file recording of a 50 baud CIS36-50 signal on the Rivet sound samples page here.