It seems that the CIS MFSK-68 protocol is constantly being modified and added new modulations. The "standard" waveform consists of 68 tones (2 x 34) 47 Hz spaced, each 1 second are sent 10Khz-wide PSK-8 9000Bd bursts (2 symbol element periods length) possibly acting as sync. Unlike normal MFSK (1 symbol = 1 tone) the signal uses 5-tones symbols so that its manipulation speed sums to 47Bd: 45 MFSK symbols + 2 PSK symbols.
On March 28th, at 1255 UTC, the signal has been heard on 14681.0 KHz/USB with an interesting variant consisting of "slots" with two tones, about 540 Hz and 2230 Hz, with QPSK modulation and speed 47 symbols/sec. The QPSK tones are transmitted at a lower level than the MFSK tones.
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Don't know if these are test or sperimental transmissions, it is worth noting the constancy of the speed (47 Baud) and the reductions of tones during the 2-tones QPSK slots. Maybe further recordings of such wavforms could help.
