Unid MFSK-13 system running at different speeds (31/62.5/125 Baud) and intervals (125/250 Hz) spotted on Twente WebSDR on ~10625, ~9091, ~7779 KHz/USB thanks to friend radiotehnikaT101.
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| Fig. 1 |
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| Fig. 2 |
It's to be noticed the quick change of the waveform in the 10625 KHz recording (from 31Bd/250 to 125Bd/126): maybe the first part could be the "call" segment. I tried a rough demodulation by replacing the Hex characters (0...C) with their binary value (0000...1100) but I didn't find anything interesting in the bitstreams except some patterns in the 31Bd/250 segment (88/176 bit period).
Most likely these are experimental transmissions in the network of the Ministry of Foreign Affairs of the Russian Federation.
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| Fig. 3 |
https://yadi.sk/d/ShwOzo4-qA6Ygg
https://yadi.sk/d/oAWEbU54GvHljQ