odd wideband signals spotted recently on 9110 KHz (center frequency) and likely related to Russian tests or exercises. Transmissions (Figure 1) consist of a 3xFSK 250bd/500 waveform which occurs as stand-alone transmission or as preceding a wideband PSK waveform, the latter also heard as stand-alone. The FSK signals are 1500 Hz spaced, carry encrypted streams and occupy a 4KHz bandwidth. PSK signals exhibit a clear component in the fourth power (Figure 2) that leads to think to a QAM waveform either 5000Bd/5KHz bandwidth and 10000Bd/10KHz bandwidth. Further analysis of the IQ samples, or just further recordings, are needed to shed some light on the modulation.
Besides the two (new?) waveforms, the most surprising thing was hearing a short track of the Russian version of "Winnie Pooh" cartoon transmitted in DSB mode in between FSK and PSK (Figure 3): strange but true, check by yourself
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| Fig. 1 |
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| Fig. 2 |
- on-air track https://yadi.sk/d/Q5hgfayn2DLOCw
- Russian cartoon track https://t.co/il9bFkhOyQ
(at first I had mistaken its waterfall pattern as a sort of vocoder, my friend KarapuZ immediately identified it as a Winnie Pooh cartoon track).
A topic was opened by KarapuZ on radioscanner ("ansanto" is my nickname there):
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| Fig. 3 |
3xFSK-250Bd-500 https://yadi.sk/d/jIQoNb0aNCX_HA
10 KHz wideband PSK https://yadi.sk/d/xb1y3yTkKvPm_Q
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