Thales Système 3000 Voice Scrambler
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Thales Système 3000 HF Modem - Système 3000, Skyhopper Mode - Système 3000, Voice Scrambler Mode
Voice Scrambling mode from Thales Système 3000 HF Modem. Has characteristic PSKPhase-Shift Keying and MFSKMultiple Frequency Shift-Keying bursts at the beginning and end of a voice transmission. The Système 3000 is used in the TRC-3600 transceiver produced by Thales in France.
The PSKPhase-Shift Keying preamble lasts 150ms, and the PSKPhase-Shift Keying end of transmission burst lasts 100ms. In between the bursts, there is a very brief MFSKMultiple Frequency Shift-Keying burst right after the preamble, and right before the end of transmission PSKPhase-Shift Keying burst. The MFSKMultiple Frequency Shift-Keying is likely 8-MFSKMultiple Frequency Shift-Keying.