Enigma ID M42 (catch-all MFA Moscow designator)

Name Perelivt
Status Active
Voice N/A
Emission mode 8PSK, 3000 Bd; 66-tone MFSK, 46.875 Bd, 46.875 Hz + 8PSK, 9000 Bd; 128-tone OFDM, 20.(979020) Bd, 23.4375 Hz; 128-tone OFDM, 41.(958041) Bd, 46.875 Hz
Location Worldwide
Activity pages

Known counterpart stations

Perelivt[a] is a proprietary full duplex HF communication system, used exclusively by the Russian diplomatic service.

To establish a link, Perelivt automatically scans 3 channels in succession, emitting bursts of the 3000 Bd 8PSK waveform while simultaneously awaiting the other station's response; in case none is heard, the next channel is tried instead. Once a link is established, the system uses one of three different waveforms: MFSK, narrowband OFDM, or wideband OFDM.

Perelivt was introduced on the Russian diplomatic links around 2014, gradually replacing the previously used Serdolik through 2019.


Despite the ~3 kHz bandwidth of most waveforms, the emission mode is not USB on a -2 kHz offset. The signal is formed around the center frequency, occupying between 1.5 and 5.1 kHz on each side; the spectrograms provided here are to scale.

Mode Spectrogram Sample
3000 Bd 8PSK

66-tone MFSK

128-tone OFDM (narrow)

128-tone OFDM (wide)


  1. Perelivt is a code name created by Priyom to unambiguously refer to all four waveforms as part of a single system. Like "serdolik" (сердолик), "perelivt" (переливт) is a cryptocrystalline mineral. The actual name of the system is unknown.