priyom.org

M12

Enigma ID M12

Name
Frequencies
Status Active
Voice N/A
Emission mode ICW
Location Moscow, Russia; Khabarovsk, Russia
Activity pages

Download audio sample

Known counterpart stations E07, G07, S07, V07, XP, XPA, XPA2, XPB, XPH

M12 is the Morse code flavor of the Russian 7 operator.

Null format:

911 911 911 000
3-digit schedule ID  
Repeated for 2 minutes

Traffic format, single message:

Intro Preamble Message Outro
903 903 903 1 8603 63 27073 15164 79261 ... 48334 000 000
3-digit schedule ID Message count 3- or 4-digit group Group count 5-figure single groups  
Repeated for 2 minutes Repeated twice    

Traffic format, two or more messages:

Intro Preamble Message Interlude Preamble Message Outro
124 124 124 2 4582 132 67540 37492 ... 19241 81259 124 124 124 2 8248 112 94213 70216 ... 03679 52901 000 000
3-digit schedule ID Message count 3- or 4-digit group Group count 5-digit single groups 3-digit schedule ID Message count 3- or 4-digit group Group count 5-digit single groups  
Repeated for 2 minutes Repeated twice   Repeated for 1 minute Repeated twice    
For the first message For each further message  

The intro, the interlude, and the outro are sent at a slower speed than the rest of the transmission: 75 ms per unit. There are several speeds available for the preamble and the message: 60, 50, or 43.75 ms per unit; the speed is fixed on a per schedule basis. Zero is sent as "T" - a single dash.

In case of an unexpected interruption during the transmission, the station restarts with the intro, repeated for one minute, followed by the current message continued from some groups before the failure; the preamble is omitted.

The standard M12 schedules are twice weekly, and consist of three transmissions spaced twenty minutes apart. Each successive transmission is 1-2 MHz lower or higher in frequency. The third transmission doesn't take place in case of a null message. The frequencies usually change monthly.