|Name||Russian Man "Control"|
|Frequencies||Various (Mainly 13883)|
|Voice||Male, automated (the same as S06)|
|Emission mode||USB + carrier|
|Known counterpart stations|
S25 is run by Russian Main Intelligence Directorate (GRU).
The standard a format is given below. The outro is sometimes preceded by a quintuple group repeated for several minutes.
|Section #1||Section #2||Outro|
|3-figure ID||5-figure group, purpose unknown||3-figure ID||5-figure group, purpose unknown|
|Repeated for 4 minutes||Repeated for 4 minutes|
Nowadays S25 runs only one consistent schedule, which transmits at half hour. Both sections are sent on the same frequency, and then the transmission is repeated 10 minutes after the start of the first transmission on a different, random frequency. The transmission is also repeated two days later on the same times and frequencies.
In the 1990s S25 had a daily schedule at 08:00 UTC, for the first 20 minutes on 14890kHz, then for the remaining 20 minutes on 11270kHz. Each transmission had four sections, repeated for 10 minutes each. The ID was always 615. The ending was "615 615 615 000". In 1998, its operation was changed to weekly on Monday only, then disappeared completely in 1999.
In September 2004, the current format was introduced. S25 can have years long breaks in operation - it was unheard in 2004-2007, 2007-2012, 2012-2014, 2014-2016.
In 2017, S25 revived with a new weekly schedule and frequencies (see schedule).