S06c is a Russian station that uses the same voice generator as S06.

S06c repeats a single 5-digit group - which always begins with "11" - for 4 minutes. Each broadcast consists of two transmissions spaced ten minutes apart, with the latter being 1-3 MHz lower or higher in frequency. All broadcasts are unscheduled.

The exact purpose of S06c is unclear. Judging by the time and frequency usage, the groups between 11001 and 11216 might be the diplomatic network addresses, while the others might be domestic targets.