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E06 is operated by the Russian Main Intelligence Directorate
(GRU). For the current times and frequencies, refer to our Number Station
Null format: (rarely heard as of August 2014)
If more than one message is to be transmitted, then instead of
"00000", the transmission ID is spoken again for one minute, then
the standard message procedure follows for the next message.
E06 has two rare variants: E06a, referring to
2-group messages commencing with "11111", and E06b, referring to
additional 5-figure group in the preamble.
Even though E06 operates regular schedules, the amount of them
is low. As of August 2014, only four regular non-training
transmissions are being noted. Vast majority of the transmissions
are unscheduled, and are usually related to current political
events involving Russia. Sometimes the transmissions appear to
operate on a daily schedule, but cease within a few days. Most
recent such surge in activity was observed in February and March
2014, during the events in the Crimea.
The transmissions are handled in two ways: either automatically,
or manually. On the former, a test is made approximately 15 minutes
before the start of the actual transmission, and consists of a long
1 kHz tone, and the E06 voice speaking the upcoming ID once. The
transmissions themselves start exactly on time. On the latter,
manual test count in the format "01234 01234 01234..." is made
roughly an hour before. The manual transmissions frequently start
late, and the voice is sometimes distorted.
The transmissions, even unscheduled ones, are usually repeated
an hour later on an either lower or higher frequency, and usually
the next day at the same times and frequencies as well. Oddities to
this are sometimes observed; for example, from May 2014 onwards, a
schedule heard only on second and fourth Wednesday is being
observed with the primary transmission at 11:30 UTC, and the repeat
at 16:00 UTC, 5.5 hours later, with no additional repeat the next
The entire transmission process is handled using a computer
running Windows 7, as evidenced by leaked sound effects. Prior to
April 2014, Windows XP was used instead. The upgrade is probably
related to end of support of this operating system by
On regular schedules, the frequencies and the transmission ID
are changed either monthly or seasonally, and usually re-used on a
yearly basis. The frequencies being used on both regular and
irregular schedules indicate worldwide operation.
The E06 messages don't exhibit any non-randomness, so it's
likely one-time pad being used as the encryption method.
Interestingly, putting the transmission ID, the unknown-purpose
3-figure group and the message length together in a string
frequently gives one where not a single digit is repeated.
Null messages on E06 are rare. These, however, can be heard four
times in a month on a schedule that operates on second Wednesday at
19:20 and 20:20 UTC, and the following Sunday at 11:20 and 12:20
UTC. This schedule was first noted in August 2010, but has never
sent a full message as of August 2014.
Two schedules, on first and third Thursday at 20:30 UTC, and the
Fridays following the first and third Thursday at 21:30
UTC, are handled entirely differently to the normal transmissions.
The messages are non-random, the message length is fixed at 20
groups, and the messages are repeated for many months. While the
transmissions use the same software as the regular transmissions
for producing the numbers, the transmissions are started up
manually, frequently late. All of these behaviors together suggest
a training nature of these broadcasts.
Up until November 2013, the training messages were 15 groups
long. This change was also made on the training schedules of E06's
Up until April 2014, even the numbers being spoken were produced
manually, presumably by an operator at a keyboard, as indicated by
highly inconsistent tempo. The zeroes ending the transmissions were
always noticeably spaced.
It is unknown when E06 was first noted, but it was going strong
by the 1970s. Its operation habits, besides equipment upgrades,
have not changed since then.
E06 has been occasionally noted with extremely long messages,
for example a 517-group message on 24 November 2000, and a
325-group message on 29 November 2005.
Many different voices have been used throughout E06's existence,
sometimes only lasting a few days. The current one is in use since
February 2001, but dates back to at least 1992, and was previously
used by E07.
While initially reported using the full AM mode with two
sidebands (A3E), E06 changed to the current USB + carrier mode
(H3E) some time in late 1990s. On 11 June 2014, E06 was noted
sending in pure USB mode without carrier (J3E), but has not been
seen in this mode ever since.
voice 2: 821 (R5) * 704 704 42 42 = (42 pairs) 60083 53821 53933
.....23301 62657 31341 30833 14423 94069
88315 7630530346 63164 22476 13677 41846 36111 .... 10496 * 704
704 42 42 00000
voice 1: 341 (R5) * 269 269 37 37 = (37 pairs) 19881..... ending
as E6 voice 2
voice 3: pairs .....95978 03685 20719 16727.... format as E6 voice
null message format (voice 2): 897 897 897 00000 (R5)
Russian Intelligence. R 12/03/92
Tcp d2 17 english man irdial by The Conet
Russian Intelligence. Different voice. R 12/08/93
Tcp d2 23 english man irdial by The Conet
English Man Version 1
See Enigma signal list.
Tcp d3 05 english man version 1 irdial by The Conet
English Man Version 3
Note the 'zeeero'.
Tcp d3 06 english man version 3 irdial by The Conet
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