|Name||D marker, Fazan-37|
|Location||near Saint Petersburg, Russia
|Known counterpart stations|
"The D Marker" is a Russian military commandment network. It broadcasts on 3240 kHz around the clock. It occasionally sends "Monolith" type messages addressed to Fazan-37 (Russian: Фазан-37). Multilateration attempts seem to point towards the Saint Petersburg area, which would imply that it is part of the Western Military District.
The first frequency known to be used by this network was 5292 kHz. The first known message on this frequency was heard on November 12, 2011. This network had no channel marker until February 11, 2015. The first channel marker was a long dash followed by two short tones (like the Morse code character "D"), sometimes with yet another short tone appended (Morse code character "B"). This marker has proven itself to be unstable, being sometimes heard with 7 or 8 short tones. On June 5, 2017, it changed its frequency from 5292 kHz to 3240 kHz. On October 3, 2018, it was noticed that the D marker had started being receivable on 6480 kHz, a harmonic of 3240 kHz, which often offered much stronger reception; this harmonic disappeared on November 5.