A Russian military station, nicknamed by radio hobbyists "The Buzzer," is an HF station that broadcasts on a frequency of 4625.0 kHz. First reported in the 1970s, the station transmits using AM with a suppressed lower sideband (USB modulation), but it has also used full double-sideband AM. The signal consists of a short, monotonous buzzer-sounding tone that repeats at a rate of approximately 21 to 30 plus tones per minute, 24 hours per day.
Nicknamed “The Pip,” by radio listeners, this Russian military station broadcasts on 5448.0 kHz (day), and 3756.0 kHz (night). It broadcasts continuous short, repeated beeps at a rate of around 50 per minute. Like the Buzzer described above, the beep signal is occasionally interrupted by voice messages in Russian sent by both male and female announcers. The Pip has been active since around 1985 when its distinctive beeping sound was first recorded by listeners. The station's format resembles, in many ways, that of its presumed sister station “The Buzzer.”
The third of our mysterious Russian military stations are known as “The Squeaky Wheel,” another nickname given by the radio hobby community. From around 2000 until 2008 the station's attention tone was a high-pitched two-tone signal that vaguely resembled a squeaky wheel. From 2008 the channel marker changed to two different tones in a short sequence repeated with a short silent gap. This station transmits voice on 3828.0 kHz (nights) with CW on 3895.0 kHz, and 5473.0 kHz (day) voice with CW on 5361.0 kHz.
Several in our radio hobby believe that the HF radio presence of these Russian Ground Forces consists of many interconnected subnetworks and that the ones I have discussed here are just three of them.
In 1978 Harry and several others noted a CW station sending the letter "W" continuously on 3584.0 kHz, in the 80-meter ham band. There was indirect evidence using greyline propagation techniques that this transmitter was in Cuba. He theorized that it may have had something to do with the Russian/Cuban military services. This started a chain of events that elevated the attention of the radio monitoring community to this “W’ CW station and to other CW beacons in the HF spectrum like it.
This group of radio markers with single-letter identifiers (C, D, M, S, P, A, M and K) have been regularly reported centered on 3594.0, 4558.0, 5154.0, 7039.0, 8495.0, 10872.0, 13528.0, 16332.0 and 20048.0 kHz. The term "cluster markers (beacons)" is frequently used for them, as they transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard Morse code and are located at Russian Naval Bases.