We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissable in your locale.

Author Topic: The Siren or Alarm sound at 4770KHz  (Read 436 times)

Offline Perseus68

  • Newbie
  • *
  • Posts: 1
  • Karma: +2/-0
    • View Profile
The Siren or Alarm sound at 4770KHz
« on: December 06, 2020, 2200 UTC »
Quite well audible those nights, at least from my QTH (canary islands).
It was already known from the SDR of Twente (The Netherlads)
I grabbed a couple of videos just in case your are interested.

https://youtu.be/o1le0EfnDjI

https://youtu.be/TDJBvGg7pto

Gear: SDRPlay-RSP1 + SDRUno + Home-made 1m diameter active Loop

Offline Teotwaki

  • DX Legend
  • ******
  • Posts: 2261
  • Karma: +22/-1
  • California
    • View Profile
    • My adventures are at Sun To The North
Re: The Siren or Alarm sound at 4770KHz
« Reply #1 on: December 19, 2020, 0239 UTC »
Thanks for recording that! It is very fascinating!
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Offline jasmine

  • Full Member
  • ***
  • Posts: 158
  • Karma: +16/-1
  • Seattle
  • Riding the (electromagnetic) waves...
    • View Profile
Re: The Siren or Alarm sound at 4770KHz
« Reply #2 on: January 08, 2021, 1250 UTC »
Quite well audible those nights, at least from my QTH (canary islands).
It was already known from the SDR of Twente (The Netherlads)
I grabbed a couple of videos just in case your are interested.

https://youtu.be/o1le0EfnDjI

https://youtu.be/TDJBvGg7pto

Gear: SDRPlay-RSP1 + SDRUno + Home-made 1m diameter active Loop

This is "The Alarm"

Thought to be used by the Russian Army Western Military District:  https://priyom.org/military-stations/russia

More info here: https://priyom.org/military-stations/russia/the-alarm
« Last Edit: January 08, 2021, 1252 UTC by jasmine »
SDRPlay RSP1a, Airspy HF+Discovery & MLA-30 Magnetic Loop Antenna