Klub Niezwykłych Łączności
On 1 December 1924 the SAQ station SAQ has started handling commercial telegraph traffic. On 1 December 2024 a message was sent commemorating the 100 years anniversary.
Reception at Marcin SQ2BXI (Gdańsk/Poland):
Reception at Jacek SQ5BPF (Warsaw/Poland):
Continue reading “SAQ centennial transmission on 1 December 2024”
The VLF radiostation on Grimeton/Sweden with the callsign SAQ was put into commecrial service on 1 December 1924. SAQ was a transatlantic station. The main correspondent were stations in Long Island, New York, USA.
SAQ was one of the Alexanderson system stations built under the supervision of the Radio Corporation of America (RCA) . These stations were similar to each other, the antenna and transmitter (an Alexanderson alternator) were the invention of Ernst Alexanderson. Poland had a similar station in Babice near Warsaw with the callsigns AXO/AXL/SPL.
On 1 December 2024 there will be a transmission to commemorate the 100 years of SAQ being put into commercial service. The message will be transmitted on 17.2kHz CW (morse code).
SCHEDULE:
10:20 CET (09:20 UTC) Live YouTube broadcast begins.
10:30 CET (09:30 UTC) Start-up of the Alternator.
11:00 CET (10:00 UTC) Transmission of a message*
The event will be streamed live on youtube under the link: https://www.youtube.com/watch?v=VwINhKcSF5o
Usually about 10 minutes before the transmission of the message “VVV DE SAQ” is transmitted continiously.
A video of the SAQ transmission on 20221116 16:00 UTC, commemorating the 50-th Anniversary of the UNESCO World Heritage Convention.
Received at SQ5BPF QTH Warsaw/Poland KO02md.
E-field active antenna, vlfrx-tools and Spectrum Lab receiver
The transmitted message is:
In previous articles i’ve shown some typical ZEVS messages , and an analysis of the amount of messages per day .
This repository has all of the scripts used during the analysis: https://github.com/sq5bpf/zevs-analysis
So what more could we get out of the opublished ZEVS dataset ?
In the last article i’ve written about a method of automatically finding ZEVS trasmissions, and an analysis of it’s messages: Analysis of ZEVS messages
Luckiny i have data from 25 August 2021 until now. Using it i can check if anything has changed during the Russian invasion of Ukraine in 2022.
These are encrypted military messages. So there is no reason to analyze them, right? 🙂
Continue reading “An analysis of ZEVS messages during the russian invasion in Ukraine in 2022”
Russia uses radiocommunications in the ELF band to send messages to it’s nuclear submarine fleet. This transmitter it called ZEVS, the frequency is 82Hz (yes: hertz, not kilohertz, not megahertz). For more info see here: http://www.vlf.it/zevs/zevs.htm
I’ve installed a grabber on the KLUBNL.PL page showing the spectrum around 82Hz. It is available here: https://klubnl.pl/wpr/index.php/klubnl-pl-grabbers/grabber-zevs-82hz/
This grabber calculates the spectrum in 80-84Hz every 60 seconds, and makes spectrograms out of it. The files with the spectrum information are not deleted, so out out of coincidence i have a history of data from 25 August 2021 until now (around 10 June 2022).
And since i have this data, it would be nice to do an analysis how the messages to the submarine fleet look like, and how often are they transmitted.
We have published data from observations of the ELF spectrum 80-84Hz (ZEVS) over a period of a few months.
The data is avaliable here: https://klubnl.pl/zevs/
Christmas transmission from SAQ on 17.2kHz, 24 December 2021 8:00 UTC
Received at SQ5BPF QTH Warsaw/Poland KO02md.
E-field active antenna, vlfrx-tools and Spectrum Lab receiver.
On the recording one can see a weak carrier between the symbols. This is because the keying circuit leaks a weak carrier. The leakage is about 2kW.
QTH Jacek / SQ5BPF Warsaw KO02md
The message was:
THIS IS GRIMETON RADIO STATION/SAQ IN A TRANSMISSION USING THE ALEXANDERSON 200KW ALTERNATOR ON 17.2KHZ. = WE WISH YOU ALL A MERRY CHRISTMAS AND A HAPPY NEW YEAR. = SIGNED WORLD HERITAGE GRIMETON RADIO STATION AND THE ALEXANDER GRIMETON FRIENDSHIP ASSOCIATION.= FOR QSL INFO PLEASE READ OUR WEBSITE ALEXANDER.N.SE. DE SAQ SAQ SK
After a long period of inactivity the RSDN stations are active again. Right now (12 october 2021) three frequencies are active: 11.9kHz, 12.65kHz, 14.88kHz.
This is a hyperbolic navigation system, which broadcasts a periodic carrier. More information is avaliable here: http://www.vlf.it/alphatrond/alpha.htm
For people interested in VLF this is a great test signal, whch can be used to check receiving equipment.
RSDN 2021
In 2019 i’ve written that the SQ5BPF grabbers will be temporarily offline and should return in winter 2019. Unfortunately this “moment” got extended to august 2021.
Now, finally, I’m trying to reactivate them, The VLF antenna has been installed again. For now I’ve activated the ZEVS 82Hz and VLF 8270Hz grabbers. Because of changes in vlfrx-tools noiseblanker from versions 0.6 to 0.9, i will be trying to find the parameters for best reception, so please stay tuned, the grabbers might not be operating at their best right now.
The rest of the grabbers will be activated shortly.
As before, i’m recording the while 0-24kHz bandwidth, and keeping the recordings for a few days. They can be provided to interested parties upon request (for scientific reasons etc).