Re: VLF: 24.1 and 25.0 kHz - China?

[Markus Vester <markusvester@aol.com>]

Thanks Marcus for sharing this observation. According to recent posts from Jean-Louis Rault and David Wilson to the VLF Group, the transmitter is actually located near Mokpo / South Korea:
https://groups.yahoo.com/neo/groups/VLF_Group/conversations/messages/25188
https://groups.yahoo.com/neo/groups/VLF_Group/conversations/messages/25189

The 25 kHz trace is visible around the clock on my VLF colour-DF spectrogram:
http://www.df6nm.de/vlf/vlfgrabber.htm.

All the best,
Markus.(DF6NM)

-----Ursprüngliche Mitteilung-----
Von: Marcus PY3CRX PY2PLL <py2pll@py.qsl.br>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Di, 19 Jul 2016 4:54 pm
Betreff: Re: VLF: 24.1 and 25.0 kHz - China?

Hi Markus

 

I don’t have how to RDF but I recorded this today at 14Z (I’m 23 south / 46 west).

 

Does not looks like Beta from Russia (was not detected at Twentee Netherlands SDR).

 

There’s a 2 minute video of the time window 13:57 ... 14:01. I have a bigger HDSDR IF file recorded (from 13:55 to 14:10 I guess).

 

The video: https://youtu.be/kdcvMCUp_uU

 

73

Marcus

PY3CRX/PY2PLL

GG66rf

 

From: Markus Vester

Sent: Monday, July 11, 2016 7:15 AM

To: rsgb_lf_group@blacksheep.org ; vlf_group@yahoogroups.com

Subject: VLF: 24.1 and 25.0 kHz - China?

 

Since July 1st, I am observing a continuous emission on 25.0 kHz, cochannel with the well-known occasional Russian time signals:
http://www.df6nm.darc.de/vlf/vlfgrabber.htm
The signal consists of a continuous idle pattern with 25 Hz spaced lines, apparently interrupted every hour by data transmissions of variable duration. During earlier months, the same signal was sometimes visible on 24.1 kHz, just above NAA. Searching the web brings up hints of a Chinese transmitter on that frequency, matching the RDF azimuth (approx. 65°) and diurnal fades (~ 13 and 1 UT) observed here. Does anyone happen to have further info regarding TX location or radiated power?

All the best,
Markus (DF6NM)