Re: VLF: Pacific MSKs in Europe

[Markus Vester <markusvester@aol.com>]

 

Peter, thanks for the comment! Yes the Indian VTX is clearly here, and stronger at the 4X1RF grabber. The spectrum seems to have some regular structure, so probably different modulation or pseudorandom encryption parameters.

 

I'm currently using the LF transmit antenna, a top-loaded vertical 10 m above the roof. VLF is extracted across a 33 nF capacitor in the ground line, and fed through a simple bipolar preamp to a cheap USB soundcard.

 

BTW It's funny how quickly my remaining wish came true: GQD went off between 10 and 12 today, and indeed there's a very weak hump from Japan at 22.2 kHz (see attached, colours swapped for better visibility). The peak is also present on Paul Nicholson's plot.

 

Best wishes,
MArkus (DF6NM)

_________________________________________
Von: pws <pws@legal-medicine.de>
An: rsgb_lf_group@blacksheep.org
Verschickt: Di., 11. Jan. 2011, 13:19
Thema: Re: VLF: Pacific MSKs in Europe

 

Hi Markus,

 

Not bad! Watch 19.2 kHz. Clear visible sunrise effect around 0100 utc.
Should be one of the VTX-frequencies:
http://maps.google.de/maps?ll=8.3845691,77.754468&z=14

 

Would be interesting what you can "see" up to ~85 kHz and what kind of
antenna/preamp used.

 

Greetings from Kiel,

Peter
_________________________________________
VLF: Pacific MSKs in Europe

 

The wideband panel at http://www.mydarc.de/df6nm/vlf/vlfgrabber.htm is currently set to the military frequencies above 19 kHz.

 

In addition to NWC (Australia), which has been regularly visible here on 19.8 kHz above GBZ, I noticed that there is also a weak strip and corresponding hump on 21.4 kHz from NPM (Hawaii). It seems to be best in the morning hours, especially during the dips of its overwhelming neighbour HWU 21.75 kHz. It's very strong at KL7UK's grabber and also a clear peak on http://abelian.org/vlf/spectrum.shtml in Todmorden.

 

NAA 24.0 kHz is often remarkably strong on the samplerate edge,  and at times there is even a weak trace on 22.8 which seems to be an alias of NML 25.2 kHz.

 

NDT (Japan 22.2 kHz) has so far escaped my detection attempts, but it may be too difficult due to the proximity of GQD.

 

Best 73,
Markus (DF6NM)

df6nm_vlfwide_110111_1200_NPM_NDT_swappedcolours.jpg
Description: image/pjpeg

paulnicholson_spec2b_110111_1144_NPM_NDT_NLM.png
Description: PNG image