I have developmental authorization for 15.8 kHz, which is right at the best
spot.
This frequency range was used for the horizontal for the old CRT TV sets. These
are mostly gone now.
I would think it would be easier to get authorization in this range.
Most of the VLF station for Navy have moved up above 19 kHz where the antennas
are more efficient.
73
John VA3VVV
--------------------------------------------
On Mon, 12/11/17, VIGILANT Luis Fernández <[email protected]> wrote:
Subject: RE: VLF: Transatlantic success East to West
To: "[email protected]" <[email protected]>
Received: Monday, December 11, 2017, 3:43 AM
#yiv1686070705
#yiv1686070705 --
_filtered #yiv1686070705 {font-family:Wingdings;panose-1:5
0 0 0 0 0 0 0 0 0;}
_filtered #yiv1686070705 {panose-1:2 4 5 3 5 4 6 3 2 4;}
_filtered #yiv1686070705 {font-family:Calibri;panose-1:2 15
5 2 2 2 4 3 2 4;}
#yiv1686070705
#yiv1686070705 p.yiv1686070705MsoNormal, #yiv1686070705
li.yiv1686070705MsoNormal, #yiv1686070705
div.yiv1686070705MsoNormal
{margin:0cm;margin-bottom:.0001pt;font-size:12.0pt;}
#yiv1686070705 a:link, #yiv1686070705
span.yiv1686070705MsoHyperlink
{color:blue;text-decoration:underline;}
#yiv1686070705 a:visited, #yiv1686070705
span.yiv1686070705MsoHyperlinkFollowed
{color:purple;text-decoration:underline;}
#yiv1686070705 span.yiv1686070705EstiloCorreo17
{color:#1F497D;}
#yiv1686070705 .yiv1686070705MsoChpDefault
{}
_filtered #yiv1686070705 {margin:70.85pt 3.0cm 70.85pt
3.0cm;}
#yiv1686070705 div.yiv1686070705WordSection1
{}
#yiv1686070705
Fantastic job! Congratulations to
all
J
Does it confirms the graphic
already distributed in this list showing that the best bands
for long distance
should be around 15KHz ? (see
attached)
If so. A 17KHz allocation would be
really interesting. But this will probably take a big
burocratic effort with local
PTT
Or not so hard? ….. who knows.
Worth a try ;-)
73 de Luis
EA5DOM
De:
[email protected]
[mailto:[email protected]]
En nombre de Markus Vester
Enviado el: domingo, 10 de diciembre de 2017 22:05
Para: [email protected]
Asunto: Re: VLF: Transatlantic success East to
West
Congratulations, great work by
Mike, Stefan and Paul! I'm glad to see this happen.
Best 73,
Markus
PS: Secretly in my heart I'm hoping that one fine day we
might receive a 17 kHz amateur allocation...
-----Ursprüngliche Mitteilung-----
Von: Paul Nicholson <[email protected]>
An: rsgb_lf_group <[email protected]>
Cc: Michael Smith <[email protected]>
Verschickt: So, 10. Dez 2017 16:26
Betreff: VLF: Transatlantic success East to West
Stefan wrote:
> f = 17470.1000 Hz
> Start time: 07.Dec.2017 21:30:00 UTC
> Symbol period: 60 s
> Characters: 1
> CRC bits: 10
> Coding 16K21A
and
> I transmitted the message last night again [9th]
A good signal at Forest, VA, from the overnight
transmission
9th/10th, via Mike Smith's VLF receiver at
37.35348N,79.19450W,
near Lynchburg.
Decoded 'T' with Eb/N0 = +1.5 dB, BER 42.5%, rank
9;
S/N was -36.29 dB in 1Hz;
Reference phase 120,135,120,135;
Congratulations to Stefan DK7FC and Mike KE4RJQ for the
first VLF east-to-west transatlantic message. Distance
is 6817.7 km.
This is a most significant achievement. East to west is
some
20dB harder than the other direction!
You can run the decode yourself from the 'vt' file
at
http://abelian.org/vlf/dk7fc.171209f4.vt
The file is 4.2 Mbyte, 2 I/Q sample pairs/second.
It was extracted from Mike's raw recording with
vtread -T2017-12-09_21:30,+34590 /data/raw-fb |
vtfilter -h bp,f=17470,w=3000 -h bs,f=16400,w=600 -h
bs,f=18300,w=800 |
vtblank -a13 -d0 -t100 -v | vtmult -f 17470.1 |
vtresample -r480 |
vtresample -r2 > dk7fc.171209f4.vt
Decode with:
vtraw -oa dk7fc.171209f4.vt |
ebnaut -dp16K21A -r2 -S60 -k10 -N1 -PS15 -L800 -v -c8
-a50
This was a clean decode with no false detects to get in
the
way. The signal is extremely weak but gives an
unambiguous
decode.
Please CC Mike in any replies, as he is not on the RSGB
mailing list.
--
Paul Nicholson
--
|
