Re: LF: LF and VLF EbNaut

[Domenico IZ7SLZ <iz7slz.domenico@gmail.com>]

LF,

EbNaut decodes of both NA stations of last two days in JN80nu (Apulia - South Italy)  are listed on the log:

https://www.qsl.net/iz7slz/EBNAUT/DECODED.TXT

Traces of VO1NA's signal are visibile also on the opds waterfall: 

https://www.qsl.net/iz7slz/OPDS/opds.jpg

Thanks to Joe and Rob for putting on air a very good signal, and i hope that some other operators have tryed to receive and decode the signal.

Receiving setup is really not too complicated and i invited all LF operators to try the reception.  Here some informations on the hardware and software setup used at iz7slz:

- a whip antenna (ex Furuno Navtex preampl. model NX-500) feeds both JRC NRD-92 receivers (i call them 'twins') using an antenna splitter. One receiver is for LF, the other works on MF;

- a GPS referenced oscillator (EPSILON CLOCK) gives 10 MHz to both receivers,

- a second U-Blox Neo8 GPS gives precise UTC time reference to the Ubuntu PC and also 1pps signal to the sound card of the same pc

- The following great vlfrx-tools (thanks Paul Nicholson !)  are used on this ubuntu pc

           'vtcard' manages the sound card

           'vttime' does the samplerate calibration and timestamp of the samples

           'vtwrite' records on the storage hard disk the audio captured from the two receivers;

- the linux programs used to syncronize the PC clock with UTC are 'gpsd' and  'chronyc'. The Neo8 GPS is connected at pc serial COM1;

- The bash program 'autodecoder' uses 'vtread' to bring from the storage the raw data and attempts the decode using 'ebnaut' linux version.

  The excellent noise blanker 'vtblank' is used in auto-decoder program. Without this NB almost 90% of the decodes would be lost.

I have uploaded a folder with some pictures of the hardware setup. There is also latest version of 'autoebnaut' linux bash program :

https://drive.google.com/file/d/1iDuIwgfH3wnDRUIPOXJvI9fEsFBluC2R/view?usp=sharing

Any helps, suggestions and comments on this program are welcome.

I'm at disposal for any assistance, hoping to increase numbers of receivers also on the other side of the pond.

73, Domenico IZ7SLZ

 

On Sun, 9 Dec 2018 at 17:30, Markus Vester <markusvester@aol.com> wrote:

Here's a summary of decodes from here last night. On average, SNR was significantly better than during the previous night. Unfortunately I had forgotten to activate data saves at DL0AO so these are missing.

EbNaut Decodes 2018-12-08/09

VO1NA 137477 Hz:
        DF6NM
start  sym  car  message
22:00 15.4 17.4  .VO1NA.
23:00 14.6 15.9
00:00  1.3  7.4
01:00  8.9 13.9
02:00 16.0 18.3  GN BOB!
03:00  4.2  8.8
04:00  7.0  8.9
05:00 13.2 15.9  -VO1NA-
06:00 11.7 14.6
07:00 10.9 13.8
08:00  1.3  0.8

K3RWR 137479 Hz:
        DF6NM
start  sym  car  message
22:00  3.4  4.5  GL_73
22:30  3.4  5.2
00:30  5.4  7.9  EB/N0
01:00  6.4  8.1
01:30  3.0  3.8
02:00  5.1  6.1
02:30  8.7  8.3  *RWR*
03:30  4.9  5.5
04:00  8.1  8.7
04:30  5.2  7.9
05:00  0.5  2.5
05:30  5.3  5.9
06:30  3.7  5.2
07:00  4.8  4.8
07:30  1.7  0.2

If you guys want to continue tonight I will try to run autodecoders on both sites: 
http://df6nm.darc.de/opds/ebnautresults.txt
https://vlf.u01.de/LF/LFgrabber/ebnautresults.txt

All the best,
Markus (DF6NM)


-----Ursprüngliche Mitteilung-----
Von: jrusgrove@comcast.net <jrusgrove@comcast.net>
An: rsgb_lf_group@blacksheep.org <rsgb_lf_group@blacksheep.org>
Verschickt: So, 9. Dez 2018 1:50
Betreff: Re: LF: LF and VLF EbNaut

Rob

 

Continued 'perfect' reception with CW ID.

 

 

 

Jay W1VD

 

 

----- Original Message -----

From: Rob Renoud <k3rwr@md.metrocast.net>

Reply-To: <rsgb_lf_group@blacksheep.org>

To: <rsgb_lf_group@blacksheep.org>

Sent: 12/8/2018 4:17:50 PM

Subject: Re: LF: LF and VLF EbNaut

---

LF EbNaut & Markus,

There is a definite post sunset opening to Europe from the NA East Coast.

I have modified my station to overlay a 10 minute CW ID (off-on CW modulation at 20 wpm) on the EbNaut message stream.  Will be interested to see what effect it has on decodes.  Am still transmitting a 5 character text message as before.

Tnx es 73,

Rob - K3RWR

On Dec 8, 2018, at 10:57, Markus Vester <markusvester@aol.com> wrote:

Here are the Bavarian decodes from last night's sesseion. Eb/N0 values derived from symbol error rate and carrier power were sometimes rather inconsistent so both are mentioned here. As expected, the quiet DL0AO site is generally a few dB better than mine, decoding VO1NA consistently in every single slot.

I was amazed by the early start from Canada. At this time of the year, such northerly paths are apparently close enough to darkness almost around the clock. My 100 kHz monitor shows Loran signals from East China rolling in already around midday here.

EbNaut Decodes 2018-12-07/08

VO1NA 137477 Hz:
        DF6NM       DL0AO
start  sym  car    sym  car
17:00  3.3  3.1    5.8  5.2  MARCONI
18:00  8.6  9.5   12.3 13.3
19:00  5.7  7.4    6.7  7.1
20:00  4.0  1.9   12.0  7.8
21:00  2.3  5.0   11.8  7.3
22:00  7.1  7.9   13.4 12.2
23:00 10.7 10.8   10.5  8.9
00:00  9.5  8.4   12.1  4.3
01:00  9.8  8.5   11.9  8.2  *******
02:00  2.4  1.9    7.2  6.1  -VO1NA-
03:00  7.3  4.1    4.2 -1.3
04:00  1.7  3.0    5.5  2.9
05:00  8.5  5.4    8.3  4.2
06:00     ---     10.0  8.9
07:00  5.7  5.8    6.6  7.2
08:00     ---      3.1  2.3 (+0.2 mHz)

K3RWR 137479 Hz:
        DF6NM       DL0AO
start  sym  car    sym  car
20:00     ---         ---    K3RWR
20:30     ---         --- 
21:00  2.3  1.5       ---
21:30     ---         --- 
22:00     ---      2.0 -1.8
22:30     ---         --- 
23:00     ---      4.6  0.1 
23:30  6.4  3.1   11.3  8.2
00:00  5.0  2.7    3.9 -3.5
00:30  5.4  4.8       ---
01:00     ---         ---
01:30     ---         ---
02:00  5.1  3.9    3.6  3.1
02:30     ---      1.2 -0.8
03:00     ---         ---
03:30     ---         ---
04:00  2.8  0.4       ---
04:30  0.9 -1.3    5.5  1.5
05:00  6.4  1.9    4.0 -1.6
05:30  4.0  0.4    5.9 -0.5
06:00 -1.6 -1.7    1.2 -0.1
06:30     ---      4.4  0.1
07:00     ---         ---
07:30     ---      1.4  1.8
08:00     ---      0.4  0.2

Best 73,
Markus