Re: VLF: First VLF detection DL > EA

[DK7FC <selberdenken@posteo.de>]

Hi VLF,

Tomorrow i'm going to gtry to pass a first EbNaut message over to EA5DOM. Here are the details:

f = 17470.1000 Hz
Start time: 05.Dec.2017  07:00:00 UTC
Symbol period: 120 s
Characters: 1
CRC bits: 6
Coding 8K19A
Duration: 08:00 [hh:mm]
Antenna current: 1 A

73, Stefan


Am 02.12.2017 13:31, schrieb VIGILANT Luis Fernández:

Hi VLF

Congratulations Stefan and thank you all for the good information exchanges in the reflector

It is all the effort at your side Stefan. I still didn't do the homework to decrease the local QRM, which is

quite high as you can see in the 25KHz spectrogram. There is a very nasty noise which appeared just

this last couple of days and affects exactly 17470Hz. It is random and runs for a couple hours. Can be seen

as vertical noise lines in the lower spectrograms and is very noticeable in the 47uH spectrogram

It is my first detection of Ham activity under LF so far. And there is a lot to improve to get same results

at 8270Hz. A new Rx setup in a different (hopefully cleaner) QTH is in the "To Do" list ;-)

73 de Luis

EA5DOM 

---

De: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] en nombre de Daniele Caccia [daniele.caccia74@gmail.com]
Enviado: sábado, 2 de diciembre de 2017 12:07
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: VLF: First VLF detection DL > EA

Dear VLF er

Congratulations to all for the results obtained so far!

Best regards from Daniele SWL I55387FI -ITALY-

 

2017-12-02 10:30 GMT+01:00 Alberto Martinez <ea4ghb@gmail.com>:

Congratulation Stefan and Luis!

It´s weak but seeable. very good work.

73.

Alberto-EA4GHB

2017-12-02 9:57 GMT+01:00 DK7FC <selberdenken@posteo.de>:

Hello VLF friends,

This morning i looked on the EA5DOM VLF grabber and saw much better traces of the carrier on 17.4701 kHz.
https://ea5dom.ure.es/grabber/index.html

I find this is a valid one-way contact or carrier detection and i think it is the first time that this was done by amateurs between DL and EA.
A distance of 1393 km, http://k7fry.com/grid/?qth=IM98XN&from=jn49ik00wd

It looks like there is some QSB on that path, higher than observed a similar distance at 8270 Hz.
We can now think about improvements and about a first message attempt...

73, Stefan