Re: LF: New EbNaut tx: R7NT

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

Hello LF, EbNauters

my rx setup was not ready to pick-up earlyer R7NT's  transmissions.

The first usable file starts at 15:38 UT. I used this file to catch the 15:30 transmission (-484.6 s) and i got the decode !

First EbNaut R -> I . Thank you Alex !

Of course Eb/N0 is invalid due to plenty symbols missed.

I tryed to decode following transmissions without results (yet). It is hard becouse of frequency drift due to transmitter and propagation. Maybe a shorter message (less characters) can help.

Alex, can you tell us witch setup are you using ?

In the folder http://qsl.net/i/iz7slz//R7NT/ i have uploaded some .wav files, maybe someone is more lucky and skilled  then me in catching !

73 to all,

Domenico iz7slz

On 18 December 2016 at 19:41, Markus Vester <markusvester@aol.com> wrote:

No I believe it's the transmitter itself, probably temperature drift of a crystal oscillator. We also find a similar frequency variation in R7NT's opds spots. For EbNaut, 5 milliHz is quite a lot. 

73, Markus (DF6NM)



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: So, 18 Dez 2016 7:25 pm
Betreff: Re: LF: New EbNaut tx: R7NT

Hello Markus,

Such a small drift, could it be propagation? It was during the onset of the night.

I played a bit further and changed the frequency offset from 41.993 Hz to 41.9931 Hz and got a 0.8 dB better Eb/N0.

73, Stefan

Am 18.12.2016 18:42, schrieb Markus Vester:

Got a valid decode here as well. The signal is quite strong, but drifted by about 5 milliHz.

Best 73,
Markus



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: So, 18 Dez 2016 6:18 pm
Betreff: Re: WG: LF: New EbNaut tx: R7NT

Hi Alex, LF,

Also copied R7NT here in Heidelberg. An early decode. First decode from Russia here.
There is an offset of -7 mHz. First i tried 42 Hz offset (offset to 137.5 kHz) and got no decode. It shows how critical the timing is. But it also shows how helpful Markus' 'show_rawsyms3b' feature is.

73, Stefan

Von: Alex K
Gesendet: Sonntag, 18. Dezember 2016 12:47
An: rsgb_lf_group; rsgb_lf_group
Cc: Markus Vester
Betreff: New EbNaut tx: R7NT

 

Hello LF!
R7NT is now txing EbNaut
--------------------------
Freq:   137542.00
Code:   8K19A
Symbol:   2.0 s
Len:   8
Time:   1312.0 s (21m 52.0s)
Every hh:00 and hh:30 min
----------------------------


--
Alex RN3AUS

 

 

Screenshot R7NT 2016-12-18.png
Description: PNG image

Screenshot decode R7NT 2016-12-18.png
Description: PNG image