Re: VLF: EbNaut message announcement @ 5170

[Markus Vester <markusvester@aol.com>]

A perfect and obviously correct decode from DL0AO.

Eb/N0 from EW earth loop:
12.3 dB (carrier), 12.3 dB (symbol err.)

Eb/N0 from E-field:
12.1 dB (carrier), 11.9 dB (symbol err.)

Eb/N0 from cardioid (180° sum, H-E):
14.7 dB (carrier), 14.5 dB (symbol err.)

Best 73,
Markus



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Sa, 16. Mrz 2019 15:56
Betreff: Re: VLF: EbNaut message announcement @ 5170

Hello Markus and Paul, VLF,

Many thanks for the feedback. What a great result!
Paul, after the EbNaut transmission i sent '73' in DFCW-90, which is a typical mode for LF operation. Do you see the message in a spectrogram, like Markus did at DL0AO? Best setting may be something like 20 mHz and 10 sec/pixel.

On my tree (meanwhile shutdown because the old accu is empty!) the E field is still not really usable but the loops work very well on that frequency. Mixing both loops and optimising the settings gives carrier S/N: 48.05 dB in 282.5 uHz for the carrier transmission!
So i could see a clear trace from a 1 W transmitter!

I'll produce a spectrogram from the postprocessed data...

Maybe Jacek got something too? :-)

73, TNX, Stefan


Am 16.03.2019 15:29, schrieb Paul Nicholson:

Stefan wrote:

> The carrier is now running since 09:31 UTC at 5170.1 Hz.

Enormous signal here -

 http://abelian.org/vlf/tmp/190316a.png

S/N 33.6 dB in 278uHz, -2dB in 1Hz, -36dB in 2.5kHz.

> Message:
> *f = 5170.1 Hz

> Symbol period: 2 s
> Characters: 14
> CRC bits: 14
> Coding 16K21A

> start at 10:30:00.3 UTC.

Decoded rank 0 BER 8.9% constant reference phase.

carrier Eb/N0: 10.3 dB
carrier S/N: 29.3 dB in 264.8 uHz, -6.5 dB in 1Hz, -40.5 dB in 2.5kHz

--
Paul Nicholson
--

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