Return-Path: X-Spam-DCC: paranoid 1290; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.3 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_30_40,HTML_MESSAGE,RATWARE_GECKO_BUILD,SPF_PASS autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id u4I8JCjK007220 for ; Wed, 18 May 2016 10:19:12 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1b2wbq-00008z-U9 for rs_out_1@blacksheep.org; Wed, 18 May 2016 09:13:38 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1b2wbp-00008p-Q8 for rsgb_lf_group@blacksheep.org; Wed, 18 May 2016 09:13:37 +0100 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1b2wbn-0002QY-Ly for rsgb_lf_group@blacksheep.org; Wed, 18 May 2016 09:13:36 +0100 Received: from dovecot03.posteo.de (dovecot03.posteo.de [172.16.0.13]) by mout01.posteo.de (Postfix) with ESMTPS id 82A0A20A70 for ; Wed, 18 May 2016 10:13:33 +0200 (CEST) Received: from mail.posteo.de (localhost [127.0.0.1]) by dovecot03.posteo.de (Postfix) with ESMTPSA id 3r8n5T3xk0z5vN5 for ; Wed, 18 May 2016 10:13:33 +0200 (CEST) Message-ID: <573C242D.4010709@posteo.de> Date: Wed, 18 May 2016 10:13:33 +0200 From: DK7FC User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <154c2af3eeb-799f-23f79@webprd-a77.mail.aol.com> In-Reply-To: <154c2af3eeb-799f-23f79@webprd-a77.mail.aol.com> X-Scan-Signature: e3d323418d60e0f7f0af176deb9f3e2b Subject: Re: VLF: EbNaut transmissions on lower frequencies?, pre-tests: 6.47kHz Content-Type: multipart/alternative; boundary="------------010006000807020505020604" X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.56 on 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 8110 This is a multi-part message in MIME format. --------------010006000807020505020604 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hello Markus, Paul, VLF, Oh, what a surprise! You've got the message with such a high SNR? It is amazing. Congrats to your first decode on 6.47 kHz! What happened to your QRM? I the Bahn striking again? Strange, i saw that the message was finished earlier than expected. Actually it should be 20 characters. The message should be 'STEFAN&PAUL@6.47KHZ!' but the '&' and '!' was ignored. The EbNaut-TX program confirmed 20 characters after writing them in the text field though. The message was placed into a night-day-night period and QRN was moderate. Paul said that night propagation is better than day propagation and maybe the QRN of the night is rather in the 'foreground' so it can be blanked more effective. BTW the antenna current was even 250 mA and quite constant! Yesterday i considered to solder on the PA and add new components while it was transmitting ;-) But then i convinced myselfe to continue on other projects ;-) But today is the day.. Now i hope for Paul to get some good results. 73 and thanks for trying to receive/decode. Stefan Am 18.05.2016 09:05, schrieb Markus Vester: > Hi Stefan, Paul, > > that message was only 18 characters long! Decode attached. > > 73, Markus > > > > -----Ursprüngliche Mitteilung----- > Von: DK7FC > An: rsgb_lf_group > Verschickt: Mo, 16 Mai 2016 10:53 pm > Betreff: Re: VLF: EbNaut transmissions on lower frequencies?, > pre-tests: 6.47kHz > > Hi Paul, VLF, > > A spontaneous impulse/idea: > > Let's be optimistic and try the long message in 100s symbols. The > announcement happens a few minutes before the start of the > transmission :-) > > *f = 6470.00000 Hz > Start time: 16.05.2016 21:00:02 UTC > Symbol length: 100 s > Characters: 20 > CRC 16 > Coding 8K19A > Duration: 34h, 13m, 20s* > *Antenna current: 240 mA* > > 16K25A and 200s, that's a job for the lower frequencies. I have to > send the mail now, otherwise it comes to late ;-) > > 73, Stefan > > Am 16.05.2016 07:38, schrieb Paul Nicholson: > > > Stefan wrote: > > > would you think that going from 100s to 200s will improve > > things by about 3 dB? > > Yes, or better: keeping to 100s and going to a 16K mode instead > of 8K for an increase of coding gain. > > > How long do you record the VLF soundcard stream? > > About 65 months at the moment. > > > Would it be possible, for example, to transmit a 1 week long > > message, without an announcement before the start? > > Yes, in principle. The longer the message the more chance of > a battery problem or sheep knocking down one of the antennas, > or thunderstorm or power cut, or one of the cats sleeping on > top of the GPS antenna. > > But with a long message, an interruption of a few hours is > not a disaster. After a power cut, my rx will restart with > the same reference phase and continue recording so there will > be a gap but no loss of phase. > > We may have to put this to use when we reach ULF. > > Un-announced is ok because of the continuous recording but better > to announce if possible so that I know not to do maintenance > (or tests with kites! Will be playing with the Power Sled 24). > > -- > Paul Nicholson > -- > --------------010006000807020505020604 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello Markus, Paul, VLF,

Oh, what a surprise! You've got the message with such a high SNR? It is amazing. Congrats to your first decode on 6.47 kHz!
What happened to your QRM? I the Bahn striking again?

Strange, i saw that the message was finished earlier than expected. Actually it should be 20 characters. The message should be 'STEFAN&PAUL@6.47KHZ!' but the '&' and '!' was ignored.
The EbNaut-TX program confirmed 20 characters after writing them in the text field though.

The message was placed into a night-day-night period and QRN was moderate. Paul said that night propagation is better than day propagation and maybe the QRN of the night is rather in the 'foreground' so it can be blanked more effective.
BTW the antenna current was even 250 mA and quite constant!
Yesterday i considered to solder on the PA and add new components while it was transmitting ;-) But then i convinced myselfe to continue on other projects ;-) But today is the day..

Now i hope for Paul to get some good results.

73 and thanks for trying to receive/decode.
Stefan

Am 18.05.2016 09:05, schrieb Markus Vester:
Hi Stefan, Paul,

that message was only 18 characters long! Decode attached.

73, Markus



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Mo, 16 Mai 2016 10:53 pm
Betreff: Re: VLF: EbNaut transmissions on lower frequencies?, pre-tests: 6.47kHz

Hi Paul, VLF,

A spontaneous impulse/idea:

Let's be optimistic and try the long message in 100s symbols. The announcement happens a few minutes before the start of the transmission :-)

f = 6470.00000 Hz
Start time: 16.05.2016   21:00:02 UTC
Symbol length: 100 s
Characters: 20
CRC 16
Coding 8K19A
Duration: 34h, 13m, 20s
Antenna current: 240 mA

16K25A and 200s, that's a job for the lower frequencies. I have to send the mail now, otherwise it comes to late ;-)

73, Stefan

Am 16.05.2016 07:38, schrieb Paul Nicholson:

Stefan wrote:

> would you think that going from 100s to 200s will improve
> things by about 3 dB?

Yes, or better: keeping to 100s and going to a 16K mode instead
of 8K for an increase of coding gain.

> How long do you record the VLF soundcard stream?

About 65 months at the moment.

> Would it be possible, for example, to transmit a 1 week long
> message, without an announcement before the start?

Yes, in principle.  The longer the message the more chance of
a battery problem or sheep knocking down one of the antennas,
or thunderstorm or power cut, or one of the cats sleeping on
top of the GPS antenna.

But with a long message, an interruption of a few hours is
not a disaster.  After a power cut, my rx will restart with
the same reference phase and continue recording so there will
be a gap but no loss of phase.

We may have to put this to use when we reach ULF.

Un-announced is ok because of the continuous recording but better
to announce if possible so that I know not to do maintenance
(or tests with kites! Will be playing with the Power Sled 24).

--
Paul Nicholson
--

--------------010006000807020505020604--