Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id v8UMplhY000973 for ; Sun, 1 Oct 2017 00:51:50 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1dyQVt-00046z-TU for rs_out_1@blacksheep.org; Sat, 30 Sep 2017 23:45:37 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1dyQVO-00046o-Lx for rsgb_lf_group@blacksheep.org; Sat, 30 Sep 2017 23:45:06 +0100 Received: from omr-a009e.mx.aol.com ([204.29.186.49]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.89) (envelope-from ) id 1dyQVH-0002FC-K4 for rsgb_lf_group@blacksheep.org; Sat, 30 Sep 2017 23:45:05 +0100 Received: from mtaomg-maa02.mx.aol.com (mtaomg-maa02.mx.aol.com [172.26.222.144]) by omr-a009e.mx.aol.com (Outbound Mail Relay) with ESMTP id 973CC3800092 for ; Sat, 30 Sep 2017 18:44:54 -0400 (EDT) Received: from core-ace10g.mail.aol.com (core-ace10.mail.aol.com [172.27.23.10]) by mtaomg-maa02.mx.aol.com (OMAG/Core Interface) with ESMTP id 3996738000081 for ; Sat, 30 Sep 2017 18:44:54 -0400 (EDT) Received: from 188.192.44.165 by webjas-vac187.srv.aolmail.net (10.96.19.190) with HTTP (WebMailUI); Sat, 30 Sep 2017 18:44:53 -0400 Date: Sat, 30 Sep 2017 18:44:54 -0400 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <15ed4f6be21-c03-49e19@webjas-vac187.srv.aolmail.net> In-Reply-To: <59C901BF.2050901@posteo.de> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [188.192.44.165] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1506811494; bh=dj/grYArV7QkkEdjajFIClrn5P6rRx4kDESu1WGtIlI=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=MZJzUV2vy17L5CoZLgeflL6wssDxAcL8mEMnWjy+MgClk9ga6bCX8IPjV85DZADlE LhwmirER8my3AWuiZ3bxEHd0DDDHOyTxDAHEPTKaPRp7blkrYvis268EDQi199NZFd WvJI5OxI6UxYY5/EOkBmsYtZR0WG4ldRGm3otWBg= x-aol-sid: 3039ac1ade9059d01e667c9d X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Those ZEVS messages seem to consist of simple three-digit numbers. With 0.2 Hz spacing, the frequency ranges 81 to 81.8 and 82.2 to 83 Hz provide ten possible MFSK symbols. Each message is sent twice, separated by a single 80.8 Hz dash. Consecutive messages are always separated by the 82 Hz idle tone. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: ecf102e6d15c1e466f357d5e6d956ac3 Subject: Re: ELF: ZEVS reception from a small loop Content-Type: multipart/alternative; boundary="----=_Part_369980_1233319349.1506811493921" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=HTML_MESSAGE autolearn=no version=2.63 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 ------=_Part_369980_1233319349.1506811493921 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Those ZEVS messages seem to consist of simple three-digit numbers. With 0.2= Hz spacing, the frequency ranges 81 to 81.8 and 82.2 to 83 Hz provide ten = possible MFSK symbols. Each message is sent twice, separated by a single 80= .8 Hz dash. Consecutive messages are always separated by the 82 Hz idle ton= e. Assuming that symbol frequencies are counted upwards from 0 to 4 and 5 to 9= , Stefan's screenshot would translate to ..7 486 128 731 941 473 018 =20 73, Markus =20 -----Urspr=C3=BCngliche Mitteilung-----=20 Von: DK7FC An: rsgb_lf_group Cc: Renato Romero Verschickt: Mo, 25. Sept 2017 15:18 Betreff: ELF: ZEVS reception from a small loop Hi LF friends,=20 You know, a few weeka ago i've been in France. We had a field day and i te= sted my small loop with its new preamp. Description below. From a handy loop with just 0.8 m diameter and 84 turns i didn't expect mu= ch. However i saw my 4470.005 Hz carrier quite well even in 424 uHz FFT ban= dwidth which is not bad at all for 250 km distance. It even was a noisy day= . But now: I reprocessed the recording (which was done by the Raspi and vlfr= x tools) again, looking for ZEVS on 82 Hz. To my surprise ZEVS has a very good SNR from that small antenna! It was up= to 25 dB in 3.8 mHz! That's the celarest signal i saw from ZEVS, so far. F= or the spectrogram i used a 1.5 kHz low pass filter and a noise blanker. See: http://www.iup.uni-heidelberg.de/schaefer_vlf/VLF/ZEVS__from_JN29PD06B= O.png So my loop setup seems to be promising for the next 970 Hz experiment as w= ell :-) 73, Stefan PS: The preamp design is taken from: http://www.vlf.it/feletti2/idealloop.= html Am 18.09.2017 00:56, schrieb DK7FC:=20 Am 31.08.2017 22:37, schrieb DK7FC:=20 This weekend i will be in France again, JN29OD96SK , on a field day with th= e radio club. I plan to receive the 4470 Hz signal with a small loop and it= s new preamp and the octo soundcard. Thus i want to run a carrier again on = 4470.005 Hz. Tomorrow, Friday, i will transmit the EbNaut message again. Af= ter that, the carrier will continue until sunday. With some luck i hope you= can decode the message when including the friday transmission. If not, i c= ould continue to transmit on monday... It took some time but now i have some results from that experiment. I actu= ally placed a 84 turn loop with 0.8 m diameter and a low noise preamp betwe= en some trees in France, JN29PD06BO. A path of 250 km or 3.7 wavelengths between RX and TX ( http://no.nonsense= .ee/qth/map.html?qth=3DJN29PD06BO&from=3Djn49ik00wd ). Quite a compact RX s= ystem for VLF. I did not prepare the experiment as good as possible, there = was no E field RX together with the loop. H field only. It was mainly anoth= er test of the octo-soundcard and a first test for the samll loop and its L= NA.=20 I converted the data files recorded by vlfrx tools into a wav file and ana= lysed it in SpecLab. Here is a wideband spectrogram showing the QRN: http:/= /www.iup.uni-heidelberg.de/schaefer_vlf/VLF/wide4470.png (time markers are = incorrect there) On sunday morning, 3rd Spetember when i looked at the installation i found= that the preamp was disconnected from the battery. It must have been an an= imal walking arround into the field, stumbling over the cable ;-) . Fortuna= tely the interruption took just about one hour ;-) Assuming that vlfrx tools correctly resampled to 24 kS/s i run the file in= to SpecLab set to 47 uHz FFT bin width, hoping to see a trace/peak at 4470.= 005 Hz.=20 And indeed, there is something! See attachment. That's a first trace from = DL to F on the 67 km band :-) About 18 dB in 47 uHz during the best time, m= uch more than i expected. Another success is that i managed to produce a first spectrum peak and gen= erated a png file using vlfrx tools. The procedure is based on Paul's advic= e. :-) 73, Stefan ------=_Part_369980_1233319349.1506811493921 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Those ZEVS messages seem to consist of simple three-digi= t numbers. With 0.2 Hz spacing, the frequency ranges 81 to 81.8 and 82.2 to= 83 Hz provide ten possible MFSK symbols. Each message is se= nt twice, separated by a single 80.8 Hz dash. Consecutive me= ssages are always separated by the 82 Hz idle tone.

Assuming that&nb= sp;symbol frequencies are counted upwards from 0 to 4 and 5 to 9, = ;Stefan's screenshot would translate to

..7 486 128   = ;731    941        473   = 018
 
73, Markus  


-----Urspr=C3=BCngliche = Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_l= f_group <rsgb_lf_group@blacksheep.org>
Cc: Renato Romero <conta= ct@vlf.it>
Verschickt: Mo, 25. Sept 2017 15:18
Betreff: ELF: ZEVS = reception from a small loop

Hi LF friends,

You know, a few weeka ago i've been in France. We had a field day and i tested my small loop with its new preamp. Description below.
>From a handy loop with just 0.8 m diameter and 84 turns i didn't expect much. However i saw my 4470.005 Hz carrier quite well even in 424 uHz FFT bandwidth which is not bad at all for 250 km distance. It even was a noisy day.

But now: I reprocessed the recording (which was done by the Raspi and vlfrx tools) again, looking for ZEVS on 82 Hz.
To my surprise ZEVS has a very good SNR from that small antenna! It was up to 25 dB in 3.8 mHz! That's the celarest signal i saw from ZEVS, so far. For the spectrogram i used a 1.5 kHz low pass filter and a noise blanker.
See: http://www.iup.uni-heidelberg.de/schaefer_vlf/VLF/= ZEVS__from_JN29PD06BO.png

So my loop setup seems to be promising for the next 970 Hz experiment as well :-)

73, Stefan

PS: The preamp design is taken from: http://www= .vlf.it/feletti2/idealloop.html


Am 18.09.2017 00:56, schrieb DK7FC:
=20
Am 31.08.2017 22:37, schrieb DK7FC:
=20 =20 This weekend i will be in France again, = JN29OD96SK , on a field day with the radio club. I plan to receive the 4470 Hz signal with a small loop and its new preamp and the octo soundcard. Thus i want to run a carrier again on 4470.005 Hz. Tomorrow, Friday, i will transmit the EbNaut message again. After that, the carrier will continue until sunday. With some luck i hope you can decode the message when including the friday transmission. If not, i could continue to transmit on monday...

It took some time but now i have some results from that experiment. I actually placed a 84 turn loop with 0.8 m diameter and a low noise preamp between some trees in France, JN29PD06BO.
A path of 250 km or 3.7 wavelengths between RX and TX ( http://no.nonsense.ee/qth/map.html?qth=3DJN29PD06B= O&from=3Djn49ik00wd ). Quite a compact RX system for VLF. I did not prepare the experiment as good as possible, there was no E field RX together with the loop. H field only. It was mainly another test of the octo-soundcard and a first test for the samll loop and its LNA.
I converted the data files recorded by vlfrx tools into a wav file and analysed it in SpecLab. Here is a wideband spectrogram showing the QRN: http://www.iup.uni-heidelberg.de/schaefer_vlf/VLF/wide4470.png= (time markers are incorrect there)

On sunday morning, 3rd Spetember when i looked at the installation i found that the preamp was disconnected from the battery. It must have been an animal walking arround into the field, stumbling over the cable ;-) . Fortunately the interruption took just about one hour ;-)
Assuming that vlfrx tools correctly resampled to 24 kS/s i run the file into SpecLab set to 47 uHz FFT bin width, hoping to see a trace/peak at 4470.005 Hz.
And indeed, there is something! See attachment. That's a first trace from DL to F on the 67 km band :-) About 18 dB in 47 uHz during the best time, much more than i expected.

Another success is that i managed to produce a first spectrum peak and generated a png file using vlfrx tools. The procedure is based on Paul's advice. :-)

73, Stefan










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