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 w911L1OI015082 for ; Mon, 1 Oct 2018 03:21:04 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1g6moV-0006K5-EU for rs_out_1@blacksheep.org; Mon, 01 Oct 2018 02:15:55 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1g6moU-0006Jw-OR for rsgb_lf_group@blacksheep.org; Mon, 01 Oct 2018 02:15:54 +0100 Received: from omr-m011e.mx.aol.com ([204.29.186.11]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.91_59-0488984) (envelope-from ) id 1g6moR-0001to-9T for rsgb_lf_group@blacksheep.org; Mon, 01 Oct 2018 02:15:53 +0100 Received: from mtaomg-mbd01.mx.aol.com (mtaomg-mbd01.mx.aol.com [172.26.252.15]) by omr-m011e.mx.aol.com (Outbound Mail Relay) with ESMTP id 7825638000A0 for ; Sun, 30 Sep 2018 21:15:49 -0400 (EDT) Received: from core-acx15a.mail.aol.com (core-acx15.mail.aol.com [10.74.43.2]) by mtaomg-mbd01.mx.aol.com (OMAG/Core Interface) with ESMTP id 314AC38000081 for ; Sun, 30 Sep 2018 21:15:49 -0400 (EDT) Received: from 188.194.221.221 by webjasstg-vab21.srv.aolmail.net (10.96.25.88) with HTTP (WebMailUI); Sun, 30 Sep 2018 21:15:48 -0400 Date: Sun, 30 Sep 2018 21:15:49 -0400 From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-Id: <1662d3211e5-1ec3-24aa@webjasstg-vab21.srv.aolmail.net> In-Reply-To: <019501d45915$822b5450$8681fcf0$@comcast.net> MIME-Version: 1.0 X-MB-Message-Source: WebUI X-MB-Message-Type: User X-Mailer: JAS STD X-Originating-IP: [188.194.221.221] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20150623; t=1538356549; bh=3pavhBW62a60UiKf2L2nRq/Mej7pol1Ub/oAVm4D5ok=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=bYvlVmtnC0RuTX9YIpz743QfHAYs7Sj0TiVYbyyolO46Jx9Hx2SAUJ0V/SH8grdOG UbC7HDyUEGLbdkfisHAoIu4mJO2+Gq1P5U6Mu7rJHWLuzB6LqfpmMwefUykM/qunRh sNcd7R3KbriJQJiRYS0b2SHxarjrCIdI7cHveYmk= x-aol-sid: 3039ac1afc0f5bb1754529b9 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 @@CONTACT_ADDRESS@@ for details. Content preview: Hi Stefan, congratulations also from my end! The fact that you did receive the signal well on one loop but not on the E-Field remains a big riddle. One thought just crossed my mind: The Rhine river might behave as a large conductor, extending South-to-North more or less in the middle between the antennas. There are probably also railway and electric power lines running along the valley. At this frequency, magnetic fields are penetrating deeply into the ground, and might encircle and magnetically couple to this conductor from either side. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [204.29.186.11 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 T_KAM_HTML_FONT_INVALID BODY: Test for Invalidly Named or Formatted Colors in HTML 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: 9c6f861813be21b949fefb381c49ca48 Subject: Re: LF: RE: The next experiment on 970 Hz - Cracked the far field border below 1 kHz Content-Type: multipart/alternative; boundary="----=_Part_11850_617421332.1538356548068" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.8 required=5.0 tests=HTML_30_40,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_11850_617421332.1538356548068 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Stefan,=20 congratulations also from my end! The fact that you did receive the signal = well on one loop but not on the E-Field remains a big riddle.=20 One thought just crossed my mind: The Rhine river might behave as a large c= onductor, extending South-to-North more or less in the middle between the a= ntennas. There are probably also railway and electric power lines running a= long the valley. At this frequency, magnetic fields are penetrating deeply = into the ground, and might encircle and magnetically couple to this conduct= or from either side. One question is whether the H-field is stronger than expected or the E-fiel= d is too weak. This might be answered by calibrating the TX and RX antennas= and measuring absolute levels. The loop area (or "effective depth") of the= TX antenna might be obtained in receive mode by comparing induced voltage = with a small test loop, using manmade VLF signals or spherics at different = frequencies and extrapolating to 970 Hz. ZEVS might provide another data po= int (if it's azimuth is not too far off the maximum from the earth antenna)= . Best 73, Markus (DF6NM) -----Urspr=C3=BCngliche Mitteilung-----=20 Von: hvanesce An: rsgb_lf_group Verschickt: Mo, 1. Okt 2018 1:32 Betreff: LF: RE: The next experiment on 970 Hz - Cracked the far field bord= er below 1 kHz #AOLMsgPart_2_4d8f7e86-e218-443c-be2e-f2f2308caec1 td{color: black;} @font-= face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4;}@font-face {font-= family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;}.aolReplacedBody p.aolmail_Ms= oNormal,.aolReplacedBody li.aolmail_MsoNormal,.aolReplacedBody div.aolmail_= MsoNormal {margin:0in; margin-bottom:.0001pt; font-size:12.0pt; font-family= :"Times New Roman","serif"; color:black;}.aolReplacedBody a:link,.aolReplac= edBody span.aolmail_MsoHyperlink {mso-style-priority:99; color:blue; text-d= ecoration:underline;}.aolReplacedBody a:visited,.aolReplacedBody span.aolma= il_MsoHyperlinkFollowed {mso-style-priority:99; color:purple; text-decorati= on:underline;}.aolReplacedBody span.aolmail_EmailStyle17 {mso-style-type:pe= rsonal-reply; font-family:"Calibri","sans-serif"; color:#1F497D;}.aolReplac= edBody .aolmail_MsoChpDefault {mso-style-type:export-only; font-size:10.0pt= ;}@page WordSection1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in;}.a= olReplacedBody div.aolmail_WordSection1 {page:WordSection1;} Stefan, =20 Congratulations! A great milestone for many reasons. =20 Amazing to think of far-field at that frequency without tons of antenna; a = credit to design, test planning, and test execution. =20 Below 2 KHz is new territory for many reasons including markedly different = sky propagation and changing earth propagation which also affects the chara= cter of noise*. =20 Your (more than) year of considerable effort toward this goal probably kept= many on the edge of their seats, me included, I=E2=80=99m celebrating. =20 In free space the electric field at a receiving antenna 0.18 wavelengths aw= ay from a transmitting loop antenna should be very good compared to the mag= netic field at the same receiving location. But for a ground loop transmitting antenna at 970 Hz I wonder if anyone kno= ws which field (E or B) and which polarization (theta and phi) predominates= at a receiving antenna near the ground at 0.18 wavelengths distance. A ver= y interesting topic and perhaps your E-field (monopole) and B field (loop) = receiving antennas have provided another milestone in this respect: perhaps= a first documented data point for E vs. B at any polarization, near 0.18 w= avelengths (an interesting distance on its own) from a ground-loop transmit= ting antenna at 970 Hz? =20 Another fascinating realm now opened, much appreciated. 73, Jim AA5BW =20 =20 *(noise characteristics including noise E strength vs. B strength vs. noise= polarization vs. distance from noise source vs noise-source-type could be = interesting at 970Hz) =20 =20 =20 =20 From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacks= heep.org] On Behalf Of DK7FC Sent: Saturday, September 29, 2018 5:00 PM To: rsgb_lf_group@blacksheep.org Subject: ULF: The next experiment on 970 Hz - Cracked the far field border = below 1 kHz =20 Hi ULF,=20 Today i run a carrier transmission on 970.01 Hz. Start time was 08:05 UTC. = The carrier run for 3 hours without an interruption. I got 1.9 A antenna cu= rrent on my ground loop antenna, about 320 W DC input to the PA. The signal was received on my 3-axis RX on the tree in JN49IK. The distance= was, as usual, 55.6 km. So far the results were disappointing. I expected a strong SNR (at least 10= dB in 424 uHz) from the new E field antenna which seems to perform very we= ll in the complete ULF range. However the analysis of a two hour segment of= the carrier showed an SNR of 6 dB, i.e. just noise. However, as i routinel= y calculated the SNR from the N-S loop i got a surprising SNR of 13.03 dB i= n 139.5 uHz. At about 08:40 UTC the reception on the tree was disturbed by its own solar= charger, just for a few seconds but that was enough to create a bright ver= tical line in the 424 uHz spectrogram showing the E field. Anyway, i just analysed the full 3 hour segment, only from the N-S loop (wh= ich actually points rather to 30/210 deg) and got the following result (inc= luding processing command line): vtread -T2018-09-29_08:05,+3h /raw | vtcat -p | vtmix -c0,1,0 | vtfilter -a= th=3D6 -h lp,f=3D1500,poles=3D8 | vtblank -a27 -d0.0005 -t100 | vtmult -f9= 70.01 | vtresample -r240 | vtresample -r1 | vtraw -oa | ebnaut -dp8K19A -r1= -c2 -v -f15 -f16 -M'***' -N3 -k20 -S24 carrier phase: -111.2 carrier Eb/N0: 1.9 dB carrier S/N: 14.25 dB in 93.0 uHz, -26.07 dB in 1Hz, -60.05 dB in 2.5kHz This is the first far field detection of a 970 Hz signal generated by amate= urs on the 309 km band! A true milestone for me. Since more than a year it = was my goal to cross that far field border on that band. :-) The efforts we= re immense. The result is just preliminary. I want to tweak the parameters for a higher= SNR and try to filter out the short QRM from the charger.=20 So now, why does the E field produce such bad results? At http://www.iup.un= i-heidelberg.de/schaefer_vlf/ULF/ULFSLFELF.png you can see what it receives= in the range of interest. The day/night QRN difference is higher than on t= he loops, so the loops seemed to be rather deaf. Does it maybe mean a steep= reflexion on the ionosphere, so that the E field antenna doesn't see it, b= ut the loops do? Later i've done a DC measurement and got 1 A at 86.5 V, quite much this tim= e. Maybe a bad contact somewhere. Will check that. My 120 Ah LiFePo4 accu is fully recharged and i plan to do a new experiment= on monday morning, 3 hours before my solar charger starts to work :-) The = SNR seems to be promising, i plan to send a 5 character EbNaut message. More results and a spectrum peak image will follow. 73, Stefan ------=_Part_11850_617421332.1538356548068 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Hi Stefan,

c= ongratulations also from my end! The fact that you did receive the signal w= ell on one loop but not on the E-Field remains a big riddle.

One thought just crossed my mind: The Rh= ine river might behave as a large conductor, extending South-to-North more = or less in the middle between the antennas. There are probably also railway= and electric power lines running along the valley. At this frequency, magn= etic fields are penetrating deeply into the ground, and might encircle and&= nbsp;magnetically couple to this conductor from either side.

One question is whether the H-field is stronger = than expected or the E-field is too weak. This might be answered by calibra= ting the TX and RX antennas and measuring absolute levels. The loop area&nb= sp;(or "effective depth") of the TX antenna might be obtained in recei= ve mode by comparing induced voltage with a small test loop, using man= made VLF signals or spherics at different frequencies and extrapolatin= g to 970 Hz. ZEVS might provide another data point (if it's azimuth is not = too far off the maximum from the earth antenna).

Best 73,
Markus (DF6NM)

=
-----Urspr=C3=BCngliche Mitteilung-----
Von= : hvanesce <hvanesce@comcast.net>
An: rsgb_lf_group &l= t;rsgb_lf_group@blacksheep.org>
Verschickt: Mo, 1. Okt 20= 18 1:32
Betreff: LF: RE: The next experiment on 970 Hz - Cra= cked the far field border below 1 kHz

Stefan,

 

Congratulations! A great milestone fo= r many reasons.

 

Amazing to think of far-field at= that frequency without tons of antenna; a credit to design, test planning,= and test execution.

<= span style=3D'color: rgb(31, 73, 125); font-family: "Calibri","sans-serif";= font-size: 11pt;' abp=3D"176"> 

Below 2 KHz is new territor= y for many reasons including markedly different sky propagation and changin= g earth propagation which also affects the character of noise*.

<= p class=3D"aolmail_MsoNormal" abp=3D"179">&= nbsp;

Your (more than) year of considerable effort toward this go= al probably kept many on the edge of their seats, me included, I=E2=80=99m = celebrating.

 

In free space the electric field a= t a receiving antenna 0.18 wavelengths away from a transmitting loop antenn= a should be very good compared to the magnetic field at the same receiving = location.

But for a ground loop transmitting antenna at 970 Hz I= wonder if anyone knows which field (E or B) and which polarization (theta = and phi) predominates at a receiving antenna near the ground at 0.18 wavele= ngths distance. A very interesting topic and perhaps your E-field (monopole= ) and B field (loop) receiving antennas have provided another milestone in = this respect: perhaps a first documented data point for E vs. B at any pola= rization, near 0.18 wavelengths (an interesting distance on its own) from a= ground-loop transmitting antenna at 970 Hz?

 

Ano= ther fascinating realm now opened, much appreciated.

=

= 73,

 

 

*(noise= characteristics including noise E strength vs. B strength vs. noise polari= zation vs. distance from noise source vs noise-source-type could be interes= ting at 970Hz)

 

 

&nb= sp;

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner= -rsgb_lf_group@blacksheep.org] On Behalf Of DK7FCSent: Saturday, September 29, 2018 5:00 PM<= br abp=3D"226">To: rsgb_lf_group@blacksheep.org
Subject: ULF: The next experiment on 970 Hz - Cracked the fa= r field border below 1 kHz

 

Hi UL= F,

Today i run a carrier transmission on 97= 0.01 Hz. Start time was 08:05 UTC. The carrier run for 3 hours without an i= nterruption. I got 1.9 A antenna current on my ground loop antenna, about 3= 20 W DC input to the PA.
The signal was received on my 3-axi= s RX on the tree in JN49IK. The distance was, as usual, 55.6 km.

So far the results were disappointing. I expected a st= rong SNR (at least 10 dB in 424 uHz) from the new E field antenna which see= ms to perform very well in the complete ULF range. However the analysis of = a two hour segment of the carrier showed an SNR of 6 dB, i.e. just noise. H= owever, as i routinely calculated the SNR from the N-S loop i got a surpris= ing SNR of 13.03 dB in 139.5 uHz.
At about 08:40 UTC the rec= eption on the tree was disturbed by its own solar charger, just for a few s= econds but that was enough to create a bright vertical line in the 424 uHz = spectrogram showing the E field.

Anyway, i j= ust analysed the full 3 hour segment, only from the N-S loop (which actuall= y points rather to 30/210 deg) and got the following result (including proc= essing command line):
vtread -T2018-09-29_08:= 05,+3h /raw | vtcat -p | vtmix -c0,1,0 | vtfilter -a th=3D6 -h lp,f=3D1500,= poles=3D8 | vtblank -a27 -d0.0005 -t100 | vtmult -f970.01 | vtresample -r24= 0 | vtresample -r1 | vtraw -oa | ebnaut -dp8K19A -r1 -c2 -v -f15 -f16 -M'**= *' -N3 -k20 -S24
carrier phase: -111.2
carrie= r Eb/N0: 1.9 dB
carrier S/N: 14.25 dB in 93.0 uHz, -26.07 dB= in 1Hz, -60.05 dB in 2.5kHz

This is the= first far field detection of a 970 Hz signal generated by amateurs on the = 309 km band! A true milestone for me. Since more than a year it was my goal= to cross that far field border on that band. :-) The efforts were immense.=
The result is just preliminary. I want to tweak the paramet= ers for a higher SNR and try to filter out the short QRM from the charger. =

So now, why does the E field produce such b= ad results? At h= ttp://www.iup.uni-heidelberg.de/schaefer_vlf/ULF/ULFSLFELF.png you can = see what it receives in the range of interest. The day/night QRN difference= is higher than on the loops, so the loops seemed to be rather deaf. Does i= t maybe mean a steep reflexion on the ionosphere, so that the E field anten= na doesn't see it, but the loops do?

Later i= 've done a DC measurement and got 1 A at 86.5 V, quite much this time. Mayb= e a bad contact somewhere. Will check that.

= My 120 Ah LiFePo4 accu is fully recharged and i plan to do a new experiment= on monday morning, 3 hours before my solar charger starts to work :-) The = SNR seems to be promising, i plan to send a 5 character EbNaut message.

More results and a spectrum peak image will fol= low.

73, Stefan

------=_Part_11850_617421332.1538356548068--