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 w8UNgjO6014579 for ; Mon, 1 Oct 2018 01:42:46 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1g6lAC-0005uR-VS for rs_out_1@blacksheep.org; Mon, 01 Oct 2018 00:30:12 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1g6lAC-0005uI-CO for rsgb_lf_group@blacksheep.org; Mon, 01 Oct 2018 00:30:12 +0100 Received: from resqmta-ch2-05v.sys.comcast.net ([2001:558:fe21:29:69:252:207:37]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91_59-0488984) (envelope-from ) id 1g6lA8-0001ib-VI for rsgb_lf_group@blacksheep.org; Mon, 01 Oct 2018 00:30:11 +0100 Received: from resomta-ch2-06v.sys.comcast.net ([69.252.207.102]) by resqmta-ch2-05v.sys.comcast.net with ESMTP id 6jhVgx1ZJ4eQ46lA4g0cwI; Sun, 30 Sep 2018 23:30:04 +0000 X-DKIM-Result: Domain=comcast.net Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=q20161114; t=1538350204; bh=e7pIe6x1H0Im5MTunvIWHB3i9IC355l18+5/W09FQ5I=; h=Received:Received:From:To:Subject:Date:Message-ID:MIME-Version: Content-Type; b=O7cpK5FvT51udBKQkHR6sHYn0FSyV1vsexJznSSIiPFfW/rhflPoXPPGKeuamX1bX HzQbfZrWhxxuIjzldI1gsFeUUU+3EFyjromRvekF4KCZtxPtHzY9yn3tru/OoeR/oq idSJJ3b5Xat6xuB6pq4C/+YHe7sbmXf+1LJp4X3ljvba4Xw+VqNEWXWgMchaxvp/Y1 F1TBtH6nL1FQNLonZKIStjezRLSrS1bGehR3OUqjmPiwvoc/XnLQAupRBiP72ltOjh e+gi+uH3QkHEwgVX3cVwcuqLgKjopDiCcZDe5vEY1J1eEZvyZzsUOsyoXX4KYDFNla X0jw5A7TW/rgA== Received: from Owner ([IPv6:2601:140:8500:7f9f:78f6:dd:b547:d008]) by resomta-ch2-06v.sys.comcast.net with ESMTPA id 6lA2gXnPoVExX6lA3gWvNU; Sun, 30 Sep 2018 23:30:03 +0000 From: To: References: <00e801d457a0$f0c456d0$d24d0470$@comcast.net> <166244011c2-1ec5-3af1@webjasstg-vab11.srv.aolmail.net> <013301d4580b$080ef6f0$182ce4d0$@comcast.net> <5BAFE7D6.8050708@posteo.de> In-Reply-To: <5BAFE7D6.8050708@posteo.de> Date: Sun, 30 Sep 2018 19:30:00 -0400 Message-ID: <019501d45915$822b5450$8681fcf0$@comcast.net> MIME-Version: 1.0 X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQF7qH+veFak98DAZFyI0h9scEfVMgHJqGctAjnaUc4BooXuNqWNlMJg Content-Language: en-us X-CMAE-Envelope: MS4wfM9OqPkHWhTf5viVasq/FnuRLKR2FXavoyGxocrtbpiRga0f7sYRTPIdaBIVpdIn8aSnIRc3uX/0n/rhCFfFP/4kSK+hIsnlY66qfKVokrwCd3naWWwF F9Htn+behMHCRSFCGSGT47Y0ru+I4OLuDjpOauKhcM8tkHaGn/MkwspZhNyZdZ0F3WHa2zwbefvQnTeqkOHyPWLL3aLeOaD8JSrpxlKoaOf+82lPonM532Or X-Spam-Score: -0.7 (/) 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: Stefan, Congratulations! A great milestone for many reasons. Amazing to think of far-field at that frequency without tons of antenna; a credit to design, test planning, and test execution. [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [2001:558:fe21:29:69:252:207:37 listed in] [list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (hvanesce[at]comcast.net) -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: b322dc0956bb435e223041a6879534f9 Subject: LF: RE: The next experiment on 970 Hz - Cracked the far field border below 1 kHz Content-Type: multipart/alternative; boundary="----=_NextPart_000_0196_01D458F3.FB19B450" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.1 required=5.0 tests=HTML_30_40,HTML_MESSAGE, NO_REAL_NAME 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 This is a multipart message in MIME format. ------=_NextPart_000_0196_01D458F3.FB19B450 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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 character 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 = away from a transmitting loop antenna 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 wavelengths = 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 = polarization, near 0.18 wavelengths (an interesting distance on its own) = from a ground-loop transmitting 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@blacksheep.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 current 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 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. However, = as i routinely calculated the SNR from the N-S loop i got a surprising = SNR of 13.03 dB in 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 vertical 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 = (which actually points rather to 30/210 deg) and got the following = result (including 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 -f970.01 | 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 = 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 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.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 it maybe mean a steep reflexion on the ionosphere, so that = the E field antenna 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. 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 ------=_NextPart_000_0196_01D458F3.FB19B450 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

Stefan,

 

Congratulations! A great milestone for many = reasons.

 

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

 

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

 

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.

 

In free space the electric field at a receiving antenna 0.18 = wavelengths away from a transmitting loop antenna 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 wavelengths = 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 = polarization, near 0.18 wavelengths (an interesting distance on its own) = from a ground-loop transmitting antenna at 970 = Hz?

 

Another fascinating realm now opened, much = appreciated.

73,

Jim AA5BW

 

 

*(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)

 

 

=C2=A0

 

From: owner-rsgb_lf_group@blacksheep.org = [mailto:owner-rsgb_lf_group@blacksheep.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

 

Hi ULF, =

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 current 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 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. However, as i routinely = calculated the SNR from the N-S loop i got a surprising SNR of 13.03 dB = in 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 vertical 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 (which actually points rather to 30/210 = deg) and got the following result (including 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 -f970.01 | 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 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 parameters for a higher SNR and try to = filter out the short QRM from the charger.

So now, why does the = E field produce such bad results? At = http://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 it maybe mean a steep reflexion on the ionosphere, so that = the E field antenna 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. 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

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