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 w9SFbJTu012953 for ; Sun, 28 Oct 2018 16:37:21 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1gGn4d-0008DC-4K for rs_out_1@blacksheep.org; Sun, 28 Oct 2018 15:33:55 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1gGn4c-0008D3-NN for rsgb_lf_group@blacksheep.org; Sun, 28 Oct 2018 15:33:54 +0000 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 1gGn4a-0006hS-ME for rsgb_lf_group@blacksheep.org; Sun, 28 Oct 2018 15:33:53 +0000 Received: from resomta-ch2-05v.sys.comcast.net ([69.252.207.101]) by resqmta-ch2-05v.sys.comcast.net with ESMTP id GmdtgfCzY7FSQGn4UgPUva; Sun, 28 Oct 2018 15:33:46 +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=1540740826; bh=wF+dkNwAIgPVqqX0JsoQ6emguaFr49mGGKgJjZTrmFI=; h=Received:Received:From:To:Subject:Date:Message-ID:MIME-Version: Content-Type; b=LxTK602yMX/M49/MA2/izL6kj8dIVWUyoBdDhYa85zlUnZ8D5DcZTOhUGEcZgxX69 ae8i/klb+sFJgmF/9P/CpxeKGXGiQGDhdsFRMZvLxvHLhmsX9HTfNYnPinz/C0tME8 8urj+tI3hRUC9B/pt5TMelgBL20+w6OWoXYtVeFRBJMbT/B3exaAodE8I1XKxHdVl6 gBJUzDsBpDGpiB97FsqinUHQnFhGNFQfFVB0CV2ezjF999/MWcs+EdZozLAB1AoigW PvkSAVt9crgq5RFCGWuLUQsggn2dYZuIBH4qIiexDFEwIua7PyvmVyG47PI7hnH+V7 hjWUUfr0yUp7g== Received: from Owner ([166.170.45.51]) by resomta-ch2-05v.sys.comcast.net with ESMTPA id Gn4LgFiNhA9pcGn4NgPTGn; Sun, 28 Oct 2018 15:33:44 +0000 From: To: References: <5BD44BEA.2070409@posteo.de> <5BD5C968.6020005@posteo.de> In-Reply-To: <5BD5C968.6020005@posteo.de> Date: Sun, 28 Oct 2018 11:33:26 -0400 Message-ID: <03c401d46ed3$9b4c9830$d1e5c890$@comcast.net> MIME-Version: 1.0 X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQHHJl2Tna5vi/5rcBQjCdkIeuaJsAGEJdRlArlTsoylLWXIkA== Content-Language: en-us X-CMAE-Envelope: MS4wfNgihuW7SZ2PVY/yRI9u11imF6cRcEgIvQv3Y042VJxxRtQ9flpu7A9emEnWNhQJ/ztblT6QG6zUxLbEV/2iUWkEjyr43Y/0oFRBW6z3ERJrg16gvx9s V4n9zLfVxxRh5AuUhBGXvhdvYhSuCGlyeuGWO0xKAygq6KdKrJ6pXcbn 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 on another excellent milestone; opening up fascinating new spectral territory with EbNaut links at 970 Hz and 829.9 Hz. Your comments regarding 470 Hz and even perhaps 270 Hz add to the excitement. Propagation should be fairly stable there, compared to frequencies near 2 kHz, but your experiments may the best indicators. [...] 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 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (hvanesce[at]comcast.net) 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_KAM_HTML_FONT_INVALID BODY: Test for Invalidly Named or Formatted Colors in HTML 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 94a3ffcd3903efbf0b2b811b1b1cc0bf Subject: RE: ULF: EbNaut message attempt at 829.9 Hz Content-Type: multipart/alternative; boundary="----=_NextPart_000_03C5_01D46EB2.143AF830" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.2 required=5.0 tests=HTML_30_40,HTML_FONT_BIG, 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_03C5_01D46EB2.143AF830 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Stefan, =20 Congratulations on another excellent milestone; opening up fascinating = new spectral territory with EbNaut links at 970 Hz and 829.9 Hz. =20 Your comments regarding 470 Hz and even perhaps 270 Hz add to the = excitement. Propagation should be fairly stable there, compared to = frequencies near 2 kHz, but your experiments may the best indicators. =20 I wonder if a different type of lightning cancellation would be helpful = at these lower frequencies. Below 2 kHz lightning noise dominates and = grows with decreasing frequency until ~ 1 Hz where micropulsations = dominate. For frequencies near and below 1 Hz some micropulsation = cancellation can be easily achieved. For frequencies 5 kHz and higher a = fair amount of lightning cancellation can be readily achieved in many = scenarios. But I wonder if a different type of lightning noise = cancellation might be helpful at frequencies near and below 1 kHz, and = particularly at and near SLF frequencies where (a) natural noise is = dominated by lightning, (b) time between strokes is closer to the period = of the desired signal (rendering blanking less effective), and (c) long = sferic tails yield a different character to the temporal signature being = canceled. =20 Looking forward to your continuing explorations! =20 73, =20 Jim AA5BW =20 =20 From: owner-rsgb_lf_group@blacksheep.org = [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of DK7FC Sent: Sunday, October 28, 2018 10:36 AM To: rsgb_lf_group@blacksheep.org; Renato Romero Subject: Re: ULF: EbNaut message attempt at 829.9 Hz =20 ULF, ...post-processing completed. It was a rather noisy day, which required = different blanker and antenna mixing settings. At first i used the same = settings like in the recent message at 970 Hz and reached an SNR of just = 9.52 dB. That seemed to far away from the necessary level. Tuning the = levels helped to reach > 13 dB. Then, adding a small portion of the = signal of the N-S loop rised the SNR by 2 dB. A clear and comfortable = decode. Capture attached, showing the signal processing chain and EbNaut decode. That's a 4 character message transfer on 829.9 Hz, the 361 km band! :-) = I never thought to come down so deeply, not even one year ago. Next? Time to try really low frequencies! ;-) Next stop is at 470 Hz, or = 638 km wavelength. Already considering SLF at 270 Hz! All that will be = in the near field from now on, but anyway exciting for me. 73, Stefan Am 27.10.2018 13:28, schrieb DK7FC:=20 Dear ULF friends,=20 Since 11 UTC, i'm attempting to transfer an EbNaut message into the far = field at 829.9 Hz. The antenna current is 1.83 A, blown into my 900m = spaced earth electrode antenna. TX power is 320 W.=20 At the given distance between my TX and RX antennas, 57.6 km, this is = the lowest frequency in the far field. I'm trying: f =3D 829.9 Hz Start time: 27.OCT.2018 11:00 UTC Symbol period: 10 s Characters: 4 CRC bits: 18 Coding 16K21A Antenna current: 1.8 A Duration: 02:45:20 [hh:mm:ss] If the noise background is as low as in the recent 5 character message = at 970 Hz, i will have a spare of 3 dB for a decode, so i am quite = optimistic. If successful, it will be a new record for the lowest frequency for a = message generated/received in the far field, by amateurs. Quite cold here! The notebook is standing on the roof of my old car = while writing this email. Now i have to wait and enjoy the nature here :-) 73, Stefan PS: Since a few days i'm archiving/monitoring the E field ELF...VLF = stream of Renato Romero, IK1QFK. It is unlikely but i will see if he got = the message at a significant SNR... ------=_NextPart_000_03C5_01D46EB2.143AF830 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable

Stefan,

 

Congratulations on another excellent milestone; opening up = fascinating new spectral territory with EbNaut links at 970 Hz and 829.9 = Hz.

 

Your comments regarding 470 Hz and even perhaps 270 Hz add to the = excitement. Propagation should be fairly stable there, compared to = frequencies near 2 kHz, but your experiments may the best = indicators.

 

I wonder if a different type of lightning cancellation would be = helpful at these lower frequencies. Below 2 kHz lightning noise = dominates and grows with decreasing frequency until ~ 1 Hz where = micropulsations dominate. For frequencies near and below 1 Hz some = micropulsation cancellation can be easily achieved. For frequencies 5 = kHz and higher a fair amount of lightning cancellation can be readily = achieved in many scenarios. But I wonder if a different type of = lightning noise cancellation might be helpful at frequencies near and = below 1 kHz, and particularly at and near SLF frequencies where (a) = natural noise =C2=A0is dominated by lightning, (b) time between strokes = is closer to the period of the desired signal (rendering blanking less = effective), and (c) long sferic tails yield a different character to the = temporal signature being canceled.

 

Looking forward to your continuing = explorations!

 

73,

 

Jim AA5BW =C2=A0

 

From: owner-rsgb_lf_group@blacksheep.org = [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of = DK7FC
Sent: Sunday, October 28, 2018 10:36 = AM
To: rsgb_lf_group@blacksheep.org; Renato = Romero
Subject: Re: ULF: EbNaut message attempt at 829.9 = Hz

 

ULF,

...post-processing completed. It was a = rather noisy day, which required different blanker and antenna mixing = settings. At first i used the same settings like in the recent message = at 970 Hz and reached an SNR of just 9.52 dB. That seemed to far away = from the necessary level. Tuning the levels helped to reach > 13 dB. = Then, adding a small portion of the signal of the N-S loop rised the SNR = by 2 dB. A clear and comfortable decode.

Capture attached, = showing the signal processing chain and EbNaut decode.

That's a 4 = character message transfer on 829.9 Hz, the 361 km band! :-)  I = never thought to come down so deeply, not even one year = ago.

Next? Time to try really low frequencies! ;-) Next stop is = at 470 Hz, or 638 km wavelength. Already considering SLF at 270 Hz! All = that will be in the near field from now on, but anyway exciting for = me.

73, Stefan


Am 27.10.2018 13:28, schrieb DK7FC: =

Dear ULF friends,

Since 11 = UTC, i'm attempting to transfer an EbNaut message into the far field at = 829.9 Hz. The antenna current is 1.83 A, blown into my 900m spaced earth = electrode antenna. TX power is 320 W.
At the given distance between = my TX and RX antennas, 57.6 km, this is the lowest frequency in the far = field.
I'm trying:

f =3D 829.9 Hz
Start time: = 27.OCT.2018  11:00 UTC
Symbol period: 10 s
Characters: = 4
CRC bits: = 18
Coding 16K21A
Antenna current: 1.8 A
Duration: = 02:45:20 [hh:mm:ss]

If the noise background is as low as in = the recent 5 character message at 970 Hz, i will have a spare of 3 dB = for a decode, so i am quite optimistic.

If successful, it will be = a new record for the lowest frequency for a message generated/received = in the far field, by amateurs.

Quite cold here! The notebook is = standing on the roof of my old car while writing this email.
Now i = have to wait and enjoy the nature here :-)

73, = Stefan


PS: Since a few days i'm archiving/monitoring the E = field ELF...VLF stream of Renato Romero, IK1QFK. It is unlikely but i = will see if he got the message at a significant = SNR...

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