Return-Path: X-Spam-DCC: paranoid 1169; 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=-2.5 required=5.0 tests=BAYES_00,HTML_50_60, HTML_MESSAGE autolearn=unavailable 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 s95MTIx7005329 for ; Mon, 6 Oct 2014 00:29:18 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1XauEY-0003eE-1C for rs_out_1@blacksheep.org; Sun, 05 Oct 2014 23:24:54 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1XauEX-0003e5-J9 for rsgb_lf_group@blacksheep.org; Sun, 05 Oct 2014 23:24:53 +0100 Received: from omr-m06.mx.aol.com ([64.12.143.80]) by relay1.thorcom.net with esmtps (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.82) (envelope-from ) id 1XauER-0002fR-DI for rsgb_lf_group@blacksheep.org; Sun, 05 Oct 2014 23:24:52 +0100 Received: from mtaout-mcb01.mx.aol.com (mtaout-mcb01.mx.aol.com [172.26.50.173]) by omr-m06.mx.aol.com (Outbound Mail Relay) with ESMTP id 8BCFB7000008D for ; Sun, 5 Oct 2014 18:24:44 -0400 (EDT) Received: from White (unknown [95.91.239.181]) by mtaout-mcb01.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id D4EDF3800009B for ; Sun, 5 Oct 2014 18:24:43 -0400 (EDT) Message-ID: <2B9B25F1889740D2955FAD5AFF58783D@White> From: "Markus Vester" To: References: <621ECFC5FFD44C5989A1DA8C7DE6D149@AGB> <542DB6ED.1050101@psk31.plus.com> <0ED8E8831B5B4AF7B303B9D722D436B0@AGB> <542ED037.5020506@psk31.plus.com> <5431727C.3040406@psk31.plus.com> <54317AAA.90402@psk31.plus.com> <5431A0DB.80403@psk31.plus.com> <5431C102.6070007@gmail.com> <5431C1BC.3050208@gmail.com> Date: Mon, 6 Oct 2014 00:24:47 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 12.0.1606 X-MimeOLE: Produced By Microsoft MimeOLE V12.0.1606 x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20140625; t=1412547884; bh=jjMWjWIupyLq4oOqA3IXfuAdnN6sLgUmSbhUZ7D8s38=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=FfmXINrO4G4OlFNb5sdFFWO/XC5Sn4RCA0wku4Zo0fdQHXD3n5H0D+Vl9v+r6mGQ0 0mNrPtX1rRfH0YXOSK/auMN6ql/AswHX6miU0oHjcggVy3rQu2UouffJzjxZiQMH1h +cp7+GvrmYvO0UTGjsKKVXvbodU7YrA6+VKy/FrE= x-aol-sid: 3039ac1a32ad5431c52b1a3a X-AOL-IP: 95.91.239.181 X-Scan-Signature: b99b9f5ebb2905dfac0746d3f825052c Subject: Re: LF: Re: Schumann in my garden Content-Type: multipart/alternative; boundary="----=_NextPart_000_0010_01CFE0FB.EF6C77B0" 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 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 675 Dies ist eine mehrteilige Nachricht im MIME-Format. ------=_NextPart_000_0010_01CFE0FB.EF6C77B0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Stefan, very fine result, well worth the effort! 73, Markus From: DK7FC=20 Sent: Monday, October 06, 2014 12:10 AM To: rsgb_lf_group@blacksheep.org=20 Subject: LF: Re: Schumann in my garden PS: Another link :-) The file = https://dl.dropboxusercontent.com/u/19882028/VLF/VLF%20Garten%20in%20T%20= Antenne%2005102014_2nd.WAV (576 MB) You can test your sound system by = listening to the 16 2/3 Hz stuff and ELF sferics :-) Am 06.10.2014 00:06, schrieb DK7FC:=20 Hi ELF und sub-ELF fans,=20 I have to report about very good success on reception in the ELF and = sub-ELF range. This evening arround 16 UTC i successfully received 5 = Schumann resonances with my T antenna in the garden in 8m above ground, = 400m outside the city. I significantly improved the circuit:=20 Higher input resistance, now 100 MOhm Lower cut off frequency using a 3 stage LPF arround 3 kHz also a lower cuf off frequency of the high pass now below 10 Hz Removed the electronic parts from the breadboard and re-soldered them = on a copper board. This was essential! because there were undefined = conducting layers on the breadboard which affected the working point of = the JFET. New preamp: = https://dl.dropboxusercontent.com/u/19882028/VLF/20141005_162621.jpg New schematic: = https://dl.dropboxusercontent.com/u/19882028/VLF/DK7FC%20ELF%20preamp%20V= 2.jpg Results (shown without sferic blanking) wideband 0...24 kHz: = https://dl.dropboxusercontent.com/u/19882028/VLF/NewELF_wide_10s_1.46HzFF= T.png also showing the frequency response of the circuit 0...1 kHz: = https://dl.dropboxusercontent.com/u/19882028/VLF/NewELF_0to1kHz_10s_1.46H= zFFT.png 0...55 Hz: = https://dl.dropboxusercontent.com/u/19882028/VLF/0...55Hz_5sperdiv_45mHzF= FT_garden3rd.png = ZEVS:https://dl.dropboxusercontent.com/u/19882028/VLF/ZEVS_garden3rd.png = (not so strong this time. QRN?) What about these sferics below 2 kHz? Is it normal that they are so = strong? Or is it a technical problem? Can i improve the situation by = harder attenuating the spectrum above 2 kHz? At least this is what i = want to try. Next ideas for improving the SNR of ZEVS and Schumann: Increasing the R of the LPF to 2.2...3.3 MOhm Maybe trying 1 GOhm for biasing the JFETs gate to 6V Improving the insulation of the antenna feeds (simple cord now, = without ceramic between). Trying to rise the antenna 1 meter Fixing the feed point by a ceramic insulator 73, Stefan/DK7FC ------=_NextPart_000_0010_01CFE0FB.EF6C77B0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Stefan,
 
very fine result, well worth the=20 effort!
 
73, Markus

From: DK7FC
Sent: Monday, October 06, 2014 12:10 AM
Subject: LF: Re: Schumann in my garden

PS:=20 Another link :-)  The file https://dl.dropboxusercontent.com/u/1= 9882028/VLF/VLF%20Garten%20in%20T%20Antenne%2005102014_2nd.WAV=20 (576 MB) You can test your sound system by listening to the 16 2/3 Hz = stuff and=20 ELF sferics :-)

Am 06.10.2014 00:06, schrieb DK7FC:=20
Hi ELF = und sub-ELF=20 fans,

I have to report about very good success on reception in = the=20 ELF  and sub-ELF range. This evening arround 16 UTC i = successfully=20 received 5 Schumann resonances with my T antenna = in the=20 garden in 8m above ground, 400m outside the city.

I = significantly=20 improved the circuit:

Higher input resistance, now 100 = MOhm
Lower=20 cut off frequency using a 3 stage LPF arround 3 kHz
also a lower = cuf off=20 frequency of the high pass now below 10 Hz
Removed the electronic = parts=20 from the breadboard and re-soldered them on a copper board. This was=20 essential! because there were undefined conducting layers on the = breadboard=20 which affected the working point of the JFET.

New preamp: https://dl.dropboxusercontent.com/u/19882028/VLF= /20141005_162621.jpg
New=20 schematic: https://dl.dropboxusercontent.com/u/19882028/VLF= /DK7FC%20ELF%20preamp%20V2.jpg

Results=20 (shown without sferic blanking)
wideband 0...24 kHz: https://dl.dropboxusercontent.com/u/19882028/VLF= /NewELF_wide_10s_1.46HzFFT.png =20 also showing the frequency response of the circuit
0...1 kHz: https://dl.dropboxusercontent.com/u/19882028/VLF= /NewELF_0to1kHz_10s_1.46HzFFT.png
0...55=20 Hz: https://dl.dropboxusercontent.com/u/19882028/VLF= /0...55Hz_5sperdiv_45mHzFFT_garden3rd.png
ZEVS:https://dl.dropboxusercontent.com/u/19882028/VLF= /ZEVS_garden3rd.png =20 (not so strong this time. QRN?)

What about these sferics below = 2 kHz?=20 Is it normal that they are so strong? Or is it a technical problem? = Can i=20 improve the situation by harder attenuating the spectrum above 2 kHz? = At least=20 this is what i want to try.


Next ideas for improving the = SNR of=20 ZEVS and Schumann:
Increasing the R of the LPF to 2.2...3.3 = MOhm
Maybe=20 trying 1 GOhm for biasing the JFETs gate to 6V
Improving the = insulation of=20 the antenna feeds (simple cord now, without ceramic = between).
Trying to=20 rise the antenna 1 meter
Fixing the feed point by a ceramic=20 insulator

73, = Stefan/DK7FC


------=_NextPart_000_0010_01CFE0FB.EF6C77B0--