Return-Path: Received: from mtain-mk03.r1000.mx.aol.com (mtain-mk03.r1000.mx.aol.com [172.29.97.135]) by air-df06.mail.aol.com (v129.4) with ESMTP id MAILINDF063-5ef84d0927322fc; Wed, 15 Dec 2010 15:38:10 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mk03.r1000.mx.aol.com (Internet Inbound) with ESMTP id B7FD3380000DB; Wed, 15 Dec 2010 15:38:08 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PSy5S-0000ca-Dw for rs_out_1@blacksheep.org; Wed, 15 Dec 2010 20:36:34 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PSy5R-0000cR-U8 for rsgb_lf_group@blacksheep.org; Wed, 15 Dec 2010 20:36:33 +0000 Received: from imr-db02.mx.aol.com ([205.188.91.96]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PSy5P-0007sW-0h for rsgb_lf_group@blacksheep.org; Wed, 15 Dec 2010 20:36:33 +0000 Received: from mtaout-da02.r1000.mx.aol.com (mtaout-da02.r1000.mx.aol.com [172.29.51.130]) by imr-db02.mx.aol.com (8.14.1/8.14.1) with ESMTP id oBFKaNE7030228 for ; Wed, 15 Dec 2010 15:36:23 -0500 Received: from White (nrbg-4d073bd8.pool.mediaWays.net [77.7.59.216]) by mtaout-da02.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id 977C2E0000CE for ; Wed, 15 Dec 2010 15:36:20 -0500 (EST) Message-ID: <7EAE83105871446499F92C2AF82C1C5C@White> From: "Markus Vester" To: References: <2D9F1290-9246-4DFD-A0E6-D9D58DEF00AC@numeo.fr> <4D08A0AA.6040408@iup.uni-heidelberg.de> <4D08C0DA.1030007@iup.uni-heidelberg.de> Date: Wed, 15 Dec 2010 21:36:18 +0100 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-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126 Subject: Re: LF: VLF - distances achjeved (Earth loop ERP) Content-Type: multipart/alternative; boundary="----=_NextPart_000_0087_01CB9CA0.1BDD9D00" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.3 required=5.0 tests=HTML_60_70,HTML_MESSAGE, HTML_TAG_EXISTS_TBODY,MISSING_OUTLOOK_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 x-aol-global-disposition: G x-aol-sid: 3039ac1d61874d0927304e0d X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_0087_01CB9CA0.1BDD9D00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable John, Stefan, we could to assign an approximate ERP to Stefan's earth loop experimen= t as well.=20 In July, he measured DHO38 receive voltage on his earlier 280m long ea= rth antenna, which resulted in a return current depth of 29 m at 23.4= kHz. Scaling this by sqrt(f) gives 47 m at 9 kHz, and a loop area of= 28000 m^2 for his new 600 m wire. The radiation resistance of this ea= rth loop is thus approximately 20 microohms. Assuming 0.8 amps (correc= t me if I'm wrong), Stefan would have radiated 13 uW (EMRP) or 23 uW= (ERP) towards North and South. Best regards, Markus (DF6NM) =20 Am 15.12.2010 12:04, schrieb Stefan Sch=E4fer:=20 Hi John, Am 15.12.2010 11:55, schrieb John Rabson:=20 I am writing a piece on VLF for the Cave Radio & Electronics Group= Journal and would like to include distance records. Can people pleas= e confirm that the following information is correct (or not)?=20 Above-ground antennas Hz ERP mW From To km=20 8970 58 Darmstadt Israel/Haifa 2873=20 6470 9 Darmstadt Poland/Warshaw 904=20 5170 5 Darmstadt Poland/Warshaw 904=20 =20 =20 =20 =20 =20 The QTH of SQ5BPF is Washaw. The rest is correct. Earth current antennas Hz TX power W Electrode spacing m From To km=20 8970 250 600 Heidelberg Roschbach 49.6=20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 =20 I did successful tests to Roschbach just on 8970 Hz, not on 6470 and= 5170. The distance is 49.6 km (since my earth antenna QTH is differen= t to the kite antenna QTH). Thanks too. 73, Stefan/DK7FC Thank you.=20 John F5VLF ------=_NextPart_000_0087_01CB9CA0.1BDD9D00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
John, Stefan,
 
we could to assign an approximat= e ERP to=20 Stefan's earth loop experiment as well.
 
In July, he measured D= HO38 receive=20 voltage on his earlier 280m long earth antenna, which result= ed in a=20 return current depth of 29 m at 23.4 kHz. Scaling this by=20 sqrt(f) gives 47 m at 9 kHz, and a loop area of 28000 m^2 for his= new 600=20 m wire. The radiation resistance of this earth loop is thus= =20 approximately 20 microohms. Assuming 0.8 amps (correct me if I'm=20 wrong), Stefan would have radiated 13 uW (EMRP) or 23 uW (ERP)&nb= sp;towards=20 North and South.
 
Best regards,
Markus (DF6NM)  


Am=20 15.12.2010 12:04, schrieb Stefan Sch=E4fer:
Hi=20 John,

Am 15.12.2010 11:55, schrieb John Rabson:=20
I am writing a piece on VLF for the Cave Radio &a= mp; Electronics=20 Group Journal and would like to include distance records.  Ca= n people=20 please confirm that the following information is correct (or not)?= =20


Above-ground=20 antennas


Hz
=
ERP mW
From
To
=
km
=
8970
58
=
Darmstadt
Israel/Haifa
2873
6470
9
<= /TD>
Darmstadt
Poland/Warshaw
904
5170
5
<= /TD>
Darmstadt
Poland/Warshaw
904





The QTH of SQ5BPF= is=20 Washaw. The rest is correct.

Ear= th current antennas

=

Hz
=
TX power W
Electrode spaci= ng=20 m
From
To
=
km
=
8970
250
600
Heidelberg
Roschbach
49.6
















=
I did=20 successful tests to Roschbach just on 8970 Hz, not on 6470 and 5170.= The=20 distance is 49.6 km (since my earth antenna QTH is different to the= kite=20 antenna QTH).

Thanks too.

73, Stefan/DK7FC

Thank you.

John F5VLF


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