Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dl05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 12DA4380000E8; Sun, 1 Apr 2012 14:11:25 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SEPE3-0005rI-1x for rs_out_1@blacksheep.org; Sun, 01 Apr 2012 19:10:03 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SEPE2-0005r9-E3 for rsgb_lf_group@blacksheep.org; Sun, 01 Apr 2012 19:10:02 +0100 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1SEPE1-0007WR-06 for rsgb_lf_group@blacksheep.org; Sun, 01 Apr 2012 19:10:02 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id q31I9xG4030934 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 1 Apr 2012 20:09:59 +0200 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id q31I9xRk023201; Sun, 1 Apr 2012 20:09:59 +0200 Message-ID: <4F7899DA.8050400@iup.uni-heidelberg.de> Date: Sun, 01 Apr 2012 20:09:30 +0200 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org CC: Uwe Jannsen References: In-Reply-To: X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: 8.970Khz Content-Type: multipart/alternative; boundary="------------010908020509030705040906" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=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 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:431450592:93952408 x-aol-sid: 3039ac1d4ad34f789a4d3a4f X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. --------------010908020509030705040906 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi Henny, Uwe, VLF, Yesterday i did some tests with an active E field antenna in the forest. I used my normal VLF receive antenna design. First i didn't expect much since it is said that there are little chances to receive anything with an E field antenna in the forest at VLF but i got excellent results! DHO38 easily reached 50 dN S/N. The antenna was hung up 2m above the ground to a branch of a > 20m tree. A small 12V battery was used for the supply and i took a recording of about 10 minutes. In a previous test i had QRM coming from the netbook's screen but yesterday i added a single copper earth rod, 20 cm stuck into the soil. Now the QRM was completely gone and the levels rised 1 or 2 dB. Now i want to try if i can receive your transmission Henny and Uwe, if you have the chance to transmit tomorrow between 8 UTC until the late afternoon? The longer the better. It is exciting how clean the band looks there and i really want to have a permanent remote link to my grabber PC. These are the pre tests... Will you be on air tomorrow? :-) As an additional test i want to add a switch into my antenna which allows to disable the high pass RC part. I will then see the difference and who knows, maybe i can receive the ZEVS on 82 Hz. At least i want to do a recording of > 1 hour. That is such a fascinating WX here! I love it. Also i want to do a new VLF transmission test with the small LOPT transformer from an old TV. It became wet during the last test and then i had a flash over. Maybe it is damaged but maybe not. If not, i will transmit at 8972 Hz or so and try to decode a WOLF10 signal on VLF. I also ordered some audio transformers in different winding ratios. A galvanic decoupling, optimal matching to the soundcard, first using a 4:1 and then a 1:10 xfmr with a local ground between the transformers may help to get a lower noise floor on my 2 orthogonal VLF loops which generate the signals for the CDF VLF grabber at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html 73, Stefan/DK7FC Am 01.04.2012 10:34, schrieb henny van elst: > Gm LF, > the tx is on,8.970 Khz 450 mA antenna current > henny pa3cpm > 73's --------------010908020509030705040906 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi Henny, Uwe, VLF,

Yesterday i did some tests with an active E field antenna in the forest. I used my normal VLF receive antenna design. First i didn't expect much since it is said that there are little chances to receive anything with an E field antenna in the forest at VLF but i got excellent results! DHO38 easily reached 50 dN S/N. The antenna was hung up 2m above the ground to a branch of a > 20m tree. A small 12V battery was used for the supply and i took a recording of about 10 minutes. In a previous test i had QRM coming from the netbook's screen but yesterday i added a single copper earth rod, 20 cm stuck into the soil. Now the QRM was completely gone and the levels rised 1 or 2 dB.

Now i want to try if i can receive your transmission Henny and Uwe, if you have the chance to transmit tomorrow between 8 UTC until the late afternoon? The longer the better. It is exciting how clean the band looks there and i really want to have a permanent remote link to my grabber PC. These are the pre tests...

Will you be on air tomorrow? :-)

As an additional test i want to add a switch into my antenna which allows to disable the high pass RC part. I will then see the difference and who knows, maybe i can receive the ZEVS on 82 Hz. At least i want to do a recording of  > 1 hour. That is such a fascinating WX here! I love it.

Also i want to do a new VLF transmission test with the small LOPT transformer from an old TV. It became wet during the last test and then i had a flash over. Maybe it is damaged but maybe not. If not, i will transmit at 8972 Hz or so and try to decode a WOLF10 signal on VLF.

I also ordered some audio transformers in different winding ratios. A galvanic decoupling, optimal matching to the soundcard, first using a 4:1 and then a 1:10 xfmr with a local ground between the transformers may help to get a lower noise floor on my 2 orthogonal VLF loops which generate the signals for the CDF VLF grabber at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html

73, Stefan/DK7FC



Am 01.04.2012 10:34, schrieb henny van elst:
Gm LF,
the tx is on,8.970 Khz 450 mA antenna current
henny pa3cpm
73's
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