Return-Path: Received: from mtain-ma08.r1000.mx.aol.com (mtain-ma08.r1000.mx.aol.com [172.29.96.16]) by air-de01.mail.aol.com (v129.4) with ESMTP id MAILINDE011-5ea24cc75b223b4; Tue, 26 Oct 2010 18:50:10 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-ma08.r1000.mx.aol.com (Internet Inbound) with ESMTP id 14228380000CB; Tue, 26 Oct 2010 18:50:06 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PAsJW-00007m-Iq for rs_out_1@blacksheep.org; Tue, 26 Oct 2010 23:48:18 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PAsJW-00007d-6b for rsgb_lf_group@blacksheep.org; Tue, 26 Oct 2010 23:48:18 +0100 Received: from mbox2.netikka.net ([213.250.81.203]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PAsJU-0007SZ-Io for rsgb_lf_group@blacksheep.org; Tue, 26 Oct 2010 23:48:18 +0100 Received: from hupu.netikka.net (hupu [172.16.83.91]) by mbox2-feedback.netikka.net (Postfix) with ESMTP id 6FC8621F1D1 for ; Wed, 27 Oct 2010 01:48:10 +0300 (EEST) Received: from imp1.netikka.net (imp1.netikka.net [213.250.85.154]) by hupu.netikka.net (Postfix) with ESMTP id 85ADE4B004B for ; Wed, 27 Oct 2010 01:48:10 +0300 (EEST) Received: from localhost (localhost [127.0.0.1]) by imp1.netikka.net (Postfix) with ESMTP id 47F27495BB9 for ; Wed, 27 Oct 2010 01:48:10 +0300 (EEST) Received: from b31.ip15.netikka.fi (b31.ip15.netikka.fi [94.22.108.31]) by imp.netikka.net (IMP) with HTTP for ; Wed, 27 Oct 2010 01:48:10 +0300 Message-ID: <1288133290.4cc75aaa4322c@imp.netikka.net> Date: Wed, 27 Oct 2010 01:48:10 +0300 From: Paul-Henrik To: rsgb_lf_group@blacksheep.org References: <4CC05B8F.2030406@iup.uni-heidelberg.de> <1237369649.1611432.1287678227104.JavaMail.fmail@mwmweb077> <4CC070EA.30703@iup.uni-heidelberg.de> <4CC1C2EF.8080007@iup.uni-heidelberg.de> <757145.20787.qm@web111905.mail.gq1.yahoo.com> <979620351.2557914.1287853881158.JavaMail.fmail@mwmweb077> <1287855842.4cc31ee2b778a@imp.netikka.net> In-Reply-To: MIME-Version: 1.0 User-Agent: Internet Messaging Program (IMP) 3.2.6 X-Originating-IP: 94.22.108.31 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: VLF: here no results from DK7FC's 8th experiment Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable 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=none 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-sid: 3039ac1d60104cc75b1e260a X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) Hello Roelof, LF Thanks for this information, I will consider this option as my next step= towards better receive sensitivity for future tests. BN73-202 should be possible to obtain here but how about the common mode= choke core material? One would need to acheive an XL of several kohms at such a= low frequency while still keeping the interwinding capacitance at a minimum. BR Paul-Henrik, OH1LSQ Quoting Roelof Bakker : > Hello Paul-Henrik, > > I have build a special mini-whip for Michael Oexner, which uses CAT5 > network cable for RF and DC feed. > It is equipped with an isolating transformer in the mini-whip and antenn= a > interface plus common mode chokes in the DC feedline. > The isolating transformers are obsolete MCL type TT1-6's, which have a > lower roll off of 4 kHz. > > I had a limited supply of TT1-6's and have replaced them with a home mad= e > transformer wound on a Amidon BN-73-202 binocular core. > As far I can see the frequency response is the same. > > Unfortunately I had to go out of town on Saturday and could not > participate in the experiment. > > 73, > Roelof, pa0rdt > >