Return-Path: Received: (qmail 20014 invoked from network); 23 Jan 2000 00:35:12 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by grants.core.plus.net.uk with SMTP; 23 Jan 2000 00:35:12 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12CAu3-0000Ky-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 23 Jan 2000 00:29:15 +0000 Received: from mailout06.sul.t-online.de ([194.25.134.19]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12CAu1-0000Kn-00 for rsgb_lf_group@blacksheep.org; Sun, 23 Jan 2000 00:29:13 +0000 Received: from fwd05.sul.t-online.de by mailout06.sul.t-online.de with smtp id 12CAtw-0002u0-00; Sun, 23 Jan 2000 01:29:08 +0100 Received: from (087321565-0001@[193.158.172.229]) by fwd05.sul.t-online.de with smtp id 12CAtp-0vGqXZC; Sun, 23 Jan 2000 01:29:01 +0100 X-Priority: 3 X-MSMail-Priority: Normal From: "Hans-Joachim Brandt" To: rsgb_lf_group@blacksheep.org X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 References: <38856E64.9E096059@phonakcom.ch> Subject: Re: LF: Resonance and Impedance change in the winter season X-Mailer: T-Online eMail 2.3 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 8bit Date: Sun, 23 Jan 2000 01:29:01 +0100 Message-ID: <12CAtp-0vGqXZC@fwd05.sul.t-online.de> X-Sender: 087321565-0001@t-dialin.net Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Toni Baertschi schrieb: > >From HB9ASB, JN36pt > > PS. Actually it is very cold here and my antenna de-tunes from hour to > hour as the soil is freezing deeper and deeper. Not only the resonance > goes higher, the impedance is also changing and it is difficult to > follow this developement with the existing matching circuit. Now, during winter time I can make the same observations. Before I have just experienced small changes in resonance, but now, in the cold, not only resonance changes considerably but also VSWR increases to S = 2 at optimum tune (I am using a 50 ohms feeder cable between PA and LF antenna). Therefore I also have to revise my fine tuning and matching circuitry to cope with these effects. 73 Ha-Jo, DJ1ZB > > > > > > > > >