Return-Path: Received: (qmail 19442 invoked from network); 2 Feb 2000 06:31:37 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by teachers.core.plus.net.uk with SMTP; 2 Feb 2000 06:31:37 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12FtEP-0003XU-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 02 Feb 2000 06:25:37 +0000 Received: from mta3-rme.xtra.co.nz ([203.96.92.13]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12FtEN-0003XP-00 for rsgb_lf_group@blacksheep.org; Wed, 02 Feb 2000 06:25:36 +0000 Received: from [202.27.178.153] by mta3-rme.xtra.co.nz (InterMail v4.01.01.00 201-229-111) with SMTP id <20000202062455.MUMS3144.mta3-rme@[202.27.178.153]> for ; Wed, 2 Feb 2000 19:24:55 +1300 X-Priority: 3 X-MSMail-Priority: Normal Message-ID: <3897CCC5.533A@xtra.co.nz> Date: Wed, 02 Feb 2000 19:20:53 +1300 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 From: "vernall" X-Mailer: Mozilla 3.01C-XTRA (Win95; I) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: Change of ground resistance due to frozen ground References: <12FesM-0Y9MaOC@fwd07.sul.t-online.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Hans-Joachim Brandt wrote: > Besides just noting the change It would have been interesting, of course, to > find out into what direction the ground resistance has changed. On one of the > last cold days and before the snow had disappeared I checked it with a resistive > bridge to find that the total feed point resistance of my antenna (when tuned to > resonance) had decreased from 100 ohms down to 60 ohms!!! I do not have a reference at hand to quote a definitive response, but my recollection of ground parameter data is that frozen ground is "bad news" for ground wave loss, as is fresh water. Your measured result is the other way round. I will try to find a text book reference on frozen ground losses versus unfrozen. By the way, the temperate climate here in Wellington, New Zealand involves a few frosts in the winter but no frozen ground as such, so I have not experienced the type of conditions that Hans-Joachim is more familiar with. 73, Bob ZL2CA