X-GM-THRID: 1229627323861453001 X-Gmail-Labels: rsgb lf Delivered-To: daveyxm@gmail.com Received: by 10.115.73.6 with SMTP id a6cs191153wal; Wed, 28 Feb 2007 03:59:58 -0800 (PST) Received: by 10.67.29.12 with SMTP id g12mr504123ugj.1172663997968; Wed, 28 Feb 2007 03:59:57 -0800 (PST) Return-Path: Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mx.google.com with ESMTP id e34si482761ugd.2007.02.28.03.59.55; Wed, 28 Feb 2007 03:59:57 -0800 (PST) Received-SPF: neutral (google.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1HMNL3-0004wo-M5 for rs_out_1@blacksheep.org; Wed, 28 Feb 2007 11:51:17 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1HMNL2-0004wf-TL for rsgb_lf_group@blacksheep.org; Wed, 28 Feb 2007 11:51:16 +0000 Received: from alias14.ihug.co.nz ([203.96.222.24]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1HMNKy-000094-E7 for rsgb_lf_group@blacksheep.org; Wed, 28 Feb 2007 11:51:16 +0000 Received: from ironport2.ihug.co.nz [203.109.254.20] by alias14.ihug.co.nz with esmtp (Exim 3.36 #1 (Debian)) id 1HMNKr-0002kO-00; Thu, 01 Mar 2007 00:51:05 +1300 Received: from 203-109-220-224.bliink.ihug.co.nz (HELO athlon1200) ([203.109.220.224]) by ironport2.ihug.co.nz with SMTP; 01 Mar 2007 01:25:17 +1300 X-Ironport-Seen: Yes Message-ID: <000001c75b2e$d0b84930$7900a8c0@athlon1200> From: "Dave Brown" To: , "Discussion of the Lowfer \(US, European, & UK\) and MedFer bands" References: <009c01c755e8$85abf040$ea196a58@wgt01> <01b201c755f2$3e9afde0$7900a8c0@athlon1200> Date: Thu, 1 Mar 2007 00:51:35 +1300 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: Protecting E probe antennas in near field of LF TX antennas Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response Content-Transfer-Encoding: 7bit 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 Status: O X-Status: X-Keywords: X-UID: 2518 Has anyone done anything along the lines of the subject line using a mechanical switch/relay arrangement? I expect that any electronic method would add considerably to the capacitance from the probe 'antenna' to ground so the best option would seem to be to use something like the mechanical arrangement in the old Dow-Key coax relays that had the 'isolated' receive side contact. This will require a relay of some sort in the E probe that operates to remove the protective earth only when on receive. I'm still mulling over the best mechanical arrangement to implement this scheme-all ideas most welcome. 73 Dave, ZL3FJ