Return-Path: Received: (qmail 20951 invoked from network); 10 Dec 2000 18:30:14 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by extortion.plus.net with SMTP; 10 Dec 2000 18:30:14 -0000 Received: (qmail 24674 invoked from network); 10 Dec 2000 18:32:21 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 10 Dec 2000 18:32:21 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 145BBs-0002tt-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 10 Dec 2000 18:27:16 +0000 Received: from imo-r12.mx.aol.com ([152.163.225.66] helo=imo-r12.mail.aol.com) by post.thorcom.com with esmtp (Exim 3.16 #1) id 145BBr-0002to-00 for rsgb_lf_group@blacksheep.org; Sun, 10 Dec 2000 18:27:15 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from MarkusVester@aol.com by imo-r12.mx.aol.com (mail_out_v28.34.) id l.11.cdb71c0 (3896) for ; Sun, 10 Dec 2000 13:26:29 -0500 (EST) From: MarkusVester@aol.com Message-ID: <11.cdb71c0.276524d4@aol.com> Date: Sun, 10 Dec 2000 13:26:28 EST Subject: LF: LF antenna voltage To: rsgb_lf_group@blacksheep.org MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 8bit X-Mailer: Windows AOL sub 68 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Laurie, on our LF antennas the voltage is almost constant along the wire, so its peak value is simply Up = 1.41 * I_eff / (2 * pi *f * C) ; e.g. with 600pF antenna capacitance and 3 amps, you will get 15.6 kV on 72 kHz, which shouldn't be a problem in dry weather. My thin 137 kHz ant is similar with 1.5 amps into 170 pF, giving 14.6 kV. One of the 1 mm perlon strings once melted when it was attatched to the wire end without any insulator. 73 de Markus