Return-Path: Received: from mtain-me05.r1000.mx.aol.com (mtain-me05.r1000.mx.aol.com [172.29.96.141]) by air-dc03.mail.aol.com (v129.10) with ESMTP id MAILINDC033-864f4da8417bb4; Fri, 15 Apr 2011 09:00:43 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-me05.r1000.mx.aol.com (Internet Inbound) with ESMTP id C8F6B380013EF; Fri, 15 Apr 2011 08:59:37 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QAibb-0001Jq-V2 for rs_out_1@blacksheep.org; Fri, 15 Apr 2011 13:58:35 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QAibb-0001Jh-FT for rsgb_lf_group@blacksheep.org; Fri, 15 Apr 2011 13:58:35 +0100 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QAibZ-0007P8-Vy for rsgb_lf_group@blacksheep.org; Fri, 15 Apr 2011 13:58:35 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id p3FCwWDq027563 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 15 Apr 2011 14:58:32 +0200 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id p3FCwWr3013482 for ; Fri, 15 Apr 2011 14:58:32 +0200 Message-ID: <4DA840AF.6040507@iup.uni-heidelberg.de> Date: Fri, 15 Apr 2011 14:57:19 +0200 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <618180.72059.qm@web28509.mail.ukl.yahoo.com> In-Reply-To: <618180.72059.qm@web28509.mail.ukl.yahoo.com> X-Spam-Score: 1.6 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: VLF - vertical probe measurements Content-Type: multipart/alternative; boundary="------------070204080303030204020109" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30,HTML_MESSAGE, HTML_TAG_EXISTS_TBODY 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-global-disposition: G x-aol-sid: 3039ac1d608d4da841391b90 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --------------070204080303030204020109 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello Chris, I would expect a sqare law relationship as well since the probe is a capacitive divider and thus the voltage should be directly proportional to the antennas voltage. And this rises with sqrt(2) x the power... 73, Stefan Am 15.04.2011 14:40, schrieb Chris Osborn: > LF, > Acting on advice I have installed a whip aerial (probe) on top of a > mast at the boundary of my property. > This is in order to monitor my VLF transmissions and to provide a > reference level for any system improvements. > I noticed that the probe's pick-up voltage is directly proportional > to my PA's supply current. > Assuming that the PA efficiency doesn't change drastically with > current then would I be correct in assuming that the probe's voltage > is _directly proportional_ to the radiated power? > I was expecting a square law relationship . . > 73 > Chris G3XIZ > --------------070204080303030204020109 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello Chris,

I would expect a sqare law relationship as well since the probe is a capacitive divider and thus the voltage should be directly proportional to the antennas voltage. And this rises with sqrt(2) x the power...


73, Stefan


Am 15.04.2011 14:40, schrieb Chris Osborn:
LF,
 
Acting on advice I have installed a whip aerial (probe) on top of a mast at the boundary of my property.
This is in order to monitor my VLF transmissions and to provide a reference level for any system improvements.
 
I noticed that the probe's pick-up voltage is directly proportional to my PA's supply current.
Assuming that the PA efficiency doesn't change drastically with current then would I be correct in assuming that the probe's voltage is directly proportional to the radiated power?
 
I was expecting a square law relationship . .
 
73
Chris G3XIZ
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