Return-Path: Received: from mtain-mg06.r1000.mx.aol.com (mtain-mg06.r1000.mx.aol.com [172.29.96.206]) by air-dd03.mail.aol.com (v129.4) with ESMTP id MAILINDD033-86594d76865e2fb; Tue, 08 Mar 2011 14:41:18 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mg06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2D90738000154; Tue, 8 Mar 2011 14:41:16 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Px2lh-0001gs-Pa for rs_out_1@blacksheep.org; Tue, 08 Mar 2011 19:40:29 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Px2lh-0001gj-DD for rsgb_lf_group@blacksheep.org; Tue, 08 Mar 2011 19:40:29 +0000 Received: from smtpout02.highway.telekom.at ([195.3.96.113] helo=email.aon.at) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Px2lf-0000uU-7N for rsgb_lf_group@blacksheep.org; Tue, 08 Mar 2011 19:40:29 +0000 Received: (qmail 4332 invoked from network); 8 Mar 2011 19:40:20 -0000 Received: from 93-82-0-185.adsl.highway.telekom.at (HELO [192.168.1.101]) ([93.82.0.185]) (envelope-sender ) by smarthub94.highway.telekom.at (qmail-ldap-1.03) with SMTP for ; 8 Mar 2011 19:40:20 -0000 From: Gerhard Hickl To: rsgb_lf_group@blacksheep.org In-Reply-To: <33d07ccc43ec486d83d0d460928f26ad@kabelmail.de> References: <33d07ccc43ec486d83d0d460928f26ad@kabelmail.de> Date: Tue, 08 Mar 2011 20:40:20 +0100 Message-ID: <1299613220.2199.19.camel@gerhard-desktop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: VLF dj8wx on 8970.022Hz Content-Type: text/plain; charset="UTF-8" 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 x-aol-global-disposition: G x-aol-sid: 3039ac1d60ce4d76865c1140 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hello Uwe! Regarding to my experience, the 40kV are real. Considering the high power (anf thus current) you are running, the voltage would be much higher on my 550mH coil. 550mh = 31kOhm at 9000Hz = 3A*31kOhm = 93kV.....luckily I just can manage to get about 0.6A and thus Voltages are lower! Voltages above 10kV are usual when transmitting on VLF and therefore every effort should be taken on insulating the "hot" part of the antenna. 73 OE3GHB Gerhard Am Dienstag, den 08.03.2011, 19:27 +0100 schrieb uwe-jannsen@kabelmail.de: > Hi all, > > > > Im doing some measurements trying to find out how low (high?) the ERP > of my system is. > > > > the test lead of the oscilloscope in use has a resistor of 10Mohm. The > oscilloscope advise text says that I have to multiply the result by > 10. > > OK. I added two other 10Mohm in series multiplyed the result by 1000 > and got 40000Vpp > > using the twentieth of max TX power. 40kV? Is that possible? > > the current from the coile foot into the radials was 0.145A (3 A with > max power). > > I cant measure the Tesla voltage when the power is raised because the > oscilloscope or other > > instruments indicate results without connected to the object under > test. > > > > the station is on the air in mode QRSS3600 on 8970.022Hz since today > 1640UTC. > > > > current into the radials: one Ampere. > > > > who will try to calculate the ERP? > > the aerial in use can be seen at > > > > http://dj8wx-dl.de/hompage500kHz/TX%20equipment.htm > > > > fourth pic on the site. The shown 23m long wire has been lengthened to > 43m. > > > > best regards > > Uwe/dj8wx > > > >