Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dd04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 3046538000090; Thu, 26 Jul 2012 21:45:57 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SuZbV-0001uo-O9 for rs_out_1@blacksheep.org; Fri, 27 Jul 2012 02:44:33 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SuZbU-0001uf-UL for rsgb_lf_group@blacksheep.org; Fri, 27 Jul 2012 02:44:32 +0100 Received: from mail-wg0-f47.google.com ([74.125.82.47]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1SuZbT-0006WL-7U for rsgb_lf_group@blacksheep.org; Fri, 27 Jul 2012 02:44:31 +0100 Received: by wgbfa7 with SMTP id fa7so1836932wgb.28 for ; Thu, 26 Jul 2012 18:44:29 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; bh=7anIPWB5Lf4vjBLTg1dQZ92xmG+x4/CCIK1sVhg8NIE=; b=ZcNXaDwxzKGKuPEuYFjjsF9wZx2T8ITezBa9GmN/AIvSReq2x/PNKoZ0FFbBCGyt6D 2MsqWhwUsa1JgvycttOP5T40wbSNJ7J9QA8og1SmuRotal1U2qZuPT6KkGy8PF4PQhBQ kwe0lbZtT/E3aHY1cisPz53xn8FVRkdjbZCYwu8uOPv73Ltp0xC9iNEG7Q7G1N1bFADL KxTzeUOrD86JCDN1ziFvErkt1E0MXP5t85QOo9BDNxPLHxOj4I5PzyQcQHlT9DA7aUxK OhbWADbaPnwBByDIY7ZALIHCYLukSDmbETAyqbAiQJYeBavudTWGTV9uzUERxwVCUtm1 DVAg== MIME-Version: 1.0 Received: by 10.180.106.137 with SMTP id gu9mr1712643wib.20.1343353469837; Thu, 26 Jul 2012 18:44:29 -0700 (PDT) Received: by 10.194.42.228 with HTTP; Thu, 26 Jul 2012 18:44:29 -0700 (PDT) In-Reply-To: <5011AD16.5000706@iup.uni-heidelberg.de> References: <50113D08.8020407@iup.uni-heidelberg.de> <5011AD16.5000706@iup.uni-heidelberg.de> Date: Thu, 26 Jul 2012 21:44:29 -0400 Message-ID: From: Warren Ziegler To: rsgb_lf_group@blacksheep.org X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Thanks Stefan for the explanation! I knew that it must be possible since you have done it! Vy 73 Warren On Thu, Jul 26, 2012 at 4:48 PM, Stefan Schäfer wrote: > Hello Warren, > > Am 26.07.2012 19:39, schrieb Warren Ziegler: > >> Stefan, >> I imagine that a LF or VLF small vertical is a relatively high-Q >> circuit, how do you manage to keep the kite vertical in resonance and >> matched while the kite bounces around in the wind? >> > Most of the time the kite was quite stable, i.e. the angle and so the C did > not change significantly. The antenna current is stable within a 10% limit. > When the wind was poor in some situations, the kite drops to a lower angle. > Then the falling ERP is rather affected by the lower effective height than > by the changing current. The current (say 1A on 8970 Hz) can easyly drop to > 400 mA when the angle changes from 80 deg to 40 deg. > One method is to compensate this by turning the variometer from time to time > or you can use a working point of the variometer that uses a slightly to low > L. Then the antenna current does not reduce when the kite falls (in certain > limits of course). This is the case because the little generator that i used > (up to 550 W RF power in the best times) can be seen as something like a > constant power source. So if the kite falls then slightly, the working point > moves to the peak of the resonance curve and the rotation speed is somewhat > lowered. It was funny to observe this effect for many hours on the field :-) > But normally the movement of the wire does not strongly change the antenna > current. > > OK? > > > 73, Stefan/DK7FC > [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [74.125.82.47 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (wd2xgj[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 9ca91679b330d65f05d707c2d2b164fe Subject: Re: LF: Kites Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable 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-SCOLL-SCORE: 0:2:491067904:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d291.1 ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d40905011f2d503f1 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Thanks Stefan for the explanation! I knew that it must be possible since you have done it! Vy 73 Warren On Thu, Jul 26, 2012 at 4:48 PM, Stefan Sch=E4fer wrote: > Hello Warren, > > Am 26.07.2012 19:39, schrieb Warren Ziegler: > >> Stefan, >> I imagine that a LF or VLF small vertical is a relatively high-Q >> circuit, how do you manage to keep the kite vertical in resonance and >> matched while the kite bounces around in the wind? >> > Most of the time the kite was quite stable, i.e. the angle and so the C d= id > not change significantly. The antenna current is stable within a 10% limi= t. > When the wind was poor in some situations, the kite drops to a lower angl= e. > Then the falling ERP is rather affected by the lower effective height tha= n > by the changing current. The current (say 1A on 8970 Hz) can easyly drop = to > 400 mA when the angle changes from 80 deg to 40 deg. > One method is to compensate this by turning the variometer from time to t= ime > or you can use a working point of the variometer that uses a slightly to = low > L. Then the antenna current does not reduce when the kite falls (in certa= in > limits of course). This is the case because the little generator that i u= sed > (up to 550 W RF power in the best times) can be seen as something like a > constant power source. So if the kite falls then slightly, the working po= int > moves to the peak of the resonance curve and the rotation speed is somewh= at > lowered. It was funny to observe this effect for many hours on the field = :-) > But normally the movement of the wire does not strongly change the antenn= a > current. > > OK? > > > 73, Stefan/DK7FC > --=20 73 Warren K2ORS WD2XGJ WD2XSH/23 WE2XEB/2 WE2XGR/1