Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dk06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 2A2263800008A; Fri, 23 Dec 2011 12:33:43 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Re8T3-00044r-DJ for rs_out_1@blacksheep.org; Fri, 23 Dec 2011 16:59:37 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Re8T2-00044i-US for rsgb_lf_group@blacksheep.org; Fri, 23 Dec 2011 16:59:36 +0000 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Re8T1-0002DB-HD for rsgb_lf_group@blacksheep.org; Fri, 23 Dec 2011 16:59:36 +0000 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 pBNGxYTu026253 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 23 Dec 2011 17:59:35 +0100 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 pBNGxZCd019715 for ; Fri, 23 Dec 2011 17:59:35 +0100 Message-ID: <4EF4B307.2010609@iup.uni-heidelberg.de> Date: Fri, 23 Dec 2011 17:57:43 +0100 From: =?ISO-8859-15?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: <4EF3689B.1030902@iup.uni-heidelberg.de> <805AC05E834C4F7DA019C36A04013479@JimPC> In-Reply-To: <805AC05E834C4F7DA019C36A04013479@JimPC> X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: Re: Automatic Variometer adjustment at DK7FC Content-Type: text/plain; charset=ISO-8859-15; format=flowed 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-SCOLL-SCORE: 0:2:472406112:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1db40a4ef4bb773543 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Jim, Another thought: Am 23.12.2011 12:17, schrieb James Moritz: > [...] I guess the inertia of the motor and gearbox will produce some > hysteresis, moving the variometer to a very slightly over-adjusted > position after the motor drive is removed, which will also help to > prevent the system continuously searching around the correct tuning > point.[...] This effect can be compensated by choosing the dead band treshold value. Then the motor gets stopped a bit before the resonance point and will exactly land on it. As good as having an infinitesimal small dead band ;-) Anyway we are talking about phase angles which are very very small, much below that what could become critical for a PA. 73, Stefan/DK7FC