Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id vBQGJlLZ029181 for ; Tue, 26 Dec 2017 17:19:49 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eTrsX-0003lM-SL for rs_out_1@blacksheep.org; Tue, 26 Dec 2017 16:14:57 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eTrsX-0003lD-FD for rsgb_lf_group@blacksheep.org; Tue, 26 Dec 2017 16:14:57 +0000 Received: from porthos.netcom.co.uk ([217.72.171.73]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1eTrsU-0005gK-NE for rsgb_lf_group@blacksheep.org; Tue, 26 Dec 2017 16:14:56 +0000 X-DKIM-Result: Domain=abelian.org Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:References:Reply-To:To:From:Subject:Sender:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=hrIwl/CwP0HSfiZKwNWSx1qMTJJOl+UTCNFYlgbMwIw=; b=NDMEBgLbnLrPVr/W/N11n8SY+/ dSLShIaEJ959COP+joUULZRKZpS5qiv2IN7n9/nIIKzpav7Au2EqgbFNFb8nCdVi7hkevzLulYGPu KuqBm7YkO1pnaUsi0keazPaIHZrkY/6YCtzt9OaCX72vv5z6P7z3c3LCEXTARZ59GakA=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:46890 helo=pn.abelian.org) by porthos.netcom.co.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1eTrsT-0007nB-VX for rsgb_lf_group@blacksheep.org; Tue, 26 Dec 2017 16:14:54 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id 63F8F4000C1 for ; Tue, 26 Dec 2017 16:14:53 +0000 (UTC) From: Paul Nicholson To: rsgb_lf_group@blacksheep.org References: <4d96a9d4-5f22-7650-872b-6344e9aea8e3@abelian.org> <27BE047B-55C1-45E1-9BD8-575D5EF7179C@hurontel.on.ca> <4c4d7934-b02f-0c9f-e251-4c5a07086bef@abelian.org> <526a4012-19d5-aff0-0745-4b02a3a134e8@abelian.org> <5A2FD635.8080503@posteo.de> <807b7164-c345-9650-0c6b-d813b3304483@abelian.org> <0374401c-a9a5-ba61-89e0-15d5ad016ac8@abelian.org> <36a938b7-9db4-7417-26d6-5b4c4eac900e@abelian.org> <5A35A023.5010707@posteo.de> <1f5204c1-f256-f26e-e6dd-a4edc0c8a443@abelian.org> <579355A36AEE9D4FA555C45D556003AB9AABBD7A@servigilant.vigilant.local> <5086126d-5770-653c-6cf0-fd8b1a4a860c@abelian.org> <3428fb07-6b88-4b82-8e8d-ea7d9ea07a47@abelian.org> <5A3E7C5E.7080506@posteo.de> <44f8501d-9d57-2793-b33e-ee4a2e80d6a4@abelian.org> Message-ID: Date: Tue, 26 Dec 2017 16:14:53 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <44f8501d-9d57-2793-b33e-ee4a2e80d6a4@abelian.org> Content-Language: en-US X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - porthos.netcom.co.uk X-AntiAbuse: Original Domain - blacksheep.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - abelian.org X-Get-Message-Sender-Via: porthos.netcom.co.uk: authenticated_id: catchall@abelian.org X-Authenticated-Sender: porthos.netcom.co.uk: catchall@abelian.org X-Spam-Score: 0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Varying the E/H mix on recent carriers and EbNaut signals fails to improve S/N when I move away from the calibrated mix. That's a good sign but it's not quite right yet. Measured E/H is tending to come out a little on the high side of 376 ohms, where it should really be equal to or lower than the free-space value. Lower with more local signals which would have higher elevation of incident signal. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 1708620d3ce65bee0beaaede7929769a Subject: Re: LF: RE: Todmorden receiver Content-Type: text/plain; charset=utf-8; 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=0.9 required=5.0 tests=FROM_ENDS_IN_NUMS 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 Varying the E/H mix on recent carriers and EbNaut signals fails to improve S/N when I move away from the calibrated mix. That's a good sign but it's not quite right yet. Measured E/H is tending to come out a little on the high side of 376 ohms, where it should really be equal to or lower than the free-space value. Lower with more local signals which would have higher elevation of incident signal. Today I measured the loop area more carefully. The ground beneath is uneven so I had to integrate - just W*H is no longer accurate enough. The nice thing about loops is that they are easy to calibrate accurately, compared with E-field probes which need careful modeling of charge distribution to determine the effective height. The E-field model isn't quite right at the moment since I repositioned the clamps. I think the effective height is higher now than modeled. Perhaps enough to fix the error? If the calibration can be refined sufficiently well, it ought to be possible to adjust the antenna synthesis not just for azimuth, but for elevation and polarisation too, to achieve a further small increase in S/N. fbins spectrogram is currently running with the old calibration and therefore won't have a good front/back ratio or optimum sensitivity. When I've pinned down the calibration a bit tighter, I can recalculate the spectrogram data, backdating to midday 20th when the new H rx was activated. > better keep some of the sausages ;-) Nobody had a camera the other day to capture the bizarre sight of someone running along a muddy farm track carrying a car battery and a spectrum analyser with an angry dog snapping at his wellies. I had no spare hand to throw sausages. -- Paul Nicholson --