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 w159e3AS014155 for ; Mon, 5 Feb 2018 10:40:04 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eidBi-0005cc-8G for rs_out_1@blacksheep.org; Mon, 05 Feb 2018 09:35:46 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eidBh-0005cT-VZ for rsgb_lf_group@blacksheep.org; Mon, 05 Feb 2018 09:35:45 +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 1eidBf-0006yG-7w for rsgb_lf_group@blacksheep.org; Mon, 05 Feb 2018 09:35:44 +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:From:References:To:Subject:Sender:Reply-To: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=VFf0LPJBGxq5PZ5NwYbTGcrnl+oH+W8nFQaX2RpH4aM=; b=5Bo0lxKqPO+S0kYPwNHHI3nPAV Od6M9NyaO9fZS3OSaHBkZigC4iS8qtSXekDlvTjKWfMAmxQGkZ1jHaWhBGgJVtyP0bcEZeHFOGWYu 5mxZ3NLpwXI5okqayrojlS3Vw0CUusqIbGAkVLzDQA6ULP9HAR/GDNC63dA9JNRJpYGc=; Received: from i-194-106-52-83.freedom2surf.net ([194.106.52.83]:57320 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 1eidBd-0004GZ-FV for rsgb_lf_group@blacksheep.org; Mon, 05 Feb 2018 09:35:41 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by pn.abelian.org (Postfix) with ESMTP id E474D4000D5 for ; Mon, 5 Feb 2018 09:35:40 +0000 (UTC) To: rsgb_lf_group@blacksheep.org References: <579355A36AEE9D4FA555C45D556003AB9AB49FE8@servigilant.vigilant.local> From: Paul Nicholson Message-ID: Date: Mon, 5 Feb 2018 09:35:40 +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: <579355A36AEE9D4FA555C45D556003AB9AB49FE8@servigilant.vigilant.local> 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: Thank you Tom, that was a most interesting post with much food for thought. Nice construction and good to see an alternative to air-cored loading coils. The increase of inductance with current is curious. An artifact of the test setup? Interesting point about the audio channels being out of phase. [...] 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: 4e3b1488273adbbe9757d6bdd5adf219 Subject: Re: New station on VLF: DK1IS Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit 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 Thank you Tom, that was a most interesting post with much food for thought. Nice construction and good to see an alternative to air-cored loading coils. The increase of inductance with current is curious. An artifact of the test setup? Interesting point about the audio channels being out of phase. Do you have any feedback from an E-field probe to stabilise the phase? Perhaps that's not necessary with the relatively low Q system. The antenna wires spaced one 1 metre - I assume 1 metre between each wire. The 160 ohms antenna resistance, that must be mostly ground resistance? > It´s always a little bit frustrating that I can´t hear my own > signal even at the VLF RX site at our club station DL0AO only > 6 km away in a forest. Sometimes they become audible when a long transmission is played back time compressed. I tried that with your 28th carrier but even with x20000 compression it was still not audible. The ferrite chokes look a lot like RS components 715-6857, which happen to be the same ones I use for filtering in my 48V rx power supply. 10mH, Rdc = 3.394 Ohms. -- Paul Nicholson --