Return-Path: X-Spam-DCC: paranoid 1233; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, NO_REAL_NAME autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id tBKN1C4I020967 for ; Mon, 21 Dec 2015 00:01:12 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1aAmvS-0001tz-1X for rs_out_1@blacksheep.org; Sun, 20 Dec 2015 22:58:02 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1aAmvQ-0001tb-Vp for rsgb_lf_group@blacksheep.org; Sun, 20 Dec 2015 22:58:00 +0000 Received: from resqmta-po-07v.sys.comcast.net ([96.114.154.166]) by relay1.thorcom.net with esmtps (TLSv1.2:DHE-RSA-AES256-SHA:256) (Exim 4.86) (envelope-from ) id 1aAmuN-0007M7-2U for rsgb_lf_group@blacksheep.org; Sun, 20 Dec 2015 22:57:59 +0000 Received: from resomta-po-06v.sys.comcast.net ([96.114.154.230]) by resqmta-po-07v.sys.comcast.net with comcast id vywc1r00A4yXVJQ01ywc05; Sun, 20 Dec 2015 22:56:36 +0000 Received: from Owner ([69.143.126.100]) by resomta-po-06v.sys.comcast.net with comcast id vywb1r0082A5djZ01ywcAg; Sun, 20 Dec 2015 22:56:36 +0000 X-DKIM-Result: Domain=comcast.net Result=Signature OK From: To: References: <8D30934359654D8-15C4-3DDFF4@webmail-vm170.sysops.aol.com> <0EF07ED4EE1B45BDBB86B44B855B03BF@gnat> <68629D3DB5E840F098999D75247C9777@gnat> <5677202D.8070200@abelian.org> In-Reply-To: <5677202D.8070200@abelian.org> Date: Sun, 20 Dec 2015 17:56:24 -0500 Message-ID: <00a201d13b79$ac0c1690$042443b0$@comcast.net> MIME-Version: 1.0 X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQI26bI11d3U9JBi1f/cWCNDA/ToRwHgIWjSAZrg9k8Agmd6KgDo6MMmAh4ibwoBe0CchJ3FHu+w Content-Language: en-us DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=q20140121; t=1450652196; bh=XIisY6eIhHjSKvt+GYZww8ZXzE6heyCW7o1NTOEoHcc=; h=Received:Received:From:To:Subject:Date:Message-ID:MIME-Version: Content-Type; b=I1LNrw0FZXIgnmq48CoRehkMiDWAF1IFcgLP3kQY7VeOEZRcyk16LAXJf2ey96eC/ F0y+wpLdsdAxQCM0YQYPa+C6f9XmfjuI8Jp+jbyWRcktRwoCyXFRA/oWJohWYX0/qf ibq4px1hlZJ1up12ofmkXjgPQcOp3O4zp0s2PjA3OToBosX3ZSkVVKcBO64gd3tUQy 71+xQFo18vWHT+jgAdE+BkBPxn//jKNO6XHyZStJU47WnrwuFgxhcduTybqt8+emKq sv/RI0iWRb5tDoxgj23nc7+A0ebV+fH9oR2OWT4yHqvbx3lIkWtLhIKd5sV9xCVQkz 0eRKK4c6oTTDQ== X-Scan-Signature: fc152e7304849b9a177649b85aea9f41 Subject: RE: LF: VLF in VO Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit 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-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 5865 Paul, Ref: " I can easily see 10uW from 1000km in one hour over a path with a lot of land. West to east over water will be lower loss and four or six hours integration will make up for the lower ERP." Would you tend to allocate another 10db-15dB or so of loss for waveguide coupling efficiency given horizontal polarization and low-order mode? (long paths favor low-order modes, and low-order modes couple inefficiently to the waveguide when polarization is horizontal). NEC seems to think that the waveguide coupling penalty for (electrically small VLF) horizontal antennas is about 15dB but I don't put much trust in NEC solutions for electrically small VLF antennas. Jim AA5BW -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Paul Nicholson Sent: Sunday, December 20, 2015 4:40 PM To: rsgb_lf_group@blacksheep.org Subject: Re: LF: VLF in VO > About 30 watts were fed to a 5:1 XFMR and a ~0.35H > tuning coil to the 100m wire at 10m height. > The ERP was about 3uW. How about a long carrier, GPS or rubidium? It's a long shot but it's a low loss path and the time of year is good for several hours of coherent integration. I can easily see 10uW from 1000km in one hour over a path with a lot of land. West to east over water will be lower loss and four or six hours integration will make up for the lower ERP. -- Paul Nicholson --