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 x0PFbKQB030448 for ; Fri, 25 Jan 2019 16:37:21 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1gn3UJ-0006iS-F1 for rs_out_1@blacksheep.org; Fri, 25 Jan 2019 15:33:47 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1gn3UH-0006iD-Ej for rsgb_lf_group@blacksheep.org; Fri, 25 Jan 2019 15:33:45 +0000 Received: from smtp-out-6.talktalk.net ([62.24.135.70]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91) (envelope-from ) id 1gn3UF-0001Mc-Rg for rsgb_lf_group@blacksheep.org; Fri, 25 Jan 2019 15:33:44 +0000 Received: from malcoHP ([92.21.101.250]) by smtp.talktalk.net with SMTP id n3UEgFH7lpXFjn3UEgHmvN; Fri, 25 Jan 2019 15:33:42 +0000 X-DKIM-Result: Domain=talktalk.net Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=talktalk.net; s=cmr1711; t=1548430423; bh=SnmLozAbZowSv22goy8o7SwkYnD3SZuavQf5KFoQlK8=; h=From:To:References:In-Reply-To:Subject:Date; b=bHItRcFzDxAo18Mwi2R7dav3oEDWqGhussVFKT6ntzaToOMj5fS4e4x1WsFcsYt/Z DBOAzvMn26/vOzVm8pbGWljMnHFQKeuV4DF6oXAriAXCQ7AGdg25FNYxDU/u7r8d7e 2kGfPdLfTGHWWLb026+nSqpJWcOy+FHc0NXIoHqM= X-Originating-IP: [92.21.101.250] X-Spam: 0 X-OAuthority: v=2.3 cv=Ob228CbY c=1 sm=1 tr=0 a=y+NUerTrhrvXGTQNEzgoHA==:117 a=y+NUerTrhrvXGTQNEzgoHA==:17 a=IkcTkHD0fZMA:10 a=F3M5lZpKAAAA:8 a=hy2-l-Qa7Rc3Hx0fHkUA:9 a=QEXdDO2ut3YA:10 a=slCku8JSH3TyizEDQ3pD:22 Message-ID: <5E0CE31B798148D1A2D8CCDAC915736F@malcoHP> From: "mal hamilton" To: References: <1UTCTNxG9H.5T3bfQF3xD0@optiplex980-pc> <9C9C8088-AD45-4DDF-BD7E-66D13F0D835C@md.metrocast.net> <5C4B1BD5.6010404@posteo.de> In-Reply-To: <5C4B1BD5.6010404@posteo.de> Date: Fri, 25 Jan 2019 15:33:28 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 15.4.3508.1109 X-MimeOLE: Produced By Microsoft MimeOLE V15.4.3508.1109 X-CMAE-Envelope: MS4wfCZXma2pV20lmlCU77YXGx5vcroLAdqWUWpGPvlWEx6BnbfmeB55o4QYA+uiD9HBrqkhpE9+boY3JI2Y1pFvM82e1T1efA9CvXHCfP11O2//RA+RHPg1 qJnNGlTTWvIj2cPwI55yVbDIBH2wlXyZX/4GxKQWqAObUhbCcOEbK4RcjfkXdD6rIAac2YVBOPfsgA== 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. 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Content preview: DK7FC QRP- how is this possible ---is the world coming to an end!!!!!!!!!!!!!!! g3kev Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [62.24.135.70 listed in list.dnswl.org] -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: fc152e7304849b9a177649b85aea9f41 Subject: Re: LF: TXing WSPR/MF on an indoor loop Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=response 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=0.1 required=5.0 tests=MISSING_OUTLOOK_NAME 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 DK7FC QRP- how is this possible ---is the world coming to an end!!!!!!!!!!!!!!! g3kev -----Original Message----- From: DK7FC Sent: Friday, January 25, 2019 2:23 PM To: rsgb_lf_group@blacksheep.org Subject: LF: TXing WSPR/MF on an indoor loop Hi MF, A few days ago i took some RF litz wire and built a loop that is now hanging on the wall inside my home, just 1m besides the bed :-) (no XYL here spoiling the fun). The loop is beaming to about 150/330 deg. After playing some days on 160m (an unusual high frequency, witch feels very strange. And the band is full of unknown callsigns!!) i did now move down to more or less low frequencies, the 630m band! About 10 nF is needed to series resonate the loop. It has about 2m x 2m of size. The antenna current is not stable because the WIMA FKP-1 capacitor becomes warm during the 2 minute WSPR sequence. But the maximum current in the loop is 14 A. That explains why the cap becomes warm. A small parallel variable capacitor tunes to resonance. It is tuned so that the upheating capacitor runs into the resonance point in the middle of the WSPR sequence, then it runs out of the resonance by upheating further. It can cool down during the following quiet periods.. 14A into a 4 square meter loop at 475.7 kHz, how much ERP is that? The PA consumes about 3.5 A at 13.8V, i.e. about 50 W. The system will run over the weekend, even during daylight. The signal generator is a Raspi which will have no internet connectivity from now on, so let's hope the time offset stays inside the accepted range for this experiment. What will the best distance be? So far the band is closed but i'm optimistic to crack the 1000 km distance with this QRP setup. 73, Stefan