Return-Path: X-Spam-DCC: paranoid 1290; 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=-0.7 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE,RATWARE_GECKO_BUILD,SPF_PASS 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 u97NYwTc006231 for ; Sat, 8 Oct 2016 01:34:58 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1bsebe-0008Pq-89 for rs_out_1@blacksheep.org; Sat, 08 Oct 2016 00:31:10 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1bsebd-0008Ph-Jm for rsgb_lf_group@blacksheep.org; Sat, 08 Oct 2016 00:31:09 +0100 Received: from mout02.posteo.de ([185.67.36.66]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1bsebO-00022v-OB for rsgb_lf_group@blacksheep.org; Sat, 08 Oct 2016 00:31:08 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id 5298420827 for ; Sat, 8 Oct 2016 01:30:51 +0200 (CEST) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3srQkL6thYzytl for ; Sat, 8 Oct 2016 01:30:50 +0200 (CEST) Message-ID: <57F83029.8010104@posteo.de> Date: Sat, 08 Oct 2016 01:30:49 +0200 From: DK7FC 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: <154c32c4dba-373a-24653@webprd-m58.mail.aol.com> <573CAF79.9040701@abelian.org> <573CBBF0.4030701@posteo.de> <573E5907.6020107@posteo.de> <573EA094.3040205@abelian.org> <573EF90F.1080201@posteo.de> <573FC4DA.3080107@abelian.org> <5740842D.3030000@posteo.de> <5744FA27.6010703@posteo.de> <57F56531.3060205@posteo.de> <57F78A3F.5030803@posteo.de> <57F80D22.2020800@posteo.de> In-Reply-To: <57F80D22.2020800@posteo.de> X-Scan-Signature: 7f2e5481aa97b3cbff3d653a1b2ddfbd Subject: ULF: A new step on the large ULF coil... Content-Type: multipart/alternative; boundary="------------070701020706030208030607" 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 10.1.3.11 Status: RO X-Status: X-Keywords: X-UID: 8963 This is a multi-part message in MIME format. --------------070701020706030208030607 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi ULF, This night i have completed the 4th stack of my large *ULF loading coil*. An image: *https://dl.dropboxusercontent.com/u/19882028/ULF/20161008_ULF_TX_coil.jpg* The exciting question was, what is the new resonance frequency together with my antenna. In the lab i put an equivalent C in parallel and found the resonance peak at *3.67 kHz*. So the L seems to be *3.8 H* now. This is still not enough. The l/d of the coil dimension becomes larger now, so i need more and more wire to reach the final resonance frequency of 2.97 kHz at about 500 pF. I will do a next test on the actual resonance frequency in some days, when the WX permits. I will also check where the resonance can be found when switching the small coil in series that i use for 6.47 kHz now. It could be quite close to 2.97 kHz then! So maybe this allows a next QRO step on 2.97 kHz: 100 mA antenna current must be reached for the planned experiment in 65 km distance. BTW the 4 stack coil is wound out of almost 4 kg of enameled Cu wire with 0.4 mm diameter. The layers are isolated by Kapton tape. My assumption is that it will hold 20 kV now. Ah and the *DC resistance is 445 Ohm* now. When connecting 275 V AC / 50 Hz, i can measure 269 mA. So the actual inductance is *2.93 H* (beeing farer away from the self resonance frequency) I can tell you it's quite fascinating to operate down on these low frequencies :-) To be continued... 73, Stefan/DK7FC --------------070701020706030208030607 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi ULF,

This night i have completed the 4th stack of my large ULF loading coil.
An image: https://dl.dropboxusercontent.com/u/19882028/ULF/20161008_ULF_TX_coil.jpg

The exciting question was, what is the new resonance frequency together with my antenna. In the lab i put an equivalent C in parallel and found the resonance peak at 3.67 kHz. So the L seems to be 3.8 H now. This is still not enough. The l/d of the coil dimension becomes larger now, so i need more and more wire to reach the final resonance frequency of 2.97 kHz at about 500 pF.

I will do a next test on the actual resonance frequency in some days, when the WX permits. I will also check where the resonance can be found when switching the small coil in series that i use for 6.47 kHz now. It could be quite close to 2.97 kHz then! So maybe this allows a next QRO step on 2.97 kHz: 100 mA antenna current must be reached for the planned experiment in 65 km distance.

BTW the 4 stack coil is wound out of almost 4 kg of enameled Cu wire with 0.4 mm diameter. The layers are isolated by Kapton tape. My assumption is that it will hold 20 kV now.
Ah and the DC resistance is 445 Ohm now. When connecting 275 V AC / 50 Hz, i can measure 269 mA. So the actual inductance is 2.93 H (beeing farer away from the self resonance frequency)

I can tell you it's quite fascinating to operate down on these low frequencies :-) To be continued...

73, Stefan/DK7FC
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