Return-Path: X-Spam-DCC: paranoid 1290; Body=3 Fuz1=3 Fuz2=3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, FORGED_RCVD_HELO,HTML_50_60,HTML_IMAGE_ONLY_32,HTML_MESSAGE 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 t41CDNe4014929 for ; Fri, 1 May 2015 14:13:23 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Yo9kt-0003kD-MP for rs_out_1@blacksheep.org; Fri, 01 May 2015 13:09:19 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Yo9kt-0003k4-6r for rsgb_lf_group@blacksheep.org; Fri, 01 May 2015 13:09:19 +0100 Received: from rhcavuit02.kulnet.kuleuven.be ([134.58.240.130] helo=cavuit02.kulnet.kuleuven.be) by relay1.thorcom.net with esmtp (Exim 4.85) (envelope-from ) id 1Yo9kr-0001lN-4w for rsgb_lf_group@blacksheep.org; Fri, 01 May 2015 13:09:18 +0100 X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-KULeuven-Scanned: Found to be clean X-KULeuven-ID: B9C10128342.A0EC9 X-KULeuven-Information: Katholieke Universiteit Leuven Received: from icts-p-smtps-1.cc.kuleuven.be (icts-p-smtps-1e.kulnet.kuleuven.be [134.58.240.33]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id B9C10128342 for ; Fri, 1 May 2015 14:09:13 +0200 (CEST) Received: from ICTS-S-HUB4.luna.kuleuven.be (icts-s-hub4.luna.kuleuven.be [10.112.9.18]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by icts-p-smtps-1.cc.kuleuven.be (Postfix) with ESMTPS id B363340A8 for ; Fri, 1 May 2015 14:09:13 +0200 (CEST) Received: from ICTS-S-MBX1.luna.kuleuven.be ([fe80::edaf:341f:90e:f70e]) by ICTS-S-HUB4.luna.kuleuven.be ([fe80::c11b:83f0:c46c:c366%26]) with mapi id 14.03.0224.002; Fri, 1 May 2015 14:09:13 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Thread-Topic: questions about a tx square loop fpr 470KHz Thread-Index: AQHQg4vYEtT05yzLr0y3IMBd/C1uIZ1nBNmW Date: Fri, 1 May 2015 12:09:12 +0000 Message-ID: <7E7DFBB4D102A04DB5ADC88D66628A4A23538F51@ICTS-S-MBX1.luna.kuleuven.be> References: <579355A36AEE9D4FA555C45D556003AB1B0F416E@servigilant.vigilant.local> <553FFAC1.7060609@gmail.com>, In-Reply-To: Accept-Language: nl-BE, en-GB, en-US Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.112.13.14] MIME-Version: 1.0 X-HELO-Warning: Remote host 134.58.240.130 (rhcavuit02.kulnet.kuleuven.be) used invalid HELO/EHLO cavuit02.kulnet.kuleuven.be - verification failed X-Scan-Signature: b2000330e4064ca60a9f57e731b892da Subject: LF: RE: questions about a tx square loop fpr 470KHz Content-Type: multipart/alternative; boundary="_000_7E7DFBB4D102A04DB5ADC88D66628A4A23538F51ICTSSMBX1lunaku_" 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: 3034 --_000_7E7DFBB4D102A04DB5ADC88D66628A4A23538F51ICTSSMBX1lunaku_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Mauro, with this dimensions the antenna impedance will be mainly determined by the= loss resistance. For a loop circumference of 20m and a 2 turn loop the copper resistance wil= l be about 0.13 Ohm. Putting 20 W into 0.13 Ohm will cause a current of 12.5A, no problem for a = 6mm^2 wire. But the location of the loop seems far from perfect, very close to a wall a= nd even some metal objects inside the loop perimeter. This will increase th= e loss resistance significantly beyond the 0.13 Ohm copper loss. 73, Rik ON7YD - OR7T ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org= ] namens IK1WVQ Mauro [ik1wvq@stmb.it] Verzonden: donderdag 30 april 2015 23:16 Aan: rsgb_lf_group@blacksheep.org; rsgb_lf_group@blacksheep.org Onderwerp: LF: questions about a tx square loop fpr 470KHz 73 to all, I would like to know your opinion about this: I can made a square TX loop for 470KHz of 7 * 3 meters (see picture) in the= terrace of the building where I live (6 floors). the questions are: - it is enough a 6mmq copper electric wire ?? (20W is the output power of = my tx). - single turn or two turns spaced 10cm max ?? (two turns =3D less pF requi= red to take the resonance). - Is this a good idea to start to trasmit on 470KHz WSPR ?? thanks in advance for your attention. 73 de Mauro IK1WVQ ________________________________ [Avast logo] Questa e-mail =E8 stata controllata per individuare virus con Avast antivir= us. www.avast.com --_000_7E7DFBB4D102A04DB5ADC88D66628A4A23538F51ICTSSMBX1lunaku_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Hi Mauro,

 

with this dimensions the antenna impedance will be mainly determined by = the loss resistance.

For a loop circumference of 20m and a 2 turn loop the copper resistance = will be about 0.13 Ohm.

Putting 20 W into 0.13 Ohm will cause a current of 12.5A, no problem for= a 6mm^2 wire.

But the location of the loop seems far from perfect, very close to a wal= l and even some metal objects inside the loop perimeter. This will increase= the loss resistance significantly beyond the 0.13 Ohm copper loss.

 

73, Rik  ON7YD - OR7T

 

Van: owner-rsgb_lf_group@blacksheep.org [o= wner-rsgb_lf_group@blacksheep.org] namens IK1WVQ Mauro [ik1wvq@stmb.it]
Verzonden: donderdag 30 april 2015 23:16
Aan: rsgb_lf_group@blacksheep.org; rsgb_lf_group@blacksheep.org
Onderwerp: LF: questions about a tx square loop fpr 470KHz


73 to all,

I would like to know your opinion about this:

I can made a square TX loop for 470KHz of 7 * 3 meters (see picture) in the= terrace of the building where I live (6 floors).

the questions are:

- it is enough a 6mmq copper electric wire ??  (20W is the output powe= r of my tx).
- single turn or two turns spaced 10cm max ?? (two turns =3D  less pF = required to take the resonance).
- Is this a good idea to start to trasmit on 470KHz WSPR ??

thanks in advance for your attention.

73 de Mauro IK1WVQ



=3D"Avast

Questa e-mail =E8 stata controllata per individuare virus con Avast antivir= us.
www.avast.com


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