Return-Path: Received: from rly-mf06.mx.aol.com (rly-mf06.mail.aol.com [172.20.29.176]) by air-mf05.mail.aol.com (v125.7) with ESMTP id MAILINMF054-9644af54eab2f0; Sat, 07 Nov 2009 05:40:48 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mf06.mx.aol.com (v125.7) with ESMTP id MAILRELAYINMF062-9644af54eab2f0; Sat, 07 Nov 2009 05:40:45 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1N6ihY-00008Y-LQ for rs_out_1@blacksheep.org; Sat, 07 Nov 2009 10:39:24 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1N6ihY-00008P-2d for rsgb_lf_group@blacksheep.org; Sat, 07 Nov 2009 10:39:24 +0000 Received: from mail.gmx.net ([213.165.64.20]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1N6igT-0003rp-Mm for rsgb_lf_group@blacksheep.org; Sat, 07 Nov 2009 10:38:18 +0000 Received: (qmail invoked by alias); 07 Nov 2009 10:39:16 -0000 Received: from p5DC43A36.dip.t-dialin.net (EHLO Clemens04) [93.196.58.54] by mail.gmx.net (mp061) with SMTP; 07 Nov 2009 11:39:16 +0100 X-Authenticated: #17214767 X-Provags-ID: V01U2FsdGVkX1/+/oIUQzn+CtomO/icN5kn6h36p6p7FpyQtAUaj1 vGFLTEzdNXjZQN Message-ID: <005801ca5f96$8ddffbc0$0201a8c0@Clemens04> From: "Clemens Paul" To: References: <1686106A1FF945FDB9AC52BD1ECAFB77@df2py> Date: Sat, 7 Nov 2009 11:39:08 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3598 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3350 X-Y-GMX-Trusted: 0 X-FuHaFi: 0.51,0.52 X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: Re: Stainless steel versus copper Content-Type: multipart/alternative; boundary="----=_NextPart_000_0054_01CA5F9E.EB1B0B10" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,HTML_MESSAGE 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 X-AOL-IP: 193.82.116.20 ------=_NextPart_000_0054_01CA5F9E.EB1B0B10 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Hello Wolf, Regarding steel wire losses depend highly on the kind of steel and on the kind of antenna (resonant or not). Magnetic steel should be avoided because its µrel is unknown and changes over frequency. On shortwave I've measured a factor of ~13 steel vs copper for *rf* losses of a 2mm steel antenna litz wire, manufactured by a former German antenna producer (Fritzel). This closely matches with numbers found in Gerd Janzen's book "Kurze Antennen". Therefore the efficiency for a half wave dipole is about 89% (0,5dB) and 84% (0,76dB) for a fullwave loop made of this type of steel. Losses of steel antenna wire really become detrimental if you use short antennas because of the low radiation resistance. So for MW/LW,where most of us have extremely short antenas in terms of wavelength steel wire is not advisable for antennas. Losses of feeders made of steel,with reasonable diameter (say 2mm) are in the same range as with resonant dipoles or resonant loops,i.e. neglectable for our purposes. 73 Clemens DL4RAJ ----- Original Message ----- From: Wolf Ostwald To: rsgb_lf_group@blacksheep.org Sent: Saturday, November 07, 2009 8:23 AM Subject: LF: Stainless steel versus copper Hi ! Is there any experience around about using stainless steel wires for toploads or feeders versus copper ? As to my knowledge there is a certain amount of rf current penetrating into the conductor at 137/500 kHz. Losses are expected to be high in lesser conductive materials at those frequencies. Any ideas about the order of magnitude in current fed antennas ? 73 de wolf df2py / di2bj ------------------------------------------------------------------------------ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.425 / Virus Database: 270.14.52/2484 - Release Date: 11/06/09 07:38:00 ------=_NextPart_000_0054_01CA5F9E.EB1B0B10 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hello Wolf,
 
Regarding steel wire losses depend highly on the kind of ste= el
and=20 on the kind of antenna (resonant or not).
Magnetic steel should be= avoided=20 because its =B5rel is unknown and=20
changes over frequency. 

On shortwave I've measured= a factor of=20 ~13 steel vs copper for *rf*  losses of a 2mm
steel anten= na litz=20 wire, manufactured by a former German antenna producer (Fritzel).=
This closely matches with numbers found in Gerd Janzen's book "Ku= rze=20 Antennen".
Therefore the efficiency for a half wave dipole is about= 89%=20 (0,5dB)
and 84% (0,76dB) for a fullwave loop made of this= type of=20 steel.
Losses of steel antenna wire really become detrimental if yo= u use=20 short antennas because of
the low radiation resistance.
So for MW/LW,where most of us have extremely short antenas in ter= ms of=20 wavelength
steel wire is not advisable for antennas.
Losses of feeders made of steel,with= reasonable=20 diameter (say 2mm) are in the same range
as with resonant dipoles or resonant= loops,i.e. neglectable for our= =20 purposes.

73
Clemens
DL4RAJ
----- Original Message -----
From:=20 Wolf= Ostwald=20
Sent: Saturday, November 07,= 2009 8:23=20 AM
Subject: LF: Stainless steel= versus=20 copper

Hi !

Is there any experi= ence around=20 about using stainless steel wires for toploads or feeders versus cop= per=20 ?

As to my knowledge= there is a=20 certain amount of rf current penetrating into the conductor at 137/5= 00 kHz.=20 Losses are expected to be high in lesser conductive materials at tho= se=20 frequencies. Any ideas about the order of magnitude in current fed= antennas=20 ?

73 de wolf  df= 2py /=20 di2bj


No virus found in this incoming message.
Checked by AV= G -=20 www.avg.com
Version: 8.5.425 / Virus Database: 270.14.52/2484 -= Release=20 Date: 11/06/09 07:38:00
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