Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mj06.r1000.mx.aol.com (Internet Inbound) with ESMTP id B76FF380000A7; Sat, 15 Dec 2012 16:51:51 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1TjzcV-0004Kw-Hh for rs_out_1@blacksheep.org; Sat, 15 Dec 2012 21:50:07 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1TjzcU-0004Kn-T0 for rsgb_lf_group@blacksheep.org; Sat, 15 Dec 2012 21:50:06 +0000 Received: from mail-la0-f43.google.com ([209.85.215.43]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1TjzcS-0006I7-Uv for rsgb_lf_group@blacksheep.org; Sat, 15 Dec 2012 21:50:05 +0000 Received: by mail-la0-f43.google.com with SMTP id z14so3700481lag.16 for ; Sat, 15 Dec 2012 13:49:43 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=Tkjx2FCv6ZdtZkrgGx7NB35bxIx03wmlCaUIgZUHclI=; b=yLV+mamTK9n/jcjeRF266C9fHELdST+Y989IATaFpmXFC4VsKbm8QN285YlLIYHhmv I5ip0OjfUq2+ibK+lNcVwEouEP3co1nnQ5Zqz0mKdw/Qw7fT3lkmZ+6E/E6WVcHf6wsh fQFRo4qjzeUht86uPYj2WqFUYpl/4UZ1Oo0BWShsRG+KGkyHTg+hJumBBbe99Avhe0Rn JoER313jafsJW9WgtORsVKWB5OcRswbRbiVHbnS7E9Eln727gnMkM15cCFYn2/1Zyza8 4J92fuw3PttJ8/SniiSKHOpZDwSx3yL4Zt5Dl1IDqsh5xjKHSBcBCxVDJoWdk4I4zgVH S2Rg== MIME-Version: 1.0 Received: by 10.152.111.68 with SMTP id ig4mr6680240lab.50.1355608183524; Sat, 15 Dec 2012 13:49:43 -0800 (PST) Received: by 10.114.21.4 with HTTP; Sat, 15 Dec 2012 13:49:43 -0800 (PST) In-Reply-To: References: Date: Sat, 15 Dec 2012 16:49:43 -0500 Message-ID: From: Warren Ziegler To: rsgb_lf_group X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Thank you Jim, Stefan, Mal Good information! I will be putting it into practice soon! 73 Warren On Sat, Dec 15, 2012 at 3:55 PM, James Moritz wrote: > Dear Warren, LF Group, > > It's a long time ago now, but... > The multi-stranded winding was mainly used because it is much more flexible > and so easier to wind onto the core. I used a salvaged LOPT core as if it > were a toroid core, i.e. fixing the two core halves together before > threading the wire through the aperture repeatedly to produce the winding. > Producing a compact, even winding that lay snugly on the core using solid > wire was difficult because of the stiffness of the wire. It is desireable > to > make the windings as compact as possible with the minimum amount of space > between the turns in order to reduce the leakage inductance of the > transformer as much as possible. This raises the self-resonant frequency of > the transformer and reduces the amount of RC damping needed to produce a > sensible drain waveform. The multiple strands do probably give some > reduction in losses at 137k, but I expect only marginally. > > Cheers, Jim Moritz > 73 de M0BMU > > > [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.215.43 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (wd2xgj[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 4f449c45f7b1894a9195a328eedaeb30 Subject: Re: LF: Re: M0BMU mods to the G0MRF PA Content-Type: multipart/alternative; boundary=f46d04083b513bcdd404d0eb2011 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=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-global-disposition: G X-AOL-SCOLL-AUTHENTICATION: mtain-mj06.r1000.mx.aol.com ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d7b9a50ccf0f759d2 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --f46d04083b513bcdd404d0eb2011 Content-Type: text/plain; charset=ISO-8859-1 Thank you Jim, Stefan, Mal Good information! I will be putting it into practice soon! 73 Warren On Sat, Dec 15, 2012 at 3:55 PM, James Moritz wrote: > Dear Warren, LF Group, > > It's a long time ago now, but... > The multi-stranded winding was mainly used because it is much more flexible > and so easier to wind onto the core. I used a salvaged LOPT core as if it > were a toroid core, i.e. fixing the two core halves together before > threading the wire through the aperture repeatedly to produce the winding. > Producing a compact, even winding that lay snugly on the core using solid > wire was difficult because of the stiffness of the wire. It is desireable > to > make the windings as compact as possible with the minimum amount of space > between the turns in order to reduce the leakage inductance of the > transformer as much as possible. This raises the self-resonant frequency of > the transformer and reduces the amount of RC damping needed to produce a > sensible drain waveform. The multiple strands do probably give some > reduction in losses at 137k, but I expect only marginally. > > Cheers, Jim Moritz > 73 de M0BMU > > > -- 73 Warren K2ORS WD2XGJ WD2XSH/23 WE2XEB/2 WE2XGR/1 --f46d04083b513bcdd404d0eb2011 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Thank you Jim, Stefan, Mal=A0
Good information!=A0
I will be = putting it into practice soon!
73 Warren



On Sat, Dec 15, 2= 012 at 3:55 PM, James Moritz <james.moritz@btopenworld.com&= gt; wrote:
Dear Warren, LF Group,

It's a long time ago now, but...
The multi-stranded winding was mainly used because it is much more flexible=
and so easier to wind onto the core. I used a salvaged LOPT core as if it were a toroid core, i.e. fixing the two core halves together before
threading the wire through the aperture repeatedly to produce the winding.<= br> Producing a compact, even winding that lay snugly on the core using solid wire was difficult because of the stiffness of the wire. It is desireable t= o
make the windings as compact as possible with the minimum amount of space between the turns in order to reduce the leakage inductance of the
transformer as much as possible. This raises the self-resonant frequency of=
the transformer and reduces the amount of RC damping needed to produce a sensible drain waveform. The multiple strands do probably give some
reduction in losses at 137k, but I expect only marginally.

Cheers, Jim Moritz
73 de M0BMU





--
73 Warren K2= ORS
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 WD2XGJ
=A0 =A0 =A0 =A0 =A0 =A0 = =A0 =A0 WD2XSH/23
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 WE2XEB/2
=A0 =A0 = =A0 =A0 =A0 =A0 =A0 =A0 WE2XGR/1

=A0
--f46d04083b513bcdd404d0eb2011--