Return-Path: Received: from mtain-mh02.r1000.mx.aol.com (mtain-mh02.r1000.mx.aol.com [172.29.96.214]) by air-mc08.mail.aol.com (v129.4) with ESMTP id MAILINMC084-a98e4d6235fd1ee; Mon, 21 Feb 2011 04:53:01 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mh02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1A2BB380000B9; Mon, 21 Feb 2011 04:52:59 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PrSQi-0003Xa-LS for rs_out_1@blacksheep.org; Mon, 21 Feb 2011 09:51:44 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PrSQh-0003XR-5j for rsgb_lf_group@blacksheep.org; Mon, 21 Feb 2011 09:51:43 +0000 Received: from out1.ip01ir2.opaltelecom.net ([62.24.128.237]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PrSQf-0006jx-9l for rsgb_lf_group@blacksheep.org; Mon, 21 Feb 2011 09:51:43 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AjEBAMvEYU1Ok82y/2dsb2JhbACCSYFWj04Dg3KOSnOpF49/hGh2BIFojgA X-IronPort-AV: E=Sophos;i="4.62,199,1297036800"; d="scan'208,217";a="344191580" Received: from unknown (HELO xphd97xgq27nyf) ([78.147.205.178]) by out1.ip01ir2.opaltelecom.net with SMTP; 21 Feb 2011 09:51:34 +0000 Message-ID: <001301cbd1ac$ead615b0$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <004201cbd111$5d4567f0$0401a8c0@xphd97xgq27nyf> <949432225.7185542.1298229766613.JavaMail.fmail@mwmweb068> Date: Mon, 21 Feb 2011 09:51:30 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126 Subject: Re: LF: toroid xformer Content-Type: multipart/alternative; boundary="----=_NextPart_000_0010_01CBD1AC.EA746DB0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_40_50,HTML_MESSAGE, HTML_TAG_EXISTS_TBODY 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-sid: 3039ac1d60d64d6235fb4455 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_0010_01CBD1AC.EA746DB0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hans Thanks for the info. I have several toroid wound mains transformers and wondered if they wo= uld be any use. A couple of persons have mentioned using this type on= VLF.=20 I have a number of old LOPT cores and these would be more suitable. I= use these on 137 and 500 and they work well. 73 de mal/g3kev ----- Original Message -----=20 From: Hans-Albrecht Haffa=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Sunday, February 20, 2011 7:22 PM Subject: Re: LF: toroid xformer Dear Mal, do not expect anything from laminated sheet iron cores. Usable frequ= encxys depends on the thicknes of the Iron sheets, and the conductivit= y ot the material. Therefore the iron is alloyed with silicon and alum= inium, to reduce edding currents. Best frequ. for Mains transformers= is 200 Hz, with superior sheet iron 400 Hz. Toroid cores from vitrous= glasses would be best, but are not available, only as catalog numbers= at Vacuumschmelze Hanau or Arnold, Micrometals and other manufacturer= s of materials. They do not offer kits with cores and coilformers . Th= is problem is widely discussed in students lessons of the type "Maxwel= ls equations and the transformer with laminated Iron core. " 55, Hans-Albrecht DK 8 ND ----------------------------------------------------------------------= ------ Von: "mal hamilton" Gesendet: 20.02.2011 16:18:01 An: rsgb Betreff: LF: toroid xformer LF Has anyone measured the efficiency of a mains toroid xformer on 9= Khz. I have some of these which could be useful. ie 230v Prim and 6/12/24 v Sec, rated 10A at 12v de mal/g3kev =20 =20 NEU: FreePhone - kostenlos mobil telefonieren und surfen! = =20 Jetzt informieren: http://produkte.web.de/go/webdefreephone=20 ------=_NextPart_000_0010_01CBD1AC.EA746DB0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hans
Thanks for the info.
I have several toroid wound mains transformers= and=20 wondered if they would be any use. A couple of persons have mentioned= using this=20 type on VLF.
I have a number of old LOPT cores and these wo= uld be more=20 suitable. I use these on 137 and 500 and they work well.
73 de mal/g3kev
 
----- Original Message -----
Sent: Sunday, February 20, 20= 11 7:22=20 PM
Subject: Re: LF: toroid xform= er

Dear Mal,
do not expect anything from laminated sh= eet iron=20 cores. Usable frequencxys depends on the thicknes of the Iron sheets= , and the=20 conductivity ot the material. Therefore the iron is alloyed with sil= icon and=20 aluminium, to reduce edding currents. Best frequ. for Mains transfor= mers is=20 200 Hz, with superior sheet iron 400 Hz. Toroid cores from vitrous= glasses=20 would be best, but are not available, only as catalog numbers at=20 Vacuumschmelze Hanau or Arnold, Micrometals and other manufacturers= of=20 materials. They do not offer kits with cores and coilformers . This= problem is=20 widely discussed in students lessons of the type "Maxwells equations= and the=20 transformer with laminated Iron core. "

55, Hans-Albrecht
= DK 8=20 ND
Von: "mal hamilton" <g3kevmal@talktalk.net>
Ges= endet:=20 20.02.2011 16:18:01
An: rsgb=20 <rsgb_lf_group@blacksheep.org>
Betreff: LF: toroid= =20 xformer

LF
Has anyone measured the ef= ficiency of=20 a mains toroid xformer on 9 Khz. I have some of these which could= be=20 useful.
ie 230v Prim and 6/12/24= v Sec, rated=20 10A at 12v
 
de mal/g3kev
 
  
3D""
NEU:=20 FreePhone - kostenlos mobil telefonieren und surfen!=20    
Jetzt informieren: http://produkte.web.de/go= /webdefreephone
<= /HTML> ------=_NextPart_000_0010_01CBD1AC.EA746DB0--