Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id v4PCEJpP009406 for ; Thu, 25 May 2017 14:14:20 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1dDrZw-0006fk-NU for rs_out_1@blacksheep.org; Thu, 25 May 2017 13:09:20 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1dDrZw-0006fb-Dt for rsgb_lf_group@blacksheep.org; Thu, 25 May 2017 13:09:20 +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 4.89) (envelope-from ) id 1dDrZt-0007gb-Cv for rsgb_lf_group@blacksheep.org; Thu, 25 May 2017 13:09:19 +0100 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id 50F952082C for ; Thu, 25 May 2017 14:09:16 +0200 (CEST) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3wYSjl2SlQz106N for ; Thu, 25 May 2017 14:09:15 +0200 (CEST) Message-ID: <5926C96B.7050206@posteo.de> Date: Thu, 25 May 2017 14:09:15 +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: <1456380282.20170524154713@gmail.com> <5925A16B.7050100@posteo.de> <48702557.20170525114046@gmail.com> In-Reply-To: <48702557.20170525114046@gmail.com> X-Scan-Signature: c1f72e5acb1277e013f90c915ad7ad68 Subject: Re: LF: Iron dust toroids and heating Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit 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 2.75 Status: O X-Status: X-Keywords: X-UID: 11761 Hi Chris, Am 25.05.2017 12:40, schrieb Chris Wilson: > I was wondering if the #3 material which is rated for use from 0.05 to > 0.5 MHz, and has several times the permeability would be a better > choice for more power through it? It probably gives a higher Q with > fewer turns, allowing the use of larger wire without having > overlapping layers in the winding? > Yes that sounds like a good concept. It is interesting to follow your plans. Actuelly i would like to try to build a 2.5 kW or larger PA as well, just for interest of course. I would of course use it together with a dummy load only, because you must not radiate more than 1 W here in DL, and i am a conformist and under the spell of authorities (german: autoritätshörig) :-) It would be interesting to deal with the problems that would appear with such PAs. For say 3 kW and the comfortable situation to have a suitable 60 V power supply, i would simply build a current mode class D PA, hard keyed with an IXDD614CI and 2x 4x IRFP260N FETs. For the LPF i would use the T225A-2 together with RF litz wire, maybe 250x0.1mm, available at https://www.spulen.com/hf-litze-250-x-0-1-mm-100-g-spule.html and WIMA-FKP-1 capacitors, the 2 kV version... Good luck and fun with your projects. 73, Stefan