Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mp03.r1000.mx.aol.com (Internet Inbound) with ESMTP id E14B1380000B7; Tue, 16 Aug 2011 12:35:52 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QtMbb-0003ar-3F for rs_out_1@blacksheep.org; Tue, 16 Aug 2011 17:35:07 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QtMba-0003ai-KC for rsgb_lf_group@blacksheep.org; Tue, 16 Aug 2011 17:35:06 +0100 Received: from out1.ip03ir2.opaltelecom.net ([62.24.128.239]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QtMbY-0000X5-8O for rsgb_lf_group@blacksheep.org; Tue, 16 Aug 2011 17:35:06 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgEFAK+bSk5Ok80o/2dsb2JhbABBlGUDk1V4gTcEFAEBA0kCLAIIAgEGAR05AQQaBhgMHQECAgEBh2GYcKBRhkgEhzCcWA X-IronPort-AV: E=Sophos;i="4.68,234,1312153200"; d="scan'208,217";a="357062681" Received: from host-78-147-205-40.as13285.net (HELO xphd97xgq27nyf) ([78.147.205.40]) by out1.ip03ir2.opaltelecom.net with SMTP; 16 Aug 2011 17:34:58 +0100 Message-ID: <005f01cc5c32$66a39ae0$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: "rsgb" Date: Tue, 16 Aug 2011 17:34:41 +0100 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: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: ferrite coil Content-Type: multipart/alternative; boundary="----=_NextPart_000_005C_01CC5C3A.C7F59200" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.8 required=5.0 tests=HTML_30_40,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-SCORE: 0:2:280128704:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1dc1474e4a9c67732a X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ------=_NextPart_000_005C_01CC5C3A.C7F59200 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Jim es Co Instead of winding a tight coil on to a ferrite rod to get 270 uH and = tuning with a 250 p variable capacitor, instead wind an air core coil = and move the ferrite rod into/out of coil for the required inductance = necessary for frequency of interest. This would further reduce losses. Coil former just sufficient inner diameter to accommodate ferrite rod(s) = so size is virtually the same. mal/g3kev ------=_NextPart_000_005C_01CC5C3A.C7F59200 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Jim es Co
Instead of winding a tight coil on to a ferrite = rod to get=20 270 uH and tuning with a 250 p variable capacitor, instead wind an air = core coil=20 and move the ferrite rod into/out of coil for the required inductance = necessary=20 for frequency of interest. This would further reduce = losses.
Coil former just sufficient inner diameter to = accommodate=20 ferrite rod(s) so size is virtually the same.
 
mal/g3kev
 
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