Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-ma06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1E530380000A4; Wed, 11 Jan 2012 16:42:09 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Rl5v5-00053B-Bo for rs_out_1@blacksheep.org; Wed, 11 Jan 2012 21:41:19 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Rl5v5-000532-0d for rsgb_lf_group@blacksheep.org; Wed, 11 Jan 2012 21:41:19 +0000 Received: from smtpout2.wanadoo.co.uk ([80.12.242.42] helo=smtpout.wanadoo.co.uk) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Rl5v2-0004MG-Dy for rsgb_lf_group@blacksheep.org; Wed, 11 Jan 2012 21:41:18 +0000 Received: from computereebf79 ([95.144.116.67]) by mwinf5d30 with ME id LMhA1i00E1TKQcn03MhAJt; Wed, 11 Jan 2012 22:41:11 +0100 Message-ID: <757BA00953CD4D3BBA2364F3E5A6156A@computereebf79> From: "Martin Evans" To: References: <593F4C0651144C339855AFC49ED4329E@computereebf79> <4F0DFFB1.8040509@iup.uni-heidelberg.de> Date: Wed, 11 Jan 2012 21:41:08 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 X-Spam-Score: 3.4 (+++) X-Spam-Report: autolearn=disabled,FORGED_MUA_OUTLOOK=3.36 Subject: Re: LF: Tuning inductance for 137kHz receive. Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.6 required=5.0 tests=FORGED_MUA_OUTLOOK 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: 0:2:409312768:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d600e4f0e02313ae1 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Thanks Stefan - this is what I feared. Guess that I'll have to be more conventional! I did look for you earlier this evening, but couldn't see your signal. I hope your new FETs arrive tomorrow. Martin. GW3UCJ. ############################# > The L will be much to high and the Q will be very low (=lossy). Also it > has a high parsitic C and will have a self resonance below 137 kHz. So > it rather acts like a capacitor. > > BTW capacitor, this is what i suggest. Simply use the 2 mH and a small > variable capacitor connected to the wire and GND. Then you can > accurately adjust to LF. > 73, GL, Stefan/DK7FC >