Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-db04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 3740138000083; Sun, 4 Mar 2012 08:24:43 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1S4BPd-0007zj-DW for rs_out_1@blacksheep.org; Sun, 04 Mar 2012 13:23:45 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1S4BPc-0007za-TK for rsgb_lf_group@blacksheep.org; Sun, 04 Mar 2012 13:23:44 +0000 Received: from relay2.uni-heidelberg.de ([129.206.210.211]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1S4BPa-0001nb-Ii for rsgb_lf_group@blacksheep.org; Sun, 04 Mar 2012 13:23:44 +0000 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay2.uni-heidelberg.de (8.13.8/8.13.8) with ESMTP id q24DNfl3018781 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sun, 4 Mar 2012 14:23:42 +0100 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id q24DNfPT012504 for ; Sun, 4 Mar 2012 14:23:41 +0100 Message-ID: <4F536CA6.6050702@iup.uni-heidelberg.de> Date: Sun, 04 Mar 2012 14:22:46 +0100 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= 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: <201203041002510911.100078C7@smtp2.numeo.fr> <4F534D1B.1050901@iup.uni-heidelberg.de> <46C9653A-4685-4482-BB81-49E9FCD0C001@numeo.fr> In-Reply-To: <46C9653A-4685-4482-BB81-49E9FCD0C001@numeo.fr> X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: Short burst of DK7FC on 137 Content-Type: text/plain; charset=ISO-8859-1; format=flowed 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=0.0 required=5.0 tests=none 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: 0:2:501570368:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d40584f536d1b2385 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hi John, Am 04.03.2012 13:35, schrieb John Rabson: > You recently mentioned that you were using an H-Bridge amplifier for > 137, but I seem to have lost the details. Could you post them again, > please? I am finding that I am rather good at blowing up class E PAs > and think I should look for something that is rather more robust (and > more tolerant of variations in load isimpedance). Well i have done some drawings and pictures in the last time, concerning my PA and LPF and matching system. Here they are: http://dl.dropbox.com/u/19882028/LF/DK7FC_137kHz_TX_antenna_and_PA_schematic.jpg http://dl.dropbox.com/u/19882028/LF/PA%20output%20filter.jpg Hm, sorry i'm missing the photo of the drawing of the exciter. I know i have it on a sheet but maybe i forgot to scan it. Will so that next week. Pse ask me agn if i forget it. BTW the blue output transformer in the photo handles at least 1.5 kW CW at 137 kHz. Usually if people ask what type of ferrite is used in a PA, the answer is like "it is taken from a SMPS or old TV and unknown origin", "found it in the junkbox"... But here i know the exact type and even a distributor and even the price! ;-) It is even avaialable in quantity = 1 :-) It is a B64290L0699X830. Datasheet: http://dl.dropbox.com/u/19882028/Datenbl%C3%A4tter/B64290L699X830.pdf (page 3) Available e.g. @ https://www.buerklin.com/default.asp?event=ShowArtikel(84D258)&l=d&jump=ArtNr_84D258 for 10 Euro :-) 73, Stefan/DK7FC