Return-Path: Received: from mtain-mk04.r1000.mx.aol.com (mtain-mk04.r1000.mx.aol.com [172.29.97.136]) by air-md10.mail.aol.com (v129.4) with ESMTP id MAILINMD101-8b984d3213cbe0; Sat, 15 Jan 2011 16:38:20 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mk04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 87845380000B8; Sat, 15 Jan 2011 16:38:18 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PeDo9-0004X6-0Z for rs_out_1@blacksheep.org; Sat, 15 Jan 2011 21:37:13 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PeDo8-0004Wx-9z for rsgb_lf_group@blacksheep.org; Sat, 15 Jan 2011 21:37:12 +0000 Received: from nm10.bullet.mail.ukl.yahoo.com ([217.146.182.251]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1PeDo7-0008Sl-64 for rsgb_lf_group@blacksheep.org; Sat, 15 Jan 2011 21:37:12 +0000 Received: from [217.146.183.210] by nm10.bullet.mail.ukl.yahoo.com with NNFMP; 15 Jan 2011 21:37:05 -0000 Received: from [217.146.183.170] by tm3.bullet.mail.ukl.yahoo.com with NNFMP; 15 Jan 2011 21:37:05 -0000 Received: from [127.0.0.1] by omp1011.mail.ukl.yahoo.com with NNFMP; 15 Jan 2011 21:37:05 -0000 X-Yahoo-Newman-Id: 526360.30820.bm@omp1011.mail.ukl.yahoo.com Received: (qmail 14988 invoked from network); 15 Jan 2011 21:37:05 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=btinternet.com; h=DKIM-Signature:Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE:X-Antivirus:X-Antivirus-Status; b=aPrh22KVXgG9bf+A75Q91/XS/tApR9OXULM1ezr0QYyNwCadeDdIuPj2kTtF4mRC/XhlHn+eX8wFKfJrTyFZKe/nOXumvlWpSkQu4+U3TUQUJfkXLE4ZhGGLNXPvJA7/5JLjvY9VJHgWeNx7IhnapcAr5z7p/CRRSuy8OzG1rIw= ; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=s1024; t=1295127425; bh=zL6WxlF6ci1vqq5AOXztpb4CSWzKfntrAUiISlRG834=; h=Received:X-Yahoo-SMTP:X-YMail-OSG:X-Yahoo-Newman-Property:Message-ID:From:To:References:Subject:Date:MIME-Version:Content-Type:Content-Transfer-Encoding:X-Priority:X-MSMail-Priority:X-Mailer:X-MimeOLE:X-Antivirus:X-Antivirus-Status; b=dENvBGE0l3x1HC3kpFnZVv+8au5RppFL187CMfzeChs9n9uZHtKzD+WoGcDsp0dqc/vIYxeZbeZ8xYla3C17e8pwtg41Ay/wsZzZzgzk3HnGWlfi0eT6sugpXkDkj1Bc5m0RDeEDrbz70tYLHsUDn4Ma0+qkuX9ePaHmla2MEYM= Received: from lark (alan.melia@86.157.31.254 with login) by smtp820.mail.ukl.yahoo.com with SMTP; 15 Jan 2011 21:37:02 +0000 GMT X-Yahoo-SMTP: fpz.2VeswBBs59bVshRPmMN51lcO2lgFRIvE4XTqE8dRwOxd70E- X-YMail-OSG: XUiAP80VM1lHtX8sXT6RNsUn9zb3M78p8uSN.kv5LwGeYqH QSwtGtx7vEu4O0fjla_og3YqqnfqaWjjLPF4dMxPsGlThtP55w6FNClyJy5D FZnsEOVRJWr1S0Q.aR7e6Hk6WMAiluSVZWW1EAinkycoTQ6i6wDqANtxnMla oHDRq4hL.pQ7hjPPfszI1MWDXY0MCEgAmcHLmz_v7mIeeVepPdVqJiy25SDq 3ptPqzOo38eU2wv1BNJz_7liK5FbpEnERCeh4Cie5Q1Rkikj1orZiQvv1t5g paQnG2nEWZRmlmCgA_0mrnBYVnjQB5CJkoAa2ggruWWewfQ-- X-Yahoo-Newman-Property: ymail-3 Message-ID: <001401cbb4fc$59b40780$4001a8c0@lark> From: "Alan Melia" To: "RSGB LF Gp" References: Date: Sat, 15 Jan 2011 21:36:55 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.2001 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.2001 X-Antivirus: avast! (VPS 110115-1, 15/01/2011), Outbound message X-Antivirus-Status: Clean DomainKey-Status: good (testing) X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,UNPARSEABLE_RELAY=0.001 Subject: LF: Re: Why do blown FETs always go Drain-Gate short? Content-Type: text/plain; charset="iso-8859-1" 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-AUTHENTICATION: mail_rly_antispam_dkim-d281.1 ; domain : btinternet.com DKIM : fail x-aol-sid: 3039ac1d61884d3213ca1ece X-AOL-IP: 195.171.43.25 I thnk that is the highest stress area (V/um), then the device it permanently on, so it takes a little longer to melt the silicon or fuse the source lead or both. Get rid of the burned epoxy smell?? Ah try zapping a selenium rectifer :-) you wont smell the epoxy after that. It works with tantalums as well. Alan G3NYK ----- Original Message ----- From: "Andy Talbot" To: Sent: Saturday, January 15, 2011 4:53 PM Subject: LF: Why do blown FETs always go Drain-Gate short? > And the Source leads either melt or blow out of the packaging > > Guess who lowered the drive freq on his class E PA without thinking. > > Still... > at least now the design is proven, and I know how easy it is it set up, will > order some IRFP360 devices and try for a modern higher efficiency version. > > How do you get rid of the smell of burnt epoxy :-( > > Andy > www.g4jnt.com >