Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mc05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 137673800009F; Wed, 8 Aug 2012 18:05:31 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SzELu-0004lD-QI for rs_out_1@blacksheep.org; Wed, 08 Aug 2012 23:03:42 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SzELt-0004l4-VT for rsgb_lf_group@blacksheep.org; Wed, 08 Aug 2012 23:03:41 +0100 Received: from mail-yw0-f43.google.com ([209.85.213.43]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1SzELs-0003rC-CD for rsgb_lf_group@blacksheep.org; Wed, 08 Aug 2012 23:03:40 +0100 Received: by yhl10 with SMTP id 10so2690073yhl.16 for ; Wed, 08 Aug 2012 15:03:37 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=uI8rzE8YyIBcYNIeFy5Zqv7Xv9qluy+pKgCqOmJKsos=; b=R2mWGaS1U2I8TQMhZAvQigXzZOkCfh6tfPK8VlOxvvbdGXS53kQcfvbVGr0/H03NCg 1+cUi4cLKLLn5Lu/OFOdPRIpklJTU/nW1or7VztyaEpaYgPZkSErhNpzPqfwQcgSg1hm 0aalOoO3M79jdrcMul2Hb/GZHcnQVWj/LP5paYrs7x24zBJofOsjWtrWvXeeKsdl8KIE bI78+2c1oEc0PXNz5MQmX1r/CjTEz7jdWmMGU6Fx97vtyw+7YFFE1zxzY/oA0yvSHRVJ tMMipJNTcrWCwZj+7Uheb13r7nmM3+DCL7gPh20XDfxOi3QB8GSYn2rCQm984U75JSPr RTgA== MIME-Version: 1.0 Received: by 10.60.20.233 with SMTP id q9mr33039079oee.57.1344463417745; Wed, 08 Aug 2012 15:03:37 -0700 (PDT) Received: by 10.182.39.10 with HTTP; Wed, 8 Aug 2012 15:03:37 -0700 (PDT) Date: Thu, 9 Aug 2012 08:03:37 +1000 Message-ID: From: Dimitrios Tsifakis To: rsgb_lf_group@blacksheep.org X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hello LF group, I am building a 200 W Class-E transmitter for LF but keep killing the capacitors in the output circuit (both C1 and C2 according to the schematic in Sokal's QST article). I have used a mixture WIMA polypropylene MKP10, MKP4 and FKP1 caps and I haven't damaged any FKP ones so far. Should I not bother with MKP and use only FKP caps or is there any other type of capacitor what will do the job? I need a couple of hundred of nanofarads. The voltage rating of the caps I destroyed was 400 VDC or 250 VAC. I can see that these caps have a decreasing AC rating as the frequency goes up, but that's what I had in the junk box at the time... [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.213.43 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (dtsifakis[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 4ead635eadbaebfaa92cfec77deb715d Subject: LF: Caps for Class-E amp Content-Type: text/plain; charset=ISO-8859-1 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: 0:2:483576256:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d015.1 ; domain : gmail.com DKIM : fail x-aol-sid: 3039ac1d604d5022e2ab6ab4 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hello LF group, I am building a 200 W Class-E transmitter for LF but keep killing the capacitors in the output circuit (both C1 and C2 according to the schematic in Sokal's QST article). I have used a mixture WIMA polypropylene MKP10, MKP4 and FKP1 caps and I haven't damaged any FKP ones so far. Should I not bother with MKP and use only FKP caps or is there any other type of capacitor what will do the job? I need a couple of hundred of nanofarads. The voltage rating of the caps I destroyed was 400 VDC or 250 VAC. I can see that these caps have a decreasing AC rating as the frequency goes up, but that's what I had in the junk box at the time... The mode of failure of these MKP10 0.1 400 VDC caps is interesting too, they seem to go down in capacitance as the damage progresses. Any advice is appreciated. 73, Dimitris VK1SV/SV1DET