Return-Path: Received: from mtain-dj06.r1000.mx.aol.com (mtain-dj06.r1000.mail.aol.com [172.19.187.142]) by air-da04.mail.aol.com (v129.4) with ESMTP id MAILINDA041-85e64d2b277e3b5; Mon, 10 Jan 2011 10:36:30 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dj06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 07192380000B5; Mon, 10 Jan 2011 10:36:27 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PcJmZ-0003TP-6k for rs_out_1@blacksheep.org; Mon, 10 Jan 2011 15:35:43 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PcJmY-0003TG-R2 for rsgb_lf_group@blacksheep.org; Mon, 10 Jan 2011 15:35:42 +0000 Received: from mhost02c.leeds.ac.uk ([129.11.76.154]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PcJmW-0000mX-9m for rsgb_lf_group@blacksheep.org; Mon, 10 Jan 2011 15:35:42 +0000 Received: from APOLLO2.ds.leeds.ac.uk (apollo2.leeds.ac.uk [129.11.5.5]) by mhost02c.leeds.ac.uk (8.14.3/8.14.3) with ESMTP id p0AFZKtH018848 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT) for ; Mon, 10 Jan 2011 15:35:34 GMT Received: from HERMES8.ds.leeds.ac.uk ([fe80::39ce:23e:d0b5:7e24]) by APOLLO2.ds.leeds.ac.uk ([129.11.5.5]) with mapi; Mon, 10 Jan 2011 15:35:30 +0000 From: Chris Trayner To: "rsgb_lf_group@blacksheep.org" Date: Mon, 10 Jan 2011 15:35:28 +0000 Thread-Topic: LF: Re: Capacitor warning and First 500kHz Class E breadboard Thread-Index: Acuw3AJcBRG7DmWqSPesLhCAP64zOQ== Message-ID: References: <004701cbb0d8$25d56e40$0401a8c0@xphd97xgq27nyf> In-Reply-To: Accept-Language: en-US, en-GB Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US, en-GB MIME-Version: 1.0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: Capacitor warning and First 500kHz Class E breadboard Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable 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=TO_ADDRESS_EQ_REAL 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-sid: 3039cdbc9d0b4d2b277b22dc X-AOL-IP: 195.171.43.25 X-Mailer: Unknown (No Version) Hi Andy, > I resurrected a 10n one from the waste bin, connected the C meter (10.9n= F at Room Temp) and turned a hair dryer on it. C reduced to 5.4nF as I= was watching, and that was probably only around 50C. =20 > Blowing on it shifted the value noticeably. I have a batch of very bad (high temp coef) 22nF I sometimes use for under= grad teaching. Get the students to build an oscillator with them, watch th= e waveform and then grip the cap between thumb and forefinger. You can see= the square wave width change visibly - you don't even need to measure it= to realise it's happening. 73, Chris G4OKW