Return-Path: Received: from rly-me07.mx.aol.com (rly-me07.mail.aol.com [172.20.83.41]) by air-me09.mail.aol.com (v120.9) with ESMTP id MAILINME091-9c5472dc1ec308; Sun, 04 Nov 2007 07:58:28 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-me07.mx.aol.com (v120.9) with ESMTP id MAILRELAYINME071-9c5472dc1ec308; Sun, 04 Nov 2007 07:58:22 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Iof3F-0007pS-Gb for rs_out_1@blacksheep.org; Sun, 04 Nov 2007 12:58:05 +0000 Received: from [193.82.59.130] (helo=relay2.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Iof3D-0007pJ-0R for rsgb_lf_group@blacksheep.org; Sun, 04 Nov 2007 12:58:03 +0000 Received: from sighthound.demon.co.uk ([80.177.174.126]) by relay2.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Iof3A-0004mg-OU for rsgb_lf_group@blacksheep.org; Sun, 04 Nov 2007 12:58:02 +0000 Received: from lurcher.twatt.local (lurcher.twatt.local [127.0.1.1]) by lurcher.twatt.local (Postfix) with ESMTP id 06B37DA4D9 for ; Sun, 4 Nov 2007 12:57:54 +0000 (GMT) Date: Sun, 4 Nov 2007 12:57:53 +0000 From: John Pumford-Green GM4SLV To: rsgb_lf_group@blacksheep.org Message-ID: <20071104125753.6c9e45a1@lurcher.twatt.local> In-Reply-To: <000701c81ede$3af050e0$1ae4fc3e@g3kev> References: <000701c81ede$3af050e0$1ae4fc3e@g3kev> Organization: The Gammy Bird X-Mailer: Claws Mail 2.10.0 (GTK+ 2.12.0; i486-pc-linux-gnu) Mime-Version: 1.0 X-Spam-Score: 0.3 (/) X-Spam-Report: autolearn=disabled,AWL=0.044,RCVD_ILLEGAL_IP=0.234 Subject: Re: LF: CLASS D and E Content-Type: text/plain; charset=US-ASCII 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-IP: 193.82.116.20 X-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_helo : X-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_822_from : On Sun, 4 Nov 2007 12:28:05 -0000 "hamilton mal" wrote: > Hi all > Class D and E amplifiers are supposed to give around 80/90 % > efficiency. Has anyone actually achieved these figures. It seems > anything above 60% is hard to arrive at using normal coils/capacitors. > > 73 de Mal/G3KEV > > Hello Mal & LF, The best I've acheived with Class-E has been about 70-75%. I understand that you're supposed to select values of components and tune the o/p stage for best efficiency at your chosen DC supply volts and target power. Away from these points the efficiency won't be optimum. 70% is easily acheived by careful tuning. 80% and better has eluded me so far. Cheers, John -- John GM4SLV IP90gg Clousta, Shetland