Return-Path: Received: from rly-da09.mx.aol.com (rly-da09.mail.aol.com [172.19.129.83]) by air-da03.mail.aol.com (v126.13) with ESMTP id MAILINDA032-a904b4c595ad4; Tue, 12 Jan 2010 06:13:51 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-da09.mx.aol.com (v125.7) with ESMTP id MAILRELAYINDA098-a904b4c595ad4; Tue, 12 Jan 2010 06:13:32 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NUefw-00006q-HQ for rs_out_1@blacksheep.org; Tue, 12 Jan 2010 11:12:40 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NUefw-00006h-3Y for rsgb_lf_group@blacksheep.org; Tue, 12 Jan 2010 11:12:40 +0000 Received: from out1.ip05ir2.opaltelecom.net ([62.24.128.241]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NUefu-0005Fb-31 for rsgb_lf_group@blacksheep.org; Tue, 12 Jan 2010 11:12:40 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AncFAM/nS0tOlCMj/2dsb2JhbACIJ811hDAE X-IronPort-AV: E=Sophos;i="4.49,261,1262563200"; d="scan'208";a="284944371" Received: from unknown (HELO your91hoehfy9g) ([78.148.35.35]) by out1.ip05ir2.opaltelecom.net with SMTP; 12 Jan 2010 11:12:31 +0000 Message-ID: <005001ca9378$224b4fc0$0301a8c0@your91hoehfy9g> From: "mal hamilton" To: References: <20100111090709.EAAFE31E706@smtps01.kuleuven.be> <4B4C1D36.3090707@telia.com> <38A51B74B884D74083D7950AD0DD85E82A1A94@File-Server-HST.hst.e-technik.tu-darmstadt.de> Date: Tue, 12 Jan 2010 11:12:31 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: PA0 into Alaska 600m Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit 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 I use a single ended E pa and it is vy robust. I use a good LPF and the 2nd harmonic is not a problem. mal/g3kev ----- Original Message ----- From: "Stefan Schäfer" To: Sent: Tuesday, January 12, 2010 10:42 AM Subject: AW: LF: PA0 into Alaska 600m Hi Johan, What are you planning? This sounds like QROO? Why using a push-pull class E stage when a single stange can do it? I am interested! :-) Stefan/DK7FC ________________________________ Von: owner-rsgb_lf_group@blacksheep.org im Auftrag von Johan H. Bodin Gesendet: Di 12.01.2010 07:56 An: rsgb_lf_group@blacksheep.org Betreff: Re: LF: PA0 into Alaska 600m Hi Andy, I tried to connect two class E stages in push-pull and it worked as expected. This was a QRP experiment on 160m but I see no reason why it shouldn't be scalable. The even harmonic cancellation of the symmetrical design is welcome since the drain waveform contains quite a lot of 2f. Each side is designed for half the output power into some R and then the matching transformer is designed to have 2R looking into the primary. The two series resonant tanks can be combined into a single one having half the C and twice the L (as in the attached picture). Who will be the first to try a QRO version of this amplifier? :-) 73 Johan SM6LKM Andy Talbot wrote: > All designs & ideas for a 1kW+ Class E PA gratefully accepted :-) > I do have a 50V 25A PSU, so it 'might' even be feasible. > > Two big meaty FETs in parallel may cope. There's an article in the > latest QEX, just arrived, that appears to run class E stages in parallel > - but its part of another concept, not targetted at high power /per-se/.