Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dh06.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1D9D63800009A; Mon, 11 Jun 2012 07:55:39 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Se3CQ-0005zv-P9 for rs_out_1@blacksheep.org; Mon, 11 Jun 2012 12:54:22 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Se3CQ-0005zm-6s for rsgb_lf_group@blacksheep.org; Mon, 11 Jun 2012 12:54:22 +0100 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1Se3CO-0003Ss-C7 for rsgb_lf_group@blacksheep.org; Mon, 11 Jun 2012 12:54:21 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id q5BBsJs2004926 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 11 Jun 2012 13:54:19 +0200 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id q5BBsI6L004372 for ; Mon, 11 Jun 2012 13:54:18 +0200 Message-ID: <4FD5DC0A.6040804@iup.uni-heidelberg.de> Date: Mon, 11 Jun 2012 13:52:42 +0200 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <169445B98101449D93BF2125A7343EF1@lindavideo> In-Reply-To: <169445B98101449D93BF2125A7343EF1@lindavideo> 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 Ken, Recently i have discovered a very nice to read paper in the web. Current mode class D PAs are described. The basics are well explained as well as how to calculate the power from the supply voltage (ideal and real). I think this is a good choice for a class D PA on 137 and 500 kHz... Hope this helps a bit. [...] 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 [129.206.100.212 listed in list.dnswl.org] -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: c95b9a52470b89d54f2ef38e923e05cb Subject: Re: LF: Class d & E PAs Content-Type: multipart/alternative; boundary="------------080701060907070204030804" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.2 required=5.0 tests=HTML_50_60,HTML_MESSAGE 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: 1:2:493809408:93952408 X-AOL-SCOLL-URL_COUNT: 1 x-aol-sid: 3039ac1d411a4fd5dcbb6f78 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. --------------080701060907070204030804 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello Ken, Recently i have discovered a very nice to read paper in the web. Current mode class D PAs are described. The basics are well explained as well as how to calculate the power from the supply voltage (ideal and real). I think this is a good choice for a class D PA on 137 and 500 kHz... Hope this helps a bit. 73, Stefan/DK7FC PS: http://sigma.ucsd.edu/research/articles/2001/2001_2.pdf PPS: A class E PA is a nice circuit but needs a very accurate SWR and construction can be a bit tricky. However i built one for 1 kW on 137 kHz at 80 VDC with 96% efficiency by using a single IRFP360... Am 10.06.2012 22:28, schrieb Ken: > > Dear All. > > Thank you for your help on the DECCA info, so far I have not tried a > Class D or E PA , my 500kHz TX having a power MOSFET in pseudso Class > C, with Class D & E how is the PA output impedance calculated, for the > output transformer, would it be permitted to use either a Pi or L-C_L > (as I have done) to match the PA to the variometer and loading coil? . > > 73s > > Ken > > M0KHW > --------------080701060907070204030804 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello Ken,

Recently i have discovered a very nice to read paper in the web. Current mode class D PAs are described. The basics are well explained as well as how to calculate the power from the supply voltage (ideal and real). I think this is a good choice for a class D PA on 137 and 500 kHz...
Hope this helps a bit.

73, Stefan/DK7FC

PS: http://sigma.ucsd.edu/research/articles/2001/2001_2.pdf
PPS: A class E PA is a nice circuit but needs a very accurate SWR and construction can be a bit tricky. However i built one for 1 kW on 137 kHz  at 80 VDC with 96% efficiency by using a single IRFP360...

Am 10.06.2012 22:28, schrieb Ken:

Dear All.

Thank you for your help on the DECCA info, so far I have not tried a Class D or E PA , my 500kHz TX having a power MOSFET in pseudso Class C, with Class D & E how is the PA output impedance calculated, for the output transformer, would it be permitted to use either a Pi or L-C_L (as I have done) to match the PA to the variometer and loading coil? .

 

73s

 

Ken

 

M0KHW

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