Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dh02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1D7C5380000BA; Tue, 5 Feb 2013 04:15:54 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1U2eak-0007mN-EQ for rs_out_1@blacksheep.org; Tue, 05 Feb 2013 09:13:26 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1U2eaj-0007mE-W6 for rsgb_lf_group@blacksheep.org; Tue, 05 Feb 2013 09:13:25 +0000 Received: from mout.web.de ([212.227.15.3]) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1U2eai-0006Ix-7N for rsgb_lf_group@blacksheep.org; Tue, 05 Feb 2013 09:13:24 +0000 Received: from 3capp-webde-bs04.server.lan ([172.19.170.4]) by mriweb.server.lan (mriweb001) with ESMTPA (Nemesis) id 0LehGa-1Uk0Lw45Nu-00qNGM for =?utf-8?q??= =?utf-8?q?;?= Tue, 05 Feb 2013 10:13:02 +0100 Received: from [78.55.3.1] by 3capp-webde-bs04.server.lan with HTTP; Tue Feb 05 10:13:02 CET 2013 MIME-Version: 1.0 Message-ID: From: "Eike Katzera" To: rsgb_lf_group@blacksheep.org Date: Tue, 5 Feb 2013 10:13:02 +0100 (CET) Importance: normal Sensitivity: Normal In-Reply-To: <5110C6B8020000FA0001897D@gw1.sron.nl> References: , <5110C6B8020000FA0001897D@gw1.sron.nl> X-UI-Message-Type: mail X-Priority: 3 X-Provags-ID: V03:K0:fNbIxTOBwbCUK1DVWU0C2NkAR3ahde/NvG/jLQgZEDG TcMszhxTkuXayKQv0ydL3lz5WBvB+CNwcEeUmoWpnYbTtvwtrC 2ADE+YFcchpTt/GxMeOkMH1MCSBNoNehlCrjAf6emAQHTjdY0W /PIO1WDluGdbZCximA+H8bNoLCl3k1TMWXr3+ujr3ylxd8swas Hy5Hlth6ZFGP8uWY5EEr/ObDedPhuaV9iYrcDEO5mToFQ8/owk uJSK3Be/r9kj1h1Ifj5UzvjC4yJHreU2/gDIb5Yc4Xj5rwjqPY QPKVrvx7Fyse+BICRp+/dG40+Ja X-Spam-Score: 1.1 (+) 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: Hi Dimitros, the pulse shape in this picture does not look good: http://people.physics.anu.edu.au/~dxt103/472/nltt/vk1sv-drain.jpg The reason seams to be the duty cycle at the gate. Please try to change R5 to a 100k potentiometer and trim it to a clean single Pilse an the drain. I solved the same problem tha way in my PA, wich killed my IRF540. Kind regards [...] Content analysis details: (1.1 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [212.227.15.3 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (dl3ike[at]web.de) -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 1.1 MIME_HTML_ONLY BODY: Message only has text/html MIME parts X-Scan-Signature: e6de17d69e46ff4ea8db042ef2cd7e46 Subject: Aw: Re: LF: My transmit converter description Content-Type: text/html; charset=UTF-8 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=1.7 required=5.0 tests=HTML_30_40,HTML_MESSAGE, MIME_HTML_ONLY,PRIORITY_NO_NAME 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: 3039ac1d41165110cdc94628 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none
Hi Dimitros,
the pulse shape in this picture does not look good: http://people.physics.anu.edu.au/~dxt103/472/nltt/vk1sv-drain.jpg
The reason seams to be the duty cycle at the gate. Please try to change R5 to a 100k potentiometer and trim it to a clean single Pilse an the drain. I solved the same problem tha way in my PA, wich killed my IRF540.
Kind regards
Eike DL3IKE
PS: sorry for my english ;)
Gesendet: Dienstag, 05. Februar 2013 um 08:45 Uhr
Von: "Victor van Kooten" <V.A.G.van.Kooten@sron.nl>
An: rsgb_lf_group@blacksheep.org
Betreff: Re: LF: My transmit converter description
Looks very nice Dimitris,hope to see/hear you soon,

73

Victor

>>> Dimitrios Tsifakis <dtsifakis@gmail.com> 05/02/2013 01:50 >>>
Hello group,

My transmit converter is now finished and tested - it survived two
sessions of 50% duty cycle WSPR transmissions on 475 kHz and the
results are great. I thought others may find this useful, so I have
put a write-up on my web page:

http://people.physics.anu.edu.au/~dxt103/472/nltt/

It is a 50 W class-e PA designed for 50 ohm impedance, so there is no
need for an impedance transformer. Doesn't get simpler than that :-)
The driving circuit is based on G3XBM Roger's design with the
difference of a 10 MHz OCXO LO and the addition of a beefy MOSFET
driver.

73, Dimitris VK1SV