Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mp06.r1000.mx.aol.com (Internet Inbound) with ESMTP id BA38F380004D8; Tue, 18 Dec 2012 17:16:08 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Tl5RM-0006xN-VX for rs_out_1@blacksheep.org; Tue, 18 Dec 2012 22:15:08 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Tl5RM-0006xE-DV for rsgb_lf_group@blacksheep.org; Tue, 18 Dec 2012 22:15:08 +0000 Received: from mail-ie0-f180.google.com ([209.85.223.180]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1Tl5RK-0005IN-Fy for rsgb_lf_group@blacksheep.org; Tue, 18 Dec 2012 22:15:07 +0000 Received: by mail-ie0-f180.google.com with SMTP id c10so1700853ieb.39 for ; Tue, 18 Dec 2012 14:14:44 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; bh=o9ZbmrV6Kmy2UtUAJZAeb+mYMGZgmsprYpzlfKwLOBc=; b=ZJTDDoJ/8QhlNup2FhXyn4ejmTLj3i8Q0gYWjYzRRxWYVkZyjXXIH2j8VEN9hBSDTl ylVc8VjJZKUMHpUD/giz/5+MeGT6OZ8DKS3WwQDdR9yfo3ZMYt2wm9FWUi+9ZbVmEafo lTpqoqGLJYcZao+DUfq5q53Kp70BiQezOFpBQ0tCqsNZT71ZGk+kUKOdQYuo8g0II/xZ BjUZdTPNQuM/gZzQK0Celcl6FG3/2NVu0tEZzfu3JjNZ8j9LARQQR46paJhLoHmdYlKR 4SAF72ddKsC4tjYfuygkdQw4A0vIXrFsDVh9lI5gXYjqhlOVxtvktmqM1sg/6uY+eLL+ Ui3A== MIME-Version: 1.0 Received: by 10.42.32.71 with SMTP id c7mr4217141icd.35.1355868884390; Tue, 18 Dec 2012 14:14:44 -0800 (PST) Received: by 10.231.157.74 with HTTP; Tue, 18 Dec 2012 14:14:44 -0800 (PST) In-Reply-To: <50D0E412.8070403@iup.uni-heidelberg.de> References: <20121218092921.Horde.h2yZX_rSz0VQ0BtRPVIC2uA@posti.anvianet.fi> <20121218100332.Horde.2ASBc_rSz0VQ0CNU8mNkBhA@posti.anvianet.fi> <20121218152622.Horde.XfcUIerSz0VQ0G7_VqKUnlA@posti.anvianet.fi> <50D0E412.8070403@iup.uni-heidelberg.de> Date: Wed, 19 Dec 2012 09:14:44 +1100 Message-ID: From: Dimitrios Tsifakis To: rsgb_lf_group@blacksheep.org 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: Hi Stefan, I am also not part of the tube generation (born in the seventies) but I am fascinated by them! While a class-E PA is a very sensible and efficient PA, tubes (or valves) have a different kind of appeal to me. My 40 m transmitter is based on more than 50% recycled material which dates back to the 40s and 50s. The knobs and panel meters are from an old 30 kW AWA ISB transmitter. The 807 I am currently using (not the one in the photos) is an old soviet one, the 6CL6 comes from an old TV, the sockets from an old amateur boat anchor etc... [...] 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 [209.85.223.180 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (dtsifakis[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 66d07794ca19cd68f7d6cc289cd4ac18 Subject: Re: LF: Better picture of the 807 based 500kHz TX Content-Type: text/plain; charset=ISO-8859-1 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=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-global-disposition: G X-AOL-SCOLL-AUTHENTICATION: mtain-mp06.r1000.mx.aol.com ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1dc14a50d0eb2848b5 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Hi Stefan, I am also not part of the tube generation (born in the seventies) but I am fascinated by them! While a class-E PA is a very sensible and efficient PA, tubes (or valves) have a different kind of appeal to me. My 40 m transmitter is based on more than 50% recycled material which dates back to the 40s and 50s. The knobs and panel meters are from an old 30 kW AWA ISB transmitter. The 807 I am currently using (not the one in the photos) is an old soviet one, the 6CL6 comes from an old TV, the sockets from an old amateur boat anchor etc... Anyway, I do plan to use a class-E PA for my QRSS transmissions on LF/MF ;-= ) 73, Dimitris 2012/12/19 Stefan Sch=E4fer : > Hi Dimitris, > > Tubes for PAs is not my world (generation) but the topic is most interest= ing > and the webpage too. > > Good luck and i hope to see some traces from you some time, at constructi= ve > QSB :-) > > 73, Stefan/DK7FC > > Am 18.12.2012 22:07, schrieb Dimitrios Tsifakis: > >> By the way, here is my current 40 m 807 transmitter.This was the first >> attempt at building a valve TX. >> >> people.physics.anu.edu.au/~dxt103/valves/807/ >> >> I will use the same type of chassis for the 472 kc version but I will >> use an old 450-0-450 (50 mA), transformer which also has a 225-0-225 >> and 6.3 windings, for a more compact result. My hope is that I can >> draw a bit more than 50 mA without overheating the transformer and is >> based on the fact that CW is not 100% duty cycle and also I am not >> using the other windings to their maximum current ratings. >> >> 73, Dimitris VK1SV >> > >