Return-Path: Received: (qmail 13933 invoked from network); 15 Mar 2001 15:03:25 -0000 Received: from unknown (HELO murphys-inbound.servers.plus.net) (212.159.14.225) by excalibur.plus.net with SMTP; 15 Mar 2001 15:03:25 -0000 Received: (qmail 11094 invoked from network); 15 Mar 2001 15:03:02 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 15 Mar 2001 15:03:02 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14dZCM-0003Ax-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 15 Mar 2001 14:57:54 +0000 Received: from hugo.fen-net.de ([194.95.193.10] ident=root) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14dZCL-0003As-00 for rsgb_lf_group@blacksheep.org; Thu, 15 Mar 2001 14:57:53 +0000 Received: from 194.95.193.10.fen.baynet.de (dialin-nbg-190.fen-net.de [195.37.215.70]) by hugo.fen-net.de (8.9.1/8.9.1) with SMTP id PAA25941 for ; Thu, 15 Mar 2001 15:57:14 +0100 (MET) Message-ID: <004901c0ad60$39936300$1fd725c3@194.95.193.10.fen.baynet.de> From: "Walter Staubach" To: "Reflektor" Subject: LF: Tube EF50 Date: Thu, 15 Mar 2001 15:55:22 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.72.3110.5 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from 8bit to quoted-printable by hugo.fen-net.de id PAA25941 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: With nostalgic smile I read the many mails about EF50 and other tubes that I used in the "tube-times" of my ham-life. Here some electrical data of it: (source: Röhren-Taschen-Tabelle Franzis-Verlag München 1964) The tube was used for HF- and wideband-amplification up to 50MHz. The amplification could be regulated by varying the negative voltage at grid 3 - says the book. This seems a little unbelievable to me, because mostly a variable voltage at grid1 was used. heater 6.3V - 0.3A / anode 250V 10mA / grid3 0..-54V / grid2 250V 3mA / grid1 -2V / resistor at cathode 600ohms. socket loctal, comparable type EF53. 73 Walter DJ2LF --------------------------------------------- Walter.Staubach@fen-net.de