Return-Path: Received: (qmail 28612 invoked from network); 15 Mar 2001 22:20:38 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by extortion.plus.net with SMTP; 15 Mar 2001 22:20:38 -0000 Received: (qmail 8565 invoked from network); 15 Mar 2001 22:20:35 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 15 Mar 2001 22:20:35 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14dg24-0005aY-00 for rsgb_lf_group-outgoing@blacksheep.org; Thu, 15 Mar 2001 22:15:44 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from anchor-post-32.mail.demon.net ([194.217.242.90]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14dg23-0005aS-00 for rsgb_lf_group@blacksheep.org; Thu, 15 Mar 2001 22:15:44 +0000 Received: from pickmere.demon.co.uk ([158.152.117.143]) by anchor-post-32.mail.demon.net with smtp (Exim 2.12 #1) id 14dg1i-0006XM-0W for rsgb_lf_group@blacksheep.org; Thu, 15 Mar 2001 22:15:23 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Message-ID: Date: Thu, 15 Mar 2001 19:15:16 +0000 To: rsgb_lf_group@blacksheep.org From: "M.J.Powell" Subject: Re: LF: Tube EF50 References: <004901c0ad60$39936300$1fd725c3@194.95.193.10.fen.baynet.de> <3.0.5.32.20010315161208.0082a100@pop3.esoterica.pt> In-reply-to: <3.0.5.32.20010315161208.0082a100@pop3.esoterica.pt> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=iso-8859-1; format=flowed X-Mailer: Turnpike Integrated Version 4.02 S Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: In message <3.0.5.32.20010315161208.0082a100@pop3.esoterica.pt>, Brian Rogerson writes >I'm sorry, I could not resist. 73, Brian > >At 15:55 15/03/01 +0100, you wrote: >>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. That's the normal method, but when used in the H2S equipment, after the Tx pulse the Rx was used in high gain mode, with a few plus volts on the g3 to catch the first ground return. Mike -- M.J.Powell