Return-Path: Received: (qmail 7567 invoked from network); 25 Feb 2005 23:35:39 -0000 Received: from unknown (HELO ptb-spamcore02.plus.net) (192.168.71.3) by ptb-mailstore03.plus.net with SMTP; 25 Feb 2005 23:35:39 -0000 Received: from mailnull by ptb-spamcore02.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1D4p0w-000B0g-El for dave@picks.force9.co.uk; Fri, 25 Feb 2005 23:36:55 +0000 Received: from [192.168.67.1] (helo=ptb-mxcore01.plus.net) by ptb-spamcore02.plus.net with esmtp (Exim 4.32; FreeBSD) id 1D4p0w-000B0d-BZ for dave@picks.force9.co.uk; Fri, 25 Feb 2005 23:36:54 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore01.plus.net with esmtp (Exim) id 1D4p1e-0007iW-ED for dave@picks.force9.co.uk; Fri, 25 Feb 2005 23:37:38 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1D4oz7-0000tg-JN for rs_out_1@blacksheep.org; Fri, 25 Feb 2005 23:35:01 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1D4oz7-0000tX-8I for rsgb_lf_group@blacksheep.org; Fri, 25 Feb 2005 23:35:01 +0000 Received: from smarthost1.mail.uk.easynet.net ([212.135.6.11]) by relay.thorcom.net with esmtp (Exim 4.43) id 1D4oz4-0008FX-Pv for rsgb_lf_group@blacksheep.org; Fri, 25 Feb 2005 23:35:01 +0000 Received: from tnt-2-138.easynet.co.uk ([195.40.196.138] helo=erica) by smarthost1.mail.uk.easynet.net with smtp (Exim 4.10) id 1D4oz0-000KOy-00 for rsgb_lf_group@blacksheep.org; Fri, 25 Feb 2005 23:34:55 +0000 Message-ID: <001901c51b74$9f4e6b00$8ac428c3@erica> From: "g3ldo" To: rsgb_lf_group@blacksheep.org References: <003e01c51b35$a09d30c0$fe79a8c0@PCVONWALTER> Date: Fri, 25 Feb 2005 19:59:32 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 X-SPF-Result: relay.thorcom.net: 212.135.6.11 is neither permitted nor denied by domain of ukonline.co.uk X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=failed,none Subject: LF: Re: 807s Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Status: No, hits=0.7 required=5.0 tests=DATE_IN_PAST_03_06 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-Spam-Filtered: by PlusNet SpamCORE (v3.00) From: "Walter Staubach" is "your" 807 the same tube as I remember: PA-tube, 6V heater, anode loss 25W, anode voltage 400 to 700V, penthode. It was used for homebrew transmitters, often with the GELOSO-VFO ( CW and AM only ). One connection ontop of the glass, I think that was anode. A rather big tube. If it is the same - why building a receiver with it? :-) The 807 was the most popular PA tube for HB in the 50s and 60s. They were plentiful and reasonably cheap and could handle a lot of misuse. They were tetrodes with an anode (plate) topcap.With a maximum PA voltage of around 750v and a current of 100mA they could put out around 40 or 50w. I used a couple of 1625s (12.6v heater equivalent of the 807) in a zero bias pushpull high level modulator. The Geloso VFO was my first ever commercial ham radio purchase. I modified it by replacing the 6V6 driver with a QVO-47. I think the reason these high power tubes were used in receiver distribution amplifiers is that they operated in the linear portion of the curve no matter what large signal strength signals appeared in the passband. Nostalgia aint what it used to be! Peter G3LDO