Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-db04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 007B938000090; Tue, 18 Dec 2012 19:15:50 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Tl7JJ-0007vT-DR for rs_out_1@blacksheep.org; Wed, 19 Dec 2012 00:14:57 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Tl7JJ-0007vK-0B for rsgb_lf_group@blacksheep.org; Wed, 19 Dec 2012 00:14:57 +0000 Received: from smtpout2.wanadoo.co.uk ([80.12.242.42] helo=smtpout.wanadoo.co.uk) by relay1.thorcom.net with esmtp (Exim 4.77) (envelope-from ) id 1Tl7JH-0005lu-F4 for rsgb_lf_group@blacksheep.org; Wed, 19 Dec 2012 00:14:55 +0000 Received: from AGB ([2.26.47.56]) by mwinf5d26 with ME id dCEZ1k00N1CjwNS03CEZdr; Wed, 19 Dec 2012 01:14:34 +0100 Message-ID: <9E879884664540C8BC7A08377EAFC51C@AGB> From: "Graham" To: References: <20121218092921.Horde.h2yZX_rSz0VQ0BtRPVIC2uA@posti.anvianet.fi><20121218100332.Horde.2ASBc_rSz0VQ0CNU8mNkBhA@posti.anvianet.fi><20121218152622.Horde.XfcUIerSz0VQ0G7_VqKUnlA@posti.anvianet.fi><83EEBFC65ED94B0880138E0637A84E24@AGB> In-Reply-To: Date: Wed, 19 Dec 2012 00:14:33 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 X-Spam-Score: 0.2 (/) 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: lol well that config is for linear service , you should have the screen fed via something like 6.8K from the plate supply , with a 0.1 uF decoupling cap , no regulation for class C as the screen voltage will vary as the anode amps / secondary emission changes [ negative resistance type of thing] , you need a 100 ohm 2 watt resistor , shorted with a over wound 8 turn 10 mm id coil directly to the anode as acp , would normally have 50/100 ohms in series with the cathode as auto bias , should the drive fail, or IA = inf very quickly ... starts off with orange anodes by the wire supports , then yellow , then sparks inside , then white anodes , then glass shatters / melts = game over , with cathode keying , looking at a big gap cw key ! [...] Content analysis details: (0.2 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [80.12.242.42 listed in list.dnswl.org] 0.2 STOX_REPLY_TYPE STOX_REPLY_TYPE X-Scan-Signature: 7001055fa59a9c23b9831ea6d317a074 Subject: Re: LF: Better picture of the 807 based 500kHz TX Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original 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=0.1 required=5.0 tests=MISSING_OUTLOOK_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: 3039ac1d405850d107367fd9 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none lol well that config is for linear service , you should have the screen fed via something like 6.8K from the plate supply , with a 0.1 uF decoupling cap , no regulation for class C as the screen voltage will vary as the anode amps / secondary emission changes [ negative resistance type of thing] , you need a 100 ohm 2 watt resistor , shorted with a over wound 8 turn 10 mm id coil directly to the anode as acp , would normally have 50/100 ohms in series with the cathode as auto bias , should the drive fail, or IA = inf very quickly ... starts off with orange anodes by the wire supports , then yellow , then sparks inside , then white anodes , then glass shatters / melts = game over , with cathode keying , looking at a big gap cw key ! Happy days : ) G.. -------------------------------------------------- From: "Dimitrios Tsifakis" Sent: Tuesday, December 18, 2012 11:46 PM To: Subject: Re: LF: Better picture of the 807 based 500kHz TX > 2012/12/19 Graham : >> Why the stabilised screen supply ? >> G.. > > It's embarassing. I like the glow of VR tubes! :-) > > 73, Dimitris VK1SV >