Return-Path: X-Spam-DCC: paranoid 1169; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00 autolearn=unavailable version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id s68DiHgx006817 for ; Tue, 8 Jul 2014 15:44:17 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1X4Vb3-0007oB-LE for rs_out_1@blacksheep.org; Tue, 08 Jul 2014 14:38:13 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1X4Vb3-0007o0-CP for rsgb_lf_group@blacksheep.org; Tue, 08 Jul 2014 14:38:13 +0100 Received: from fw.cz.gmc.net ([194.212.10.23] helo=mail.cz.gmc.net) by relay1.thorcom.net with esmtps (TLSv1:RC4-MD5:128) (Exim 4.82) (envelope-from ) id 1X4Vb1-0004UH-Fl for rsgb_lf_group@blacksheep.org; Tue, 08 Jul 2014 14:38:12 +0100 Received: from CZ029PM (194.212.10.29) by mail.cz.gmc.net (192.168.47.18) with Microsoft SMTP Server (TLS) id 8.1.436.0; Tue, 8 Jul 2014 15:38:10 +0200 Message-ID: <0934B7A5CEF542C891BDBD0F188ECEE3@gmc.net> From: Petr Maly To: References: <9FE61D98573D45E08A39735EF283914F@gmc.net> <53BAE6E9.3050206@tele2.se> <1404795548.36812.YahooMailNeo@web173001.mail.ir2.yahoo.com> <1404815337.38505.YahooMailNeo@web173004.mail.ir2.yahoo.com> <1404815801.86408.YahooMailNeo@web173004.mail.ir2.yahoo.com> <20140708125015.7EB66444@for04.foreach.it> In-Reply-To: <20140708125015.7EB66444@for04.foreach.it> Date: Tue, 8 Jul 2014 15:44:12 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 16.4.3505.912 X-MimeOLE: Produced By Microsoft MimeOLE V16.4.3505.912 X-EsetResult: clean, is OK X-EsetId: 0A13AF3E7E8FD3DB5851F2 X-Scan-Signature: f38d515a9cad1e977fcfe251941a8120 Subject: LF: Re: Pure off-topic: old tubes Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit 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-Scanned-By: MIMEDefang 2.56 on 10.1.3.10 Status: O X-Status: X-Keywords: X-UID: 31 Hello Marco, You are so kind. Thank you very much. My tubes look exactly like 4B/551B(D). I will measure the dimensions to be sure as soon as I can. It looks convenient that the filament voltage is the usual 6.3 volts. Interesting is that they count with anode voltage as much as 10 or even 14 kV! Thanks again for your effort. 73, Petr, OK1FIG -----Original Message----- From: Marco IK1ODO -2 Sent: Tuesday, July 08, 2014 2:50 PM To: rsgb_lf_group@blacksheep.org Subject: Re: Fw: LF: Pure off-topic: old tubes 15 years ago I was used to buy truckloads of test and communication equipment from Johns Radio in Bradford (now he is in Batley). He had a lot of equipment from the closure of STC R&D labs. I acquired many valve handbooks: AEI, GEC, STC, RCA, about 20 books. I dug and found some data on a similar tetrode, possibly a newer version of 4B/55. I have 4B/550E, 4B/551B, 4B/551BD. It is in Volume 2B, Components, of S.T.C. Please find the scan in www.spinelectronics.eu/ftp/STC_tetrodes.pdf Petr, do they look similar? 73 - Marco IK1ODO