Return-Path: Received: from mtain-md03.r1000.mx.aol.com (mtain-md03.r1000.mx.aol.com [172.29.96.87]) by air-dc05.mail.aol.com (v129.4) with ESMTP id MAILINDC051-86014c03ebf7357; Mon, 31 May 2010 13:03:51 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-md03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 33C2538000397; Mon, 31 May 2010 13:03:50 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OJ8Nv-0003Cc-Pd for rs_out_1@blacksheep.org; Mon, 31 May 2010 18:02:43 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OJ8Nv-0003CT-Dm for rsgb_lf_group@blacksheep.org; Mon, 31 May 2010 18:02:43 +0100 Received: from moutng.kundenserver.de ([212.227.126.187]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OJ8Nt-0003Ig-1i for rsgb_lf_group@blacksheep.org; Mon, 31 May 2010 18:02:43 +0100 Received: from [192.168.1.64] (188-221-89-85.zone12.bethere.co.uk [188.221.89.85]) by mrelayeu.kundenserver.de (node=mrbap1) with ESMTP (Nemesis) id 0LpPi1-1OxRHj0E5d-00epS6; Mon, 31 May 2010 19:02:34 +0200 From: "Dave Sergeant" To: rsgb_lf_group@blacksheep.org Date: Mon, 31 May 2010 18:02:33 +0100 MIME-Version: 1.0 Message-ID: <4C03EBA9.10216.27C4139@dave.davesergeant.com> In-reply-to: References: <20100530.082855.1608.1.riese-k3djc@juno.com>, <4C03CF6B.5040909@gmx.com>, X-mailer: Pegasus Mail for Windows (4.52) Content-description: Mail message body X-Provags-ID: V01U2FsdGVkX19YWnB6uWH/oIxQrjsXZvBaTF4xcaD6Ef8AGLU scpbIFCiLmRUs/0WU+1YzIMvC+M7YhRDc+N2w7vyOqANoaPjrd ZgoddF/DKbT3/EvFcYx4u82e998kBt6 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: LF: Re: 8.97kc - TV transformer info needed Content-type: text/plain; charset=US-ASCII 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=0.0 required=5.0 tests=none 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: 3039ac1d60574c03ebf615d6 X-AOL-IP: 193.82.116.20 On 31 May 2010 at 18:22, Rik Strobbe wrote: > Hello Mike, > > just one thing to keep in mind: a transformer with a voltage ratio of > about 430 (300/0.7) will also act as a 1 to 185000 impedance > transformer. As a result the slightest resistive load at the HV side > (eg. a 1 Meg Ohm resistor across the HV side) will probably do collapse > the output voltage. > > 73, Rik ON7YD > Yes, I am getting more and more confused about how you are using these transformers and what you are trying to do with them. If you are talking about transformers with a tapped primary (designed for interfacing with a transistor line output stage) and a seperate EHT winding which has a direct output to drive a tripler multiplier/rectifier at around 7kV (to produce 25kV EHT) then that secondary winding will be designed for a maximum EHT current of a few mA, maybe under 1mA depending on the CRT design. How are you going to match that into a 50 ohm load?... 73 Dave G3YMC http://www.davesergeant.com