Return-Path: X-Spam-DCC: paranoid 1002; 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=-0.7 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE,RATWARE_GECKO_BUILD autolearn=no 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 t9HG0309021442 for ; Sat, 17 Oct 2015 18:00:03 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ZnTrX-0001cC-LU for rs_out_1@blacksheep.org; Sat, 17 Oct 2015 16:57:39 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ZnTrX-0001bw-BR for rsgb_lf_group@blacksheep.org; Sat, 17 Oct 2015 16:57:39 +0100 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.86) (envelope-from ) id 1ZnTqT-0001H8-DC for rsgb_lf_group@blacksheep.org; Sat, 17 Oct 2015 16:57:38 +0100 Received: from dovecot03.posteo.de (dovecot03.posteo.de [172.16.0.13]) by mout01.posteo.de (Postfix) with ESMTPS id C9C2A2094B for ; Sat, 17 Oct 2015 17:56:20 +0200 (CEST) Received: from mail.posteo.de (localhost [127.0.0.1]) by dovecot03.posteo.de (Postfix) with ESMTPSA id 3ndTVD5G4qz5vN8 for ; Sat, 17 Oct 2015 17:56:20 +0200 (CEST) Message-ID: <56226FA4.9050403@posteo.de> Date: Sat, 17 Oct 2015 17:56:20 +0200 From: DK7FC User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <08B5A81DD2D14C84874DD10EEB145569@lindavideo> In-Reply-To: <08B5A81DD2D14C84874DD10EEB145569@lindavideo> X-Scan-Signature: e2fb1a5df1e2bc3146a6f486b4640b03 Subject: Re: LF: TX Toroid Material Content-Type: multipart/alternative; boundary="------------030802000708080703060103" 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: 4433 This is a multi-part message in MIME format. --------------030802000708080703060103 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hi Ken, I would first transform to 50 Ohm using a BIG ferrite core and then use iron powder cores to build the LPF. T-200-2 types work fine on MF for decent power levels :-) 73, Stefan Am 17.10.2015 17:41, schrieb Ken: > > Dear All. I am having problems with the choice of material for the > output network of the 475kHz Valve TX. The network is an L -- C -- L, > 'T' network with an input impedance of 2100 ohms and a load of 50 > ohms, for this configuration the input L is 7.7mH, shunt capacitance > is 117pf, and output L is 1.1mH. The PA design using a 6146 low power > or 813 high power work fine when simulated using LT spice IV. When > testing in the real world using the 6146 there is in excess of 800v > rms rf on the network side of the anode coupling capacitor, but > nothing after the input L. I can only conclude that I using the wrong > type material for the toroids, I used the largest size (unmarked) > toroid which gave me a modest number of turns. I have checked the > Amidon tables and Iron Powder because of the low A_L values, which > leaves Ferrite, which mix would you recommend? The simulations give me > output powers 90W for the 6146, and 300W for the 813. I would be > grateful for any core material advice . > > Ken Wright. > > M0KHW > --------------030802000708080703060103 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi Ken,

I would first transform to 50 Ohm using a BIG ferrite core and then use iron powder cores to build the LPF. T-200-2 types work fine on MF for decent power levels :-)

73, Stefan

Am 17.10.2015 17:41, schrieb Ken:

Dear All. I am having problems with the choice of material for the output network of the 475kHz Valve TX. The network is an L – C – L, ‘T’ network with an input impedance of 2100 ohms and a load of 50 ohms, for this configuration the input L is 7.7mH, shunt capacitance is 117pf, and output L is 1.1mH. The PA design using a 6146 low power or 813 high power work fine when simulated using LT spice IV. When testing in the real world using the 6146 there is in excess of 800v rms rf on the network side of the anode coupling capacitor, but nothing after the input L. I can only conclude that I using the wrong type material for the toroids, I used the largest size (unmarked) toroid which gave me a modest number of turns. I have checked the Amidon tables and Iron Powder because of the low A_L values, which leaves Ferrite, which mix would you recommend? The simulations give me output powers 90W for the 6146, and 300W for the 813. I would be grateful for any core material advice .

Ken Wright.

M0KHW

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