Return-Path: Received: (qmail 4483 invoked from network); 15 Aug 2003 19:50:20 -0000 Received: from murphys.services.quay.plus.net (212.159.14.225) by netmail00.services.quay.plus.net with SMTP; 15 Aug 2003 19:50:20 -0000 Received: (qmail 8781 invoked from network); 15 Aug 2003 19:50:07 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from post.thorcom.com (193.82.116.70) by murphys.services.quay.plus.net with SMTP; 15 Aug 2003 19:50:07 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.14) id 19nkZa-0007Bg-Tq for rsgb_lf_group-outgoing@blacksheep.org; Fri, 15 Aug 2003 20:49:18 +0100 Received: from [194.25.134.82] (helo=mailout05.sul.t-online.com) by post.thorcom.com with esmtp (Exim 4.14) id 19nkZX-0007BX-4K for rsgb_lf_group@blacksheep.org; Fri, 15 Aug 2003 20:49:15 +0100 Received: from fwd04.aul.t-online.de by mailout05.sul.t-online.com with smtp id 19nkZW-0004g5-00; Fri, 15 Aug 2003 21:49:14 +0200 Received: from (TbyCX0ZF8e+Owx2sNvD379Cz3iy0AEc-39x9FuSpqRZPDUI7N8afYZ@[62.155.252.220]) by fwd04.sul.t-online.com with smtp id 19nkZQ-0IJ7tA0; Fri, 15 Aug 2003 21:49:08 +0200 From: "jannsen" <0482183881-0001@t-online.de> To: rsgb_lf_group@blacksheep.org References: <5.1.0.14.0.20030815154505.00b0a898@gemini.herts.ac.uk> X-Mailer: T-Online eMail 2.34 MIME-Version: 1.0 Date: Fri, 15 Aug 2003 21:49:08 +0200 Message-ID: <19nkZQ-0IJ7tA0@fwd04.sul.t-online.com> X-Seen: false X-ID: TbyCX0ZF8e+Owx2sNvD379Cz3iy0AEc-39x9FuSpqRZPDUI7N8afYZ Subject: Re: LF: Variegated witterings. Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-0.8 required=5.0tests=FROM_ENDS_IN_NUMS,QUOTED_EMAIL_TEXT,REFERENCES, USER_AGENT_TONLINEversion=2.55 X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp) X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rsgb_lf_group-outgoing@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false James Moritz schrieb: .............. ............ > My cure was to add a low-pass > filter between the matching transformer at the amp output and the coax > feeder - the usual pi-section designs won't help due to the shunt > capacitors at their input, so I used a tee configuration instead with a > series inductor at the filter input. The low-pass filter effectively > isolates the amplifier from the ipedance variations at the load. After > this, I had no trouble. I have occasionally also had problems with class D > amps and peculiar loads - these were also solved using a low-pass filter at > the TX output. > > Cheers, Jim Moritz > 73 de M0BMU > > Hi Jim, wld you pse give a detailed specification of your tee configuration with the series inductor at the filter input ? tks in advance. regards Uwe/dj8wx