Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id vA8DwGjc015491 for ; Wed, 8 Nov 2017 14:58:20 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eCQmf-0007RL-RZ for rs_out_1@blacksheep.org; Wed, 08 Nov 2017 13:52:49 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eCQmf-0007RC-90 for rsgb_lf_group@blacksheep.org; Wed, 08 Nov 2017 13:52:49 +0000 Received: from mout02.posteo.de ([185.67.36.66]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1eCQmc-0001LT-Lw for rsgb_lf_group@blacksheep.org; Wed, 08 Nov 2017 13:52:48 +0000 Received: from submission (posteo.de [89.146.220.130]) by mout02.posteo.de (Postfix) with ESMTPS id 1EC8D20CF5 for ; Wed, 8 Nov 2017 14:52:46 +0100 (CET) Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3yX7624zvZz10Jb for ; Wed, 8 Nov 2017 14:52:42 +0100 (CET) Message-ID: <5A030C22.70604@posteo.de> Date: Wed, 08 Nov 2017 14:52:34 +0100 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: <22d6c712-43af-3a5d-099e-adb285f086a1@n1bug.com> <7d1279b6d1a84b692d281d48901f2b23@xs4all.nl> <5A03089B.6060600@posteo.de> In-Reply-To: <5A03089B.6060600@posteo.de> X-Spam-Score: -0.0 (/) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Am 08.11.2017 14:37, schrieb DK7FC: > And i would add a 1000 uF electrolytic capacitor with a low internal > resistance (the good ones :-) ) near the Drain, in parallel to the 1 > uF capacitor. Sorry that was wrong. Actually there should be a small inductor between that large C and the drain, just a few uH, like others said before. That value is not so critical, it can be 10 uH or so. [...] Content analysis details: (-0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Scan-Signature: 59677119386dcf9f1872cb454dc1331d Subject: Re: LF: PA problem Content-Type: text/plain; charset=UTF-8; format=flowed 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 Am 08.11.2017 14:37, schrieb DK7FC: > And i would add a 1000 uF electrolytic capacitor with a low internal > resistance (the good ones :-) ) near the Drain, in parallel to the 1 > uF capacitor. Sorry that was wrong. Actually there should be a small inductor between that large C and the drain, just a few uH, like others said before. That value is not so critical, it can be 10 uH or so. 73, Stefan PS: In 2001 i built a 1 kW class E PA for 137 kHz using a single IRFP360 and 80V DC. I also built a 13.8 V version using a IRF540N giving 100 W. But it has always been a high effort to get a good efficiency. Since many years i prefer class D PAs.