Return-Path: Received: (qmail 216 invoked from network); 5 Dec 2000 13:30:15 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 5 Dec 2000 13:30:15 -0000 Received: (qmail 1769 invoked from network); 5 Dec 2000 13:25:19 -0000 Content-Transfer-Encoding: 8bit Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 5 Dec 2000 13:25:19 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 143Hyt-0007FL-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 05 Dec 2000 13:18:03 +0000 Received: from ns1.swh.sk ([192.108.125.33]) by post.thorcom.com with esmtp (Exim 3.16 #1) id 143Hyq-0007FG-00 for rsgb_lf_group@blacksheep.org; Tue, 05 Dec 2000 13:18:01 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from hermes.swh.sk (hermes [139.24.136.129]) by ns1.swh.sk (8.9.1/8.9.1) with ESMTP id OAA20934 for ; Tue, 5 Dec 2000 14:17:48 +0100 Received: from btss101a.swh.sk (btss.swh.sk [139.24.136.15]) by hermes.swh.sk (8.9.3/8.9.2) with ESMTP id OAA00145 for ; Tue, 5 Dec 2000 14:17:44 +0100 (MET) Received: by btss.swh.sk with Internet Mail Service (5.5.2448.0) id ; Tue, 5 Dec 2000 14:17:42 +0100 Message-ID: <29BDD4F529FCD311B631009027357C4E01AD87FC@btss103a.swh.sk> From: "Gasparik Richard" To: rsgb_lf_group@blacksheep.org Subject: RE: LF: Looking for 2-3 Watt Linear PA for LF Date: Tue, 5 Dec 2000 14:17:41 +0100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2448.0) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Hi Brian.. How did you drive two MRF linear amplifiers in parallel ? Rich OM2TW > -----Original Message----- > From: Brian Rogerson [SMTP:brian@esoterica.pt] > Sent: 5. december 2000 13:52 > To: rsgb_lf_group@blacksheep.org > Subject: Re: LF: Looking for 2-3 Watt Linear PA for LF > > Geri, > > >Does anyone of you have a proven scheme of a small linear PA available, > >that delivers about 2 or 3 Watts from 10 mW, preferably from 18 Volts > >(which is the voltage used by the exciter)? I am sure a small audio > >amplifier would do ... > > I have spent months fighting the TDA2030 which is only marginally stable. > > About three weeks ago I tried a LM1875, which has better bandwidth and > can be used down to a closed loop gain of 10dB. I am now using three > (one preamp and two in a bridge circuit) to drive two of David MRF > amplifiers in parallel. This IC is specified for +/- 24v but seems to > work quite happily on +/- 12v. > > 73, Brian > 73 Brian CT1DRP IN51QD 41 09 58N 08 39 11W > http://homepage.esoterica.pt/~brian >