Return-Path: Received: from rly-df08.mx.aol.com (rly-df08.mail.aol.com [172.19.156.21]) by air-df04.mail.aol.com (v123.4) with ESMTP id MAILINDF043-56f49ca7275248; Wed, 25 Mar 2009 14:05:58 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-df08.mx.aol.com (v123.4) with ESMTP id MAILRELAYINDF086-56f49ca7275248; Wed, 25 Mar 2009 14:05:43 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1LmXTX-0001PE-LT for rs_out_1@blacksheep.org; Wed, 25 Mar 2009 18:05:15 +0000 Received: from [83.244.159.144] (helo=relay3.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1LmXTX-0001P5-7s for rsgb_lf_group@blacksheep.org; Wed, 25 Mar 2009 18:05:15 +0000 Received: from smtp27.orange.fr ([80.12.242.96]) by relay3.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1LmXTT-00026I-2P for rsgb_lf_group@blacksheep.org; Wed, 25 Mar 2009 18:05:15 +0000 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf2721.orange.fr (SMTP Server) with ESMTP id 6BDE11C000A0 for ; Wed, 25 Mar 2009 19:05:01 +0100 (CET) Received: from JR (Mix-Dijon-106-3-228.w193-248.abo.wanadoo.fr [193.248.130.228]) by mwinf2721.orange.fr (SMTP Server) with ESMTP id 7A0431C00085 for ; Wed, 25 Mar 2009 19:05:00 +0100 (CET) X-ME-UUID: 20090325180500499.7A0431C00085@mwinf2721.orange.fr Message-ID: <200903251904390893.465D158C@smtp.wanadoo.fr> In-Reply-To: <008c01c9ad63$4e9a9190$6401a8c0@asus> References: <86B4F549F8F247DDA470143B3BE77364@Hugh> <008c01c9ad63$4e9a9190$6401a8c0@asus> X-Mailer: Courier 3.50.00.09.1098 (http://www.rosecitysoftware.com) (P) Date: Wed, 25 Mar 2009 19:04:39 +0100 From: "John RABSON" To: rsgb_lf_group@blacksheep.org Mime-Version: 1.0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: RE: Re: TDA2003, TDA2030 for PA? Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable 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-IP: 193.82.116.20 TDA2003 used for Heyphone on 87kHz. 73 John *********** REPLY SEPARATOR *********** On 25/03/2009 at 16:03 Gary - G4WGT wrote: >Hi Petr, > >I have tested a TDA2030 for a 500KHz driver & is OK for 136KHz as other >authors have stated. > >It does fall off very rapidly from 200KHz & higher & is of no use at >500KHz. > >73 > >Gary - G4WGT. > > > >-----Original Message----- >From: owner-rsgb_lf_group@blacksheep.org >[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Hugh_m0wye >Sent: 25 March 2009 15:01 >To: rsgb_lf_group@blacksheep.org >Subject: LF: Re: TDA2003, TDA2030 for PA? > >I successfully made a TDA2030 amplifier which i used for all my intial=20 >experimenting on 137kHz >Photo http://www.m0wye.radiouk.com/lfamp.jpg >The data sheet for this IC claims a bandwidth of 140kHz so it won't work >on=20 >500kHz. >I think I got about 6Watts out. Not all the audio ICs have as much >bandwidth > >as this. >You need a matching circuit on the output to convert the low impedance of=20 >the amp to 50 ohms - or whatever your antenna system uses. >73 >Hugh M0WYE > > > > >----- Original Message -----=20 >From: "Petr Mal=FD" >To: >Sent: Wednesday, March 25, 2009 1:38 PM >Subject: LF: TDA2003, TDA2030 for PA? > > >Hi all, > >My intention is to build a small transmitter up to some 10W for 136 and >505=20 >kHz, this time not the D class, but B or AB class. >I think of employing AF amplifiers such as TDA2003, TDA2030, or similar. >Of=20 >course, mainly 505 kHz is rather out of range so that nothing is >guaranteed. > >This is why I ask before experimenting. >Did anybody try to use these for 136/505 kHz? > >Tks, 73, Petr, OK!FIG >http://ok1fig.nagano.cz