Return-Path: Received: (qmail 39999 invoked from network); 26 Jan 2004 20:46:35 -0000 Received: from unknown (HELO ptb-mxscan03.plus.net) (212.159.14.237) by ptb-mailstore01.plus.net with SMTP; 26 Jan 2004 20:46:35 -0000 Received: (qmail 39227 invoked from network); 26 Jan 2004 20:46:35 -0000 X-Filtered-by: Plusnet (hmail v1.01) X-Spam-detection-level: 11 Received: from ptb-mxcore03.plus.net (212.159.14.217) by ptb-mxscan03.plus.net with SMTP; 26 Jan 2004 20:46:34 -0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore03.plus.net with esmtp (Exim) id 1AlDcs-0009Jr-H3 for dave@picks.force9.co.uk; Mon, 26 Jan 2004 20:46:30 +0000 X-Fake-Domain: majordom Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1AlDav-0007Uz-OX for rs_out@blacksheep.org; Mon, 26 Jan 2004 20:44:29 +0000 Received: from [62.58.50.88] (helo=postbode01.zonnet.nl) by post.thorcom.com with esmtp (Exim 4.14) id 1AlDau-0007Uj-S3 for rsgb_lf_group@blacksheep.org; Mon, 26 Jan 2004 20:44:28 +0000 Received: (qmail 17047 invoked by uid 10); 26 Jan 2004 20:43:57 -0000 Received: (vexira-qq 16913-87ADE4BF invoked from network) 26 Jan 2004 21:43:54 +0100 X-Fake-Domain: unknown Received: from unknown (HELO ibm) ([62.59.190.56]) (envelope-sender ) by postbode01.zonnet.nl (qmail-ldap-1.03) with SMTP for < >; 26 Jan 2004 20:43:54 -0000 X-Bad-Message-ID: no DNS (ibm) Message-ID: <000401c3e44c$16e59d20$2102000a@ibm> From: "Dick" To: rsgb_lf_group@blacksheep.org References: <005401c3e2ad$3d2d3ba0$6507a8c0@Main> <000801c3e38f$bbec4d40$1f00a8c0@dellboy> Date: Mon, 26 Jan 2004 21:35:21 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Antivirus: checked by Vexira MailArmor (version: 2.0.1.16; VAE: 6.23.0.2; VDF: 6.23.0.29; host: postbode01.zonnet.nl) Subject: LF: my 137kHz project...a little more signal now........ Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.60 (1.212-2003-09-23-exp) on post.thorcom.com X-Spam-Status: No, hits=0.9 required=5.0 tests=FROM_ENDS_IN_NUMS autolearn=no version=2.60 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: rs_out@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-PN-SPAMFiltered: yes X-Spam-Rating: 2 Well, I managed to get a nice 12Vtt square wave on 137kHz + all harmonics, and used this to drive a single IRF530, just to see what happens. Had to use a resistor to crank down the current, as my powersupply couldn't handle it............ At least some interesting things happend......the filter coil get's warm..... well, I am not surprised as it is an T106-26 coil from a computer power supply. Also the 3mH coil in the DC-input line makes some nice noises........ All at 7V drainvoltage, and 1 Amp draincurrent. Measured 30Vtt sinus over an 47Ohm resistor, and around +30dBm, or 1 Watt over this same resistor. Far from ideal, I know, but just want to get some experience and do some tests starting with this very simple inefficient circuit. I am sure I'll get more power in the future when using other types of amplifiers. I think the 12V squarewave unit can drive a lot of other stuff, like multiple FET's via transformers etc. Now first need to build an bigger powersupply, a dummyload, and of course al the coilstuff for the antenna............ A 100V/10A power supply will be the next to go for......... Transformer is already there............... Dick, pa4vhf