Return-Path: <majordom@post.thorcom.com> Received: (qmail 18668 invoked from network); 21 Mar 2001 12:37:31 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 21 Mar 2001 12:37:31 -0000 Received: (qmail 16174 invoked from network); 21 Mar 2001 12:37:30 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 21 Mar 2001 12:37:30 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14fhmQ-0002hC-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 21 Mar 2001 12:31:58 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from [213.2.16.106] (helo=rsgb.org.uk) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14fhmO-0002h5-00 for rsgb_lf_group@blacksheep.org; Wed, 21 Mar 2001 12:31:57 +0000 Received: from miked by rsgb.org.uk with SMTP (MDaemon.v2.8.7.5.R) for <rsgb_lf_group@blacksheep.org>; Wed, 21 Mar 2001 12:30:34 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 From: "Mike Dennison" <mike.dennison@rsgb.org.uk> To: rsgb_lf_group@blacksheep.org Date: Wed, 21 Mar 2001 12:30:32 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 8bit Subject: LF: WOLF - Transmit? Message-ID: <3AB89EE8.130.AB12B1@localhost> X-Mailer: Pegasus Mail for Win32 (v3.12c) X-MDaemon-Deliver-To: rsgb_lf_group@blacksheep.org X-Return-Path: miked@mail Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: <majordom@post.thorcom.com> Ok, so having cracked the receive side, how do I transmit WOLF? As I understand it there are three methods: 1 - Audio from the soundcard is fed into a 136kHz SSB transmitter, including of course an HF SSB Tx with a transverter. Presumably the transmission is independent of which sideband is selected. 2 - Audio from the soundcard can be combined with the 'VFO' in an XOR gate and fed into an amplifier - presumably linear. This looks useful to me as I have a 200W linear amp. 3 - The M0BMU method that allows the use of a non-linear Class D Tx. How and why does this work? All three methods are potentially simple, but are made complex by the need for very careful bandwidth tailoring to keep the transmission to about 20Hz wide. Have I got any of this wrong? Is there anything published on the subject? What is in use? I understand that some Lowfers have used WOLF, but I suspect that bandwidth has not been an issue because of the total width of the allocation and the low ERP. I believe that Larry, VA3LK, has transmitted WOLF, but again perhaps the bandwidth was not a problem. Jim, will you publish your circuits? Or perhaps they are rig specific? It appears relatively easy to get going on receive but practical transmit has an information black hole. Advice, please. Mike, G3XDV (IO91VT) http://www.lf.thersgb.net