Return-Path: Received: (qmail 17600 invoked from network); 28 Jan 2001 16:35:53 -0000 Received: from unknown (HELO murphys-inbound.servers.plus.net) (212.159.14.225) by excalibur.plus.net with SMTP; 28 Jan 2001 16:35:53 -0000 Received: (qmail 27645 invoked from network); 28 Jan 2001 16:30:00 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 28 Jan 2001 16:30:00 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 14Mubv-0000u4-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 28 Jan 2001 16:23:27 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from smtp-out1.bellatlantic.net ([199.45.40.143]) by post.thorcom.com with esmtp (Exim 3.16 #1) id 14Mubr-0000tz-00 for rsgb_lf_group@blacksheep.org; Sun, 28 Jan 2001 16:23:24 +0000 Received: from bellatlantic.net (client-151-200-117-45.bellatlantic.net [151.200.117.45]) by smtp-out1.bellatlantic.net (8.9.1/8.9.1) with ESMTP id LAA01665; Sun, 28 Jan 2001 11:23:09 -0500 (EST) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Message-ID: <3A7447C6.B890F46B@bellatlantic.net> Date: Sun, 28 Jan 2001 11:24:38 -0500 From: "Andre' Kesteloot" X-Mailer: Mozilla 4.7 [en]C-CCK-MCD NSCPCD47 (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org Cc: "lf-amrad" , "AMRAD Tacos" , "Timothy Hulick W9QQ" , "Stewart Nelson KK7KA" Subject: Re: LF: Proposed new LF signal format References: <23564246.980604804777.JavaMail.imail@chilly.excite.com> <001b01c08870$f6b97d80$d400a8c0@scgroup.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Stewart Nelson wrote: > [...] The WOLF signal is BPSK (at MS100), > [...] > Comments and suggestions welcome. > 73, > Stewart KK7KA Stewart is to be commended for developing the very interesting WOLF concept. One of the challenges we all face in LF work is the _reliable_ operation of high-power CW transmitters (I have a bunch of fried Power MosFets here in the shack that demonstrate that problem). Generating large amounts of RF power with a _linear_ amplifier is even more difficult, because of the problem one faces when one tries to bias several power MosFets in parallel. (I am assuming here that most radioamateurs will try to use cheap Mosfets, not expensive RF types). Ideally, for such applications as WOLF, one would need a linear amplifier, yet what cheap power MosFets seem to like best is on/off operation :-) One approach to that problem was offered by Timothy Hulick Ph.D. W9QQ, in two papers he presented at the AMRAD Technical Symposium that was held here in Virginia on 17 June 2000. These papers: "The Digital Amplitude Modulator" and "The Digital Linear Amplifier" were reprinted in the Symposium's proceedings. 73 Andre' N4ICK