Return-Path: Received: (qmail 57496 invoked from network); 23 Nov 2004 13:48:43 -0000 Received: from unknown (HELO ptb-spamcore01.plus.net) (192.168.71.1) by ptb-mailstore02.plus.net with SMTP; 23 Nov 2004 13:48:43 -0000 Received: from mailnull by ptb-spamcore01.plus.net with spamcore-l-b (Exim 4.32; FreeBSD) id 1CWbKD-00095F-SR for dave@picks.force9.co.uk; Tue, 23 Nov 2004 14:07:22 +0000 Received: from [192.168.67.1] (helo=ptb-mxcore01.plus.net) by ptb-spamcore01.plus.net with esmtp (Exim 4.32; FreeBSD) id 1CWbKD-00095B-L3 for dave@picks.force9.co.uk; Tue, 23 Nov 2004 14:07:21 +0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore01.plus.net with esmtp (Exim 4.30; FreeBSD) id 1CWb2A-0006mH-QW for dave@picks.force9.co.uk; Tue, 23 Nov 2004 13:48:42 +0000 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1CWb1V-0008Q1-V3 for rs_out_1@blacksheep.org; Tue, 23 Nov 2004 13:48:01 +0000 Received: from [193.82.116.30] (helo=relay.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1CWb1V-0008Ps-K4 for rsgb_lf_group@blacksheep.org; Tue, 23 Nov 2004 13:48:01 +0000 Received: from mail.nrtco.net ([216.168.96.52]) by relay.thorcom.net with esmtp (Exim 4.41) id 1CWb1L-0008Sf-Lg for rsgb_lf_group@blacksheep.org; Tue, 23 Nov 2004 13:48:01 +0000 Received: from nocturna-y1zrar (nrtcorback-216-168-120-89.nrtco.net [216.168.120.89]) by mail.nrtco.net (8.12.10/8.12.1) with SMTP id iANDpVHC026264 for ; Tue, 23 Nov 2004 08:51:31 -0500 Message-Id: <3.0.6.32.20041123084747.00c3d4f0@magma.ca> X-Sender: ve2iq@magma.ca X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Tue, 23 Nov 2004 08:47:47 -0500 To: rsgb_lf_group@blacksheep.org From: Bill de Carle In-Reply-To: <01C4D15E.C5205CE0.actalbot@southsurf.com> Mime-Version: 1.0 X-SPF-Result: relay.thorcom.net: 216.168.96.52 is neither permitted nor denied by domain of magma.ca X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=no, Subject: Re: LF: Linear amplifiers , MSK, and 500kHz Content-Type: text/plain; charset=us-ascii; format=flowed X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com 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-Spam-Filtered: by PlusNet SpamCORE (v3.00) Content-transfer-encoding: 8bit At 01:17 PM 11/23/2004 -0000, you wrote: >Has anyone got anywhere with developing soundcard based MSK ? Surely that is >the next obvious move on LF where switch mode PAs rule and a linear PA isn't a >realistic option for high powers, knocking PSK31 on the head. I gave up on it. Most of all, I found it very difficult to code efficiently. It's quite sensitive to small frequency errors, and I recall running some tests which satisfied me the MSK error rate was actually *worse* than the BPSK we were using. The emphasis here is trying to copy things I couldn't copy before, not on conserving bandwidth. Yes, MSK is a great bandwidth-saver, but the 160-190 Khz North American unlicensed band is not used too much and we don't yet have an amateur allocation. Maybe if we ever get 137 Khz I'll take it up again. It may be easier to implement with GPS-disciplined timing and frequency control. If I can make some time I'll look into it from that perspective. Bill