Return-Path: Received: (qmail 15143 invoked from network); 17 Dec 2001 21:10:31 -0000 Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 17 Dec 2001 21:10:31 -0000 Received: (qmail 2995 invoked from network); 17 Dec 2001 21:10:40 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys.services.quay.plus.net with SMTP; 17 Dec 2001 21:10:40 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16G4zj-0007YU-00 for rsgb_lf_group-outgoing@blacksheep.org; Mon, 17 Dec 2001 21:08:19 +0000 Received: from mailman.zeta.org.au ([203.26.10.16]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16G4zh-0007YP-00 for rsgb_lf_group@blacksheep.org; Mon, 17 Dec 2001 21:08:18 +0000 Received: from steve (ppp224.dyn154.pacific.net.au [210.23.154.224]) by mailman.zeta.org.au (8.9.3/8.8.7) with SMTP id IAA21451 for ; Tue, 18 Dec 2001 08:07:29 +1100 Message-ID: <007101c1873f$8cf461c0$e09a17d2@steve> From: "Steve Olney" To: rsgb_lf_group@blacksheep.org References: <003301c186e8$dabdefe0$9fa1883e@g3aqc> <5.1.0.14.0.20011217162715.00abb350@gemini.herts.ac.uk> Subject: Re: LF: long haul QSO's Date: Tue, 18 Dec 2001 08:12:05 +1100 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2314.1300 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: G'day Stewart, Your 7-tone suggestion is appealing to me as it is a neat hybrid of AFK (Piccolo), FDK (Wanjina) and IFK modes that I have been playing with for a couple of years now. While it uses the IFK method of transmitting two sequential tones it also uses the frequency step direction to encode information (e. g. going from tone #1 to tone #2 encodes a different character than going from tone #2 to tone #1) which IFK does not. Neat. Also, although the information is contained in the frequency difference of two tones like FDK (although sequential), an absolute reference is required (like AFK). This is necessary to distinguish between, say sequential tone pairs #2 and #3 and sequential tones #3 and #4. If the stability of the transmission (and reception) is sufficient the system could be calibrated by a space character, but I think it would be difficult to do this by eye as stated, although easy for a machine decoded system. The frequency difference nature of the protocol allows that (calibrated by, say, recognising the seqential transmission of tones #1 and #7). Anyway, go for it. If it works, set a standard (I think spacing and timing are the only parameters which need to be established) so others can develop S/W and H/W to take it forward. Good work Stewart ! 73s Steve Olney (VK2ZTO/AXSO - QF56IK : Lat -33 34 07, Long +150 44 40) ============================================= HomePage URL: http://www.zeta.org.au/~ollaneg Containing:- ULF, ELF, VLF & LF Experimentation MF 22m Experimentation InfraSonic Experimentation Laser Comms DX =============================================