Return-Path: Received: (qmail 8132 invoked from network); 20 Mar 2001 15:19:00 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by 10.226.25.101 with SMTP; 20 Mar 2001 15:19:00 -0000 Received: (qmail 7017 invoked from network); 20 Mar 2001 15:19:01 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 20 Mar 2001 15:19:01 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14fNoI-0002oo-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 20 Mar 2001 15:12:34 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from d12lmsgate-2.de.ibm.com ([195.212.91.200]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14fNoG-0002ob-00 for rsgb_lf_group@blacksheep.org; Tue, 20 Mar 2001 15:12:33 +0000 Received: from d12relay02.de.ibm.com (d12relay02.de.ibm.com [9.165.215.23]) by d12lmsgate-2.de.ibm.com (1.0.0) with ESMTP id QAA45658 for ; Tue, 20 Mar 2001 16:11:23 +0100 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from usa.net (dyn9-87-105-37.italy.ibm.com [9.87.105.37]) by d12relay02.de.ibm.com (8.8.8m3/NCO v4.95) with ESMTP id QAA64464 for ; Tue, 20 Mar 2001 16:09:02 +0100 Message-ID: <3AB77304.B462970E@usa.net> Date: Tue, 20 Mar 2001 16:11:00 +0100 From: "Alberto di Bene" X-Mailer: Mozilla 4.73 [en] (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org Subject: LF: Re: WOLF - am I missing something ? References: <65AECDF1F89AD411900400508BFC869F9C03E6@pdw-mail-1.dera.gov.uk> 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: > Then I abandonned software > timing by using an external interface (a PIC) on the serial port and > ended up with something very similar to the VE2IQ I/F. > A few days ago I was thinking on how to generate a programmable frequency for an MFSK scheme (I did post a message on this reflector), and the DDS was one the possibilities. Thinking again at it, after all we just need the high order bit of the phase accumulator, as the TX is driven with a square wave. This makes the DAC completely unnecessary. Would it be possible then to implement a 32-bit phase accumulator with a PIC, to generate a frequency on the 137 kHz band ? My knowledge of PICs is quite limited, any PIC guru with an answer ? If positive, then it would be possible to make a really inexpensive outboard generator for such an MFSK modulation scheme. 73 Alberto I2PHD