Return-Path: Received: (qmail 6198 invoked from network); 15 Jan 2002 21:12:38 -0000 Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 15 Jan 2002 21:12:38 -0000 Received: (qmail 28170 invoked from network); 15 Jan 2002 21:12:34 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 15 Jan 2002 21:12:34 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16QakH-0004ZO-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 15 Jan 2002 21:03:49 +0000 Received: from fep01.swip.net ([130.244.199.129] helo=fep01-svc.swip.net) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16QakG-0004ZJ-00 for rsgb_lf_group@blacksheep.org; Tue, 15 Jan 2002 21:03:49 +0000 Received: from oemcomputer ([212.151.9.189]) by fep01-svc.swip.net with SMTP id <20020115210300.HHOR1315.fep01-svc.swip.net@oemcomputer> for ; Tue, 15 Jan 2002 22:03:00 +0100 Message-ID: <002e01c19e08$13dc0d80$bd0997d4@oemcomputer> From: "Johan Bodin" To: rsgb_lf_group@blacksheep.org References: <7D653C9C42F5D411A27C00508BF8803DCB994D@pdw-mail-r1.dstl.gov.uk> Subject: LF: Re: An appeal to Windoze programmers Date: Tue, 15 Jan 2002 14:43:32 +0100 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 6.00.2600.0000 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: Yes, a Windoze vector scope would be a great tool/toy! Andy G4JNT wrote: > Some sort of calibration routine would be needed for use, either feeding in > a tone of exact known frequency and adjusting the NCO for a stationary > trace. The soundcard clocks can be quite unstable. Therefore I would suggest a second mode where both left and right inputs are used. The received signal is fed into one of the channels and a reference frequency is fed into the other. If the reference is a clean sine wave, a Hilbert transformer can be used to split it into the quadrature L.O. needed for the half-complex input mixer (real in - I/Q out). Another approach could be to keep the NCO and use a software PLL to lock the NCO "software clock" to the reference frequency. The reference doesn't have to be a pure sine wave in this case, I think. > One can play endlessly with such a tool ! I couldn't agree more! 73 Johan SM6LKM