Return-Path: Received: (qmail 22614 invoked from network); 21 Mar 2001 11:34:24 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 21 Mar 2001 11:34:24 -0000 Received: (qmail 12985 invoked from network); 21 Mar 2001 11:34:24 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 21 Mar 2001 11:34:24 -0000 Content-Transfer-Encoding: 8bit Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14fglp-0002EN-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 21 Mar 2001 11:27:17 +0000 Received: from bob.dera.gov.uk ([192.5.29.90]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14fglo-0002EI-00 for rsgb_lf_group@blacksheep.org; Wed, 21 Mar 2001 11:27:16 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id LAA24617; Wed, 21 Mar 2001 11:29:40 GMT Received: (qmail 14734 invoked from network); 21 Mar 2001 12:18:10 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from gauntlet.mail.dera.gov.uk (172.16.9.10) by baton.dera.gov.uk with SMTP; 21 Mar 2001 12:18:10 -0000 Received: by gauntlet.mail.dera.gov.uk; id MAA00328; Wed, 21 Mar 2001 12:04:54 GMT Received: from unknown(10.71.64.31) by gauntlet.mail.dera.gov.uk via smap (3.2) id xma000208; Wed, 21 Mar 01 12:04:24 GMT Received: from frn-gold-1.dera.gov.uk (unverified) by mailguard.dera.gov.uk (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Wed, 21 Mar 2001 11:32:01 +0000 Received: by frn-gold-1.dera.gov.uk with Internet Mail Service (5.0.1460.8) id ; Wed, 21 Mar 2001 11:26:21 -0000 Message-ID: <65AECDF1F89AD411900400508BFC869F9C03EC@pdw-mail-1.dera.gov.uk> From: "Talbot Andrew" To: rsgb_lf_group@blacksheep.org Subject: LF: RE: exact audio reference Date: Wed, 21 Mar 2001 11:26:22 -0000 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.0.1460.8) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Another solution is to run G3PLX's PSK31 SB software. There is a setup routine in the software that allows the Soundcard sampling rate to be calibrated. The procedure is given in the Help file, accessible from the menu bar. Again, an accurate audio frequency source will be necessary. The vectorscope in that software allows fine tuning accuracy to an arbitrary audio tone, and frequency resolution of less than 1Hz is clearly seen. So it becomes a useful tool for measuring carrier frequencies even if you don't actually want to use the PSK31 data mode. Andy G4JNT > > For those who want to calibrate the soundcard there is also a simple > hardware solution : > Take a CMOS4060 (14-stage divider with internal oscillator) > and let it run > with a xtal in the 8-12MHz range. At the end of the divider > chain (pin 3) > -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.