Return-Path: Received: (qmail 72141 invoked from network); 5 Feb 2004 18:41:20 -0000 Received: from unknown (HELO ptb-mxscan02.plus.net) (212.159.14.236) by ptb-mailstore03.plus.net with SMTP; 5 Feb 2004 18:41:20 -0000 Received: (qmail 66641 invoked from network); 5 Feb 2004 18:41:20 -0000 X-Filtered-by: Plusnet (hmail v1.01) X-Spam-detection-level: 11 Received: from ptb-mxcore02.plus.net (212.159.14.216) by ptb-mxscan02.plus.net with SMTP; 5 Feb 2004 18:41:19 -0000 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore02.plus.net with esmtp (Exim) id 1AooRD-000HDA-8k for dave@picks.force9.co.uk; Thu, 05 Feb 2004 18:41:19 +0000 X-Fake-Domain: majordom Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1AooPj-0008R3-HH for rs_out@blacksheep.org; Thu, 05 Feb 2004 18:39:47 +0000 Received: from [213.40.2.14] (helo=gourd.sout.netline.net.uk) by post.thorcom.com with esmtp (Exim 4.14) id 1AooPi-0008Qt-Ea for rsgb_lf_group@blacksheep.org; Thu, 05 Feb 2004 18:39:46 +0000 Received: from [213.40.203.162] (helo=taylormade) by gourd.sout.netline.net.uk with smtp (Exim 4.24) id 1AooPD-0000pB-CC for rsgb_lf_group@blacksheep.org; Thu, 05 Feb 2004 18:39:15 +0000 From: "G4WGT - Gary" To: rsgb_lf_group@blacksheep.org Date: Thu, 5 Feb 2004 18:39:20 -0000 Message-ID: MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-reply-to: <001701c3eaa0$1e8670e0$6507a8c0@Main> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: RE: G0MRF 300w Tx & DDS VFO Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Checker-Version: SpamAssassin 2.60 (1.212-2003-09-23-exp) on post.thorcom.com X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.60 X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-PN-SPAMFiltered: yes X-Spam-Rating: 1 Hi Alan & LF, The frequency calibration of my DDS VFO is so good (with a little hit & miss twiddling)that it is zero beat with BBC Radio 4 on 198 Khz radio transmission & the freq stability is every bit as good, during hours of testing with 198 Khz as a reference I cannot detect any variation. The problem as I have specified in my e-mails is the low output. Last night I checked back to the DDS IC & there are no substantial losses in the signal path, even the insertion loss of the LPF is negligable. Here are the actual levels into 50 ohm load at the output of the DDS VFO. 137 & 274 Khz - 22mV 1.0 Mhz - 50mV 2.0 Mhz - 60mV 5.0 Mhz - 80mV 10.0 Mhz - 150mV 15.0 Mhz - 250mV 20.0 Mhz - 250mV 25.0 Mhz - 150mV 30.0 Mhz - 75mV 35.0 Mhz - 65mV 40.0 Mhz - 50mV I am also sending this info to the organiser of the offer/project from the G-QRP Club asking for his help, advice or a further contact point. By the way, the DDS chip is a Analog Devices AD9850 w/ 120 MHz Clock 73 Gary - G4WGT -----Original Message----- From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Alan Melia Sent: 03 February 2004 21:53 To: rsgb_lf_group@blacksheep.org Subject: LF: Re: RE: Re: Re: G0MRF 300w Tx & DDS VFO Yes Ok Gary, I guessed it was so. I just wondered whther you had a "tight" filter. The signal out of the chip (do be carefull here) should be a logic level ..i.e. 5v p-p I would have thought (??) Cheers de Alan G3NYK