Return-Path: Received: (qmail 14900 invoked from network); 6 Mar 2002 18:15:32 -0000 Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 6 Mar 2002 18:15:32 -0000 Received: (qmail 10731 invoked from network); 6 Mar 2002 18:15:29 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 6 Mar 2002 18:15:29 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16ihMs-0004ig-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 06 Mar 2002 19:46:30 +0000 Received: from rhenium.btinternet.com ([194.73.73.93]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16ihMr-0004ib-00 for rsgb_lf_group@blacksheep.org; Wed, 06 Mar 2002 19:46:29 +0000 Received: from host213-1-89-178.in-addr.btopenworld.com ([213.1.89.178] helo=default) by rhenium.btinternet.com with smtp (Exim 3.22 #8) id 16ifpz-0006Ki-00 for rsgb_lf_group@blacksheep.org; Wed, 06 Mar 2002 18:08:27 +0000 Message-ID: <000201c1c539$e92f8d60$b25901d5@default> From: "Alan Melia" To: "LF-Group" Subject: LF: New interference source? Date: Wed, 6 Mar 2002 15:49:38 -0000 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 4.72.3110.5 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: Hi all, I have a new 'sound' appearing on the band recently. It is quite distinct from the TV PSU noises. It seems to appear at the top end of the band for periods of time (I am not sure whether it goes off, or just drifts away) The main symptom is a growling (I am using LSB so this is the low audio frequencies) which is keyed for one second with 0.5 per second PRF. The spectrum on Argo is of a band of 50Hz sidebands which may be FSKed with a 0.5 Hz square wave, the shift must be in excess of 500Hz . I can't think of any domestic item that would be that precise "once every 2 secs" action.....the defrosting periods of a microwave oven are usually longer than that. (If it was that, then I have a neighbour who is defrosting either a Wooly Mamoth or a Dinosaur !!) Cheers de Alan G3NYK alan.melia@btinternet.com