Return-Path: Received: (qmail 14766 invoked from network); 16 Jun 1999 22:31:52 +0100 Received: from unknown (HELO magnus.force9.net) (195.166.128.27) by guiness.force9.net with SMTP; 16 Jun 1999 22:31:52 +0100 Received: (qmail 19532 invoked from network); 16 Jun 1999 19:50:37 -0000 Received: from unknown (HELO post.thorcom.com) (194.75.130.70) by magnus.plus.net.uk with SMTP; 16 Jun 1999 19:50:37 -0000 Received: from troy.blacksheep.org ([194.75.183.50] ident=root) by post.thorcom.com with esmtp (Exim 2.04 #3) id 10u0rt-000411-00; Tue, 15 Jun 1999 22:35:41 +0100 Received: (from root@localhost) by troy.blacksheep.org (8.6.12/8.6.12) id VAA18884 for rsgb_lf_group-outgoing; Tue, 15 Jun 1999 21:35:00 GMT Received: from post.thorcom.com (root@post.unica.co.uk [194.75.183.70]) by troy.blacksheep.org (8.6.12/8.6.12) with ESMTP id VAA18880 for ; Tue, 15 Jun 1999 21:34:57 GMT Received: from merlins.force9.net ([195.166.128.23]) by post.thorcom.com with smtp (Exim 2.04 #3) id 10u0qV-00040t-00 for rsgb_lf_group@blacksheep.org; Tue, 15 Jun 1999 22:34:15 +0100 Received: (qmail 32405 invoked from network); 15 Jun 1999 21:38:40 -0000 Received: from mayfly.plus.net.uk (HELO mayfly.force9.net) (195.166.128.28) by merlins.force9.net with SMTP; 15 Jun 1999 21:38:40 -0000 Received: (qmail 17576 invoked from network); 15 Jun 1999 21:09:38 -0000 Received: from 414.hiper01.shef.dialup.force9.net (HELO prstesv1) (195.166.143.158) by mayfly.plus.net.uk with SMTP; 15 Jun 1999 21:09:38 -0000 Message-ID: <001401beb772$e65c0e60$0600a8c0@prstesv1.prestel.co.uk> From: "Dave" To: rsgb_lf_group@blacksheep.org Subject: LF: Re: Frequency separation: Normal CW operation Date: Tue, 15 Jun 1999 22:03:58 +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 4.72.3110.1 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org Steve et al... I normally try to leave a 200Hz gap between my transmission and other strongish ones but it is sometimes difficult to find a spot on a Saturday or Sunday morning... It is certainly something that everyone must consider when operating on LF, unless you want to hear the whole band at once, use the tightest filter you can get! I recommend a TS850 with International Radio 400Hz filters at both IFs allowing full use of the IF bandwidth controls... superb. 73, dave G3YXM >Over the past month, I had become aware that a certain G-station - new >to LF, but with a very commanding signal on 136.53 kHz - was often heard >to 'clobber' QSOs, and CQ calls from other stations. This puzzled me >greatly, because I knew that the station concerned could usually hear >the other stations involved. > >It appeared to me - and to others - as if the station was deliberately >causing QRM to his fellow LFers. > >Having recently telephoned the operator concerned, I can report that the >reason for the unintentional QRM amounted to a lack of understanding >concerning typical IF bandwidths employed by amateurs on 136 kHz. The >operator concerned is using a receiver with an effective IF bandwidth of >50 Hz (!), and he was quite happy to operate to within 100Hz of other >stations! > >I advised the operator that we tend to assume a receive IF bandwidth of >250 Hz and generally aim to maintain a 300 Hz separation from other >stations. (I believe that 300 Hz has been the figure quoted during LF >Group discussions and at the LF Forum.) I hope I did the right thing. > >But with the fancy new receivers now available (which I'll probably >never be able to afford!), does the Group still feel 300 Hz to be a >reasonable separation for normal CW operation? > >Regards to all, >Steve GW4ALG > > >