Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dl03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 5E2673800012B; Wed, 15 Feb 2012 16:41:27 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1RxmaU-0005BC-RH for rs_out_1@blacksheep.org; Wed, 15 Feb 2012 21:40:30 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1RxmaU-0005B3-F9 for rsgb_lf_group@blacksheep.org; Wed, 15 Feb 2012 21:40:30 +0000 Received: from mailout-de.gmx.net ([213.165.64.22]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1RxmaR-0006OE-Sf for rsgb_lf_group@blacksheep.org; Wed, 15 Feb 2012 21:40:30 +0000 Received: (qmail invoked by alias); 15 Feb 2012 21:40:21 -0000 Received: from p4FD0A03D.dip.t-dialin.net (EHLO Clemens04) [79.208.160.61] by mail.gmx.net (mp032) with SMTP; 15 Feb 2012 22:40:21 +0100 X-Authenticated: #17214767 X-Provags-ID: V01U2FsdGVkX19W3DBqqOJWCPHLrHG1V45Q6RzfxuQfQj4jYd/Q5B n3JZuKl75tHvlF Message-ID: <002801ccec2a$6b148430$1502a8c0@Clemens04> From: "Clemens Paul" To: References: <6C05E5021A484E229E4D20124C3D4AA9@TraceyPC> <002d01cceb30$87c42cc0$0401a8c0@xphd97xgq27nyf>,<4F3A8898.40302@xs4all.nl> <7E7DFBB4D102A04DB5ADC88D66628A4A015771@ICTS-S-MBX5.luna.kuleuven.be> Date: Wed, 15 Feb 2012 22:40:17 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3664 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3664 X-Y-GMX-Trusted: 0 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: WRC-12 Approves the New 472-479 kHz Amateur Radio Allocation Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:414785696:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d4ad14f3c26861e15 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none Greetings all, I wonder what "secondary user on non-interference basis" means in practice. As we know most NDBs are AM modulated with about 1kHz. Now it would be interesting to know what selectivity/bandwidth DF receivers for NDBs in aeroplanes might have. Imagine they have 1kHz or even 2kHz (quite possible). For non interfering such a receiver one would have to stay well without that BW. Hence with a few NDBs spread between 422 and 479kHz there would virtually remain no usable frequency for us amateurs if we wanted to make 100% sure not to interfere any aeroplanes' beacon reception. 73 Clemens DL4RAJ