Return-Path: Received: from rly-mg04.mx.aol.com (rly-mg04.mail.aol.com [172.20.83.110]) by air-mg10.mail.aol.com (v123.4) with ESMTP id MAILINMG102-a094a131d84ca; Tue, 19 May 2009 16:59:11 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-mg04.mx.aol.com (v123.4) with ESMTP id MAILRELAYINMG043-a094a131d84ca; Tue, 19 May 2009 16:58:46 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1M6WNb-0006R7-I9 for rs_out_1@blacksheep.org; Tue, 19 May 2009 21:57:43 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1M6WNb-0006Qy-5V for rsgb_lf_group@blacksheep.org; Tue, 19 May 2009 21:57:43 +0100 Received: from mk-filter-1-a-1.mail.uk.tiscali.com ([212.74.100.52]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1M6WNY-0004mq-Dt for rsgb_lf_group@blacksheep.org; Tue, 19 May 2009 21:57:42 +0100 X-Trace: 201794229/mk-filter-1.mail.uk.tiscali.com/B2C/$b2c-THROTTLED-DYNAMIC/b2c-CUSTOMER-DYNAMIC-IP/88.106.18.229/None/g4wgt@tiscali.co.uk X-SBRS: None X-RemoteIP: 88.106.18.229 X-IP-MAIL-FROM: g4wgt@tiscali.co.uk X-SMTP-AUTH: X-MUA: Microsoft Office Outlook 11Produced By Microsoft MimeOLE V6.00.2900.3350 X-IP-BHB: Once X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AnMFADm6EkpYahLl/2dsb2JhbACCJytWToZRhCPBMgeDewU X-IronPort-AV: E=Sophos;i="4.41,217,1241391600"; d="scan'208,217";a="201794229" Received: from 88-106-18-229.dynamic.dsl.as9105.com (HELO asus) ([88.106.18.229]) by smtp.tiscali.co.uk with ESMTP; 19 May 2009 21:57:37 +0100 From: "Gary - G4WGT" To: "LF -RSGB LF Group" Date: Tue, 19 May 2009 21:57:38 +0100 Message-ID: <003001c9d8c4$719e7710$6401a8c0@asus> MIME-Version: 1.0 X-Mailer: Microsoft Office Outlook 11 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.3350 Thread-Index: AcnYxHEIVXgQmgLaTg2y/yhIDv4DXg== X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: 518khz - Notch Filter. Content-Type: multipart/alternative; boundary="----=_NextPart_000_0031_01C9D8CC.D362DF10" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.1 required=5.0 tests=HTML_60_70,HTML_MESSAGE 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-IP: 193.82.116.20 ------=_NextPart_000_0031_01C9D8CC.D362DF10 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Hi LF, You may have seen an image of a NAVTEX signal on my 500KHz grabber at about 506KHz. The original of this image is at 518KHz. The receiver for this grabber is a Softrock Lite 455KHz module modified for 500KHz. I have attempted to notch the signal using a simple series or parallel filter but only succeeded in seriously degrading the whole band possibly due to the bandwidth of the filter?? Is there some simple narrow notch filter which I could use to remove the offending signal. 73, Gary - G4WGT - IO83QP. ------=_NextPart_000_0031_01C9D8CC.D362DF10 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

Hi LF,=

 =

You may have seen an image of a= NAVTEX signal on my 500KHz grabber at about 506KHz. The original of this image is a= t 518KHz. The receiver for this grabber is a Softrock Lite 455KHz module modif= ied for 500KHz.

 =

I have attempted to notch the s= ignal using a simple series or parallel filter but only succeeded in seriously degrading the whole band possibly due to the bandwidth of the filter??

 =

Is there some simple narrow not= ch filter which I could use to remove the offending signal.

 =

73,

 

Gary - G4WGT - IO83QP.=

 

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