Return-Path: Received: from rly-de12.mx.aol.com (rly-de12.mail.aol.com [172.19.170.148]) by air-de08.mail.aol.com (v123.4) with ESMTP id MAILINDE083-5204a1337833b7; Tue, 19 May 2009 18:49:57 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-de12.mx.aol.com (v123.4) with ESMTP id MAILRELAYINDE127-5204a1337833b7; Tue, 19 May 2009 18:49:41 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1M6Y7L-000724-9j for rs_out_1@blacksheep.org; Tue, 19 May 2009 23:49:03 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1M6Y7K-00071v-SJ for rsgb_lf_group@blacksheep.org; Tue, 19 May 2009 23:49:02 +0100 Received: from [193.252.22.190] (helo=smtp6.freeserve.com) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1M6Y7H-0005J6-1a for rsgb_lf_group@blacksheep.org; Tue, 19 May 2009 23:49:02 +0100 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3602.me.freeserve.com (SMTP Server) with ESMTP id 09C777000083 for ; Wed, 20 May 2009 00:48:52 +0200 (CEST) Received: from AGB (unknown [91.110.74.236]) by mwinf3602.me.freeserve.com (SMTP Server) with SMTP id 781E87000082 for ; Wed, 20 May 2009 00:48:49 +0200 (CEST) X-ME-UUID: 20090519224849492.781E87000082@mwinf3602.me.freeserve.com Message-ID: <717E88F7C87444BAB9ED1F169783E4A4@AGB> From: "Graham" To: References: <003001c9d8c4$719e7710$6401a8c0@asus> In-Reply-To: <003001c9d8c4$719e7710$6401a8c0@asus> Date: Tue, 19 May 2009 23:48:48 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8064.206 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8064.206 X-Karma: unknown: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: 518khz - Notch Filter. Content-Type: multipart/alternative; boundary="----=_NextPart_000_0071_01C9D8DC.5ACDEEE0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.2 required=5.0 tests=HTML_60_70,HTML_MESSAGE, MISSING_OUTLOOK_NAME 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_0071_01C9D8DC.5ACDEEE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Gary, Try a 10 dB attenuator in the ae feed or bigger one ?=20 G ... From: Gary - G4WGT=20 Sent: Tuesday, May 19, 2009 9:57 PM To: LF -RSGB LF Group=20 Subject: LF: 518khz - Notch Filter. Hi LF, =20 You may have seen an image of a NAVTEX signal on my 500KHz grabber at about=20= 506KHz. The original of this image is at 518KHz. The receiver for this grabb= er is a Softrock Lite 455KHz module modified for 500KHz. =20 I have attempted to notch the signal using a simple series or parallel filte= r but only succeeded in seriously degrading the whole band possibly due to t= he bandwidth of the filter?? =20 Is there some simple narrow notch filter which I could use to remove the off= ending signal. =20 73, =20 Gary - G4WGT - IO83QP. =20 ----------------------------------------------------------------------------= ---- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.287 / Virus Database: 270.12.34/2122 - Release Date: 05/19/09 0= 6:21:00 ------=_NextPart_000_0071_01C9D8DC.5ACDEEE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Gary,
 
Try a 10 dB  attenuator in the ae feed= or=20 bigger one  ?
 
G ...

Sent: Tuesday, May 19, 2009 9:57 PM
Subject: LF: 518khz - Notch Filter.

Hi=20 LF,

 

You may have seen=20 an image of a NAVTEX signal on my 500KHz grabber at about 506KHz. The origin= al=20 of this image is at 518KHz. The receiver for this grabber is a Softrock Lite= =20 455KHz module modified for 500KHz.

 

I have attempted=20 to notch the signal using a simple series or parallel filter but only succee= ded=20 in seriously degrading the whole band possibly due to the bandwidth of the=20 filter??

 

Is there some=20 simple narrow notch filter which I could use to remove the offending=20 signal.

 

73,=

 

Gary - G4WGT -=20 IO83QP.

 


No virus found in this incoming message.
Checked by AVG -=20 www.avg.com
Version: 8.5.287 / Virus Database: 270.12.34/2122 - Release=20 Date: 05/19/09 06:21:00
------=_NextPart_000_0071_01C9D8DC.5ACDEEE0--