Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-0.2 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_MED,SPF_PASS,STOX_REPLY_TYPE,STOX_REPLY_TYPE_WITHOUT_QUOTES, T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.0 X-Spam-DCC: EATSERVER: mailn 1166; Body=2 Fuz1=2 Fuz2=2 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by lipkowski.org (8.14.4/8.14.4/Debian-8+deb8u1) with ESMTP id v3OAw1CT009692 for ; Mon, 24 Apr 2017 12:58:02 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1d2bZD-0003HN-H2 for rs_out_1@blacksheep.org; Mon, 24 Apr 2017 11:50:03 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1d2bZC-0003HE-L0 for rsgb_lf_group@blacksheep.org; Mon, 24 Apr 2017 11:50:02 +0100 Received: from rgout0207.bt.lon5.cpcloud.co.uk ([65.20.0.206] helo=rgout02.bt.lon5.cpcloud.co.uk) by relay1.thorcom.net with esmtp (Exim 4.89) (envelope-from ) id 1d2bZ9-0000XT-IK for rsgb_lf_group@blacksheep.org; Mon, 24 Apr 2017 11:50:01 +0100 X-OWM-Source-IP: 109.156.197.114 (GB) X-OWM-Env-Sender: alan.melia@btinternet.com X-Junkmail-Premium-Raw: score=8/50,refid=2.7.2:2017.2.14.234516:17:8.707,ip=,rules=NO_URI_FOUND, NO_CTA_URI_FOUND, NO_MESSAGE_ID, NO_URI_HTTPS, TO_MALFORMED Received: from gnat (109.156.197.114) by rgout02.bt.lon5.cpcloud.co.uk (9.0.019.13-1) (authenticated as alan.melia@btinternet.com) id 58482B970E9B7554 for rsgb_lf_group@blacksheep.org; Mon, 24 Apr 2017 11:49:58 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=btinternet.com; s=btcpcloud; t=1493030999; bh=0uF1/Jlv4HlMoCiznzpF7A09tARTKirRdxyhiekhuwI=; h=Message-ID:From:To:References:Subject:Date:MIME-Version:X-Mailer; b=R+6oGzEzWhAjejvAXoejwZJ15tSe9alPQH5zT1rJ8dl2/mEhwR8I9GvgTTZTrnZQsHHlwP3IalwCOoFmvGP4rU6v7CK3Nf3XJmeD+PJmhpEdrMDfYKFslbfdQBMUBh8T8i+o7QtjUTEBqLRh7ui/G88+RcObBCZ7aemDYvR7iLA= Message-ID: From: "Alan Melia" To: References: <2829407.clpKmQlE6b@fbox> Date: Mon, 24 Apr 2017 11:49:55 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 X-Scan-Signature: e6de17d69e46ff4ea8db042ef2cd7e46 Subject: LF: Re: Thanks for all the LF reports Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit 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-Scanned-By: MIMEDefang 2.75 Status: RO X-Status: X-Keywords: X-UID: 11451 Colin the wavy line you display as your QRM is almost certainly a switched -mode power supply. the line at 1400 is a harmonic of the switching frequency and this is modulated by 100Hz giving the sidebands. If you wind out the bandwidth you may see other harmonics, the interval between the central lines gives the switcher fundamental. This can help to identify it. A note of the times it appears with respect to local human activity can give a clue where it is. Altenatively a bit of DF with a loop aerial (always useful to have at LF) might locate it. It might be one of your own family devices or it may only occur when your neighbours are at home. A little "detective work" can identify the source and often arrange a replacement which is quieter. Good Luck with it Alan G3NYK ----- Original Message ----- From: "Colin J Thomson" To: Sent: Monday, April 24, 2017 12:28 AM Subject: LF: Thanks for all the LF reports > Hi MF/LF > > I would just like to say thanks for all the reports on OP32 and WSPR on > 136k > from a small QRP station this end. > > Sadly due to QRM here I do not copy many stations.. See attached of the > QRM > that appears now and then. > > 73 Colin - G6AVK > -- > Fedora 25 (Twenty Five) > Registered Linux user number #342953 >