Return-Path: Received: (qmail 17996 invoked from network); 26 Aug 2001 01:10:38 -0000 Received: from unknown (HELO warrior-inbound.services.quay.plus.net) (212.159.14.227) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 26 Aug 2001 01:10:38 -0000 Received: (qmail 14599 invoked from network); 26 Aug 2001 01:09:00 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 26 Aug 2001 01:09:00 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15aoLH-0004uF-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 26 Aug 2001 02:03:59 +0100 Received: from mta5-rme.xtra.co.nz ([203.96.92.17]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 15aoLF-0004mw-00 for rsgb_lf_group@blacksheep.org; Sun, 26 Aug 2001 02:03:58 +0100 Received: from xtr743187 ([202.27.178.49]) by mta5-rme.xtra.co.nz with SMTP id <20010826010244.YICD632.mta5-rme.xtra.co.nz@xtr743187> for ; Sun, 26 Aug 2001 13:02:44 +1200 Message-ID: <008201c12dca$d5b90240$88b21bca@xtr743187> From: "Vernall" To: rsgb_lf_group@blacksheep.org References: <149.7b0813.28b8e0b8@aol.com> Subject: LF: Re: Re: Carriers Date: Sun, 26 Aug 2001 13:00:13 +1200 MIME-Version: 1.0 Content-Type: text/html; charset=windows-1252 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2919.6600 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Content-transfer-encoding: 8bit

Wolf DL4YLF,

OK on receiving 50 Hz hum modulation from TV sets.

>I guess most of the QRM travels over the mains supply lines. I already
>considered building a battery-powered remove RX with a 70cm-FM-link to the
>main station (using a cheap 70cm-LPD handy). The problem is finding a quiet
>remote RX side where the RX cannot be vandalized or stolen.

Several ZL amateurs, including myself, have had quite good results in minimising LF QRM by using an active whip antenna sited somewhat away from houses (and their mains wiring). Attention needs to be paid to RF isolation of the power supply for the antenna, and using balance RF transmission lines, otherwise the mains QRM can still get to the antenna via the shack and feeder. 5 metres or so separation of an active whip from house wiring can greatly reduce the mains-conducted QRM, but is still good for receiving wanted DX signals.

73, Bob ZL2CA