Return-Path: Received: (qmail 28694 invoked from network); 27 Jun 1999 01:45:28 +0100 Received: from magnus.plus.net.uk (HELO magnus.force9.net) (195.166.128.27) by guiness.force9.net with SMTP; 27 Jun 1999 01:45:28 +0100 Received: (qmail 23563 invoked from network); 27 Jun 1999 00:45:36 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by magnus.plus.net.uk with SMTP; 27 Jun 1999 00:45:36 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 10y2xl-0007xQ-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 27 Jun 1999 01:38:25 +0100 X-Priority: 3 X-MSMail-Priority: Normal Received: from [203.96.92.1] (helo=mta1-rme.xtra.co.nz) by post.thorcom.com with esmtp (Exim 3.02 #1) id 10y2xj-0007xC-00 for rsgb_lf_group@blacksheep.org; Sun, 27 Jun 1999 01:38:24 +0100 Received: from [202.27.178.244] by mta1-rme.xtra.co.nz (InterMail v04.00.02.07 201-227-108) with SMTP id <19990627004059.WOF3789.mta1-rme@[202.27.178.244]> for ; Sun, 27 Jun 1999 12:40:59 +1200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Message-ID: <37757092.1D26@xtra.co.nz> Date: Sun, 27 Jun 1999 12:30:11 +1200 From: "vernall" X-Mailer: Mozilla 3.01C-XTRA (Win95; I) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: RX loops References: <199906231701_MC2-7A7F-E9F5@compuserve.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org Sender: Prof R. Jennison wrote: > > Go for the biggest loop with the highest Q that you can get > 73. > Roger G2AJV Agreed. The fundamental parameter is APERTURE. The number of turns is really a sort of impedance matching arrangement, especially if a high impedance tuned load is used. But in the end it is SQUARE METRES of loop area that does the basic receiving. In ZL we have found that the minimum sized loop that can still receive with external QRN as the dominant noise source is for a loop with about 1.5 metres per side i.e. just over 2 square metres area. That is for 180 kHz. Smaller area than that gets dominated by noise in the receiving pre-amplifier. Bob ZL2CA