Return-Path: Received: (qmail 3898 invoked from network); 19 May 2000 22:51:46 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by bells.core.plus.net.uk with SMTP; 19 May 2000 22:51:46 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12svW0-000180-00 for rsgb_lf_group-outgoing@blacksheep.org; Fri, 19 May 2000 23:45:08 +0100 Received: from smtp11.bellglobal.com ([204.101.251.53]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 12svVz-00017s-00 for rsgb_lf_group@blacksheep.org; Fri, 19 May 2000 23:45:07 +0100 Received: from server1 (ppp145.on.bellglobal.com [206.172.245.145]) by smtp11.bellglobal.com (8.8.5/8.8.5) with SMTP id SAA12765 for ; Fri, 19 May 2000 18:51:13 -0400 (EDT) Message-ID: <000c01bfc1e3$0ab7ae10$0a00a8c0@server1.ThreeLakes.ca> From: "Larry Kayser" To: rsgb_lf_group@blacksheep.org Subject: LF: Re: Re: LF receivers Date: Fri, 19 May 2000 18:38:01 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.72.3110.5 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: Peter: >I am working on the Receiver chapter for the LF book and >What is your favorite receiver and how does it compare with others >that you might have tried? My favorite LF receiver is the family of receivers that were once used to maintain the microwave radio and long haul coax FDM analogue carrier systems. These instruments (radios) were made by a number of different companies, the one I have now is a Wandel and Golterman, AT-611, that covers 6 kHz to 18 MHz. This radio has a "stabilized" local oscillator system that will hold a frequency to less than a Hz over long periods of time. This class of radios have generally very superior IF filters, mine has a 24 Hz filter that makes the radio especially good at coping with loud signals that are nearby in frequency. There is generally no AGC in these radios as they are in fact selective volt meters in their original application. I have had a number of receivers for LF over the last few years, but when it comes time to go looking for weak signals, the W&G is the one that gets turned on. I have also made use of the ICOM PCR-1000 as an LF receiver. What I have done here is made up a list of internal birdies in the receiver in the LF range and then hooked up the antenna to it and gone signal hunting, checking with the list of birdies is important so I can interpret what I am hearing. The PCR-1000 is a compromise of compromises - it is not a good LF receiver but it will let you tune around and get familiar with the LF part of the band.