Return-Path: Received: (qmail 24904 invoked from network); 31 Jan 2001 09:59:23 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by extortion.plus.net with SMTP; 31 Jan 2001 09:59:23 -0000 Received: (qmail 19227 invoked from network); 31 Jan 2001 10:02:13 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 31 Jan 2001 10:02:13 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #1) id 14Ntyg-0003ED-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 31 Jan 2001 09:55:02 +0000 X-Priority: 3 Received: from [213.2.16.106] (helo=rsgb.org.uk) by post.thorcom.com with esmtp (Exim 3.16 #1) id 14Ntye-0003E3-00 for rsgb_lf_group@blacksheep.org; Wed, 31 Jan 2001 09:55:01 +0000 X-MSMail-Priority: Normal Received: from miked by rsgb.org.uk with SMTP (MDaemon.v2.8.7.5.R) for ; Wed, 31 Jan 2001 09:45:51 +0000 From: "Mike Dennison" X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 To: rsgb_lf_group@blacksheep.org Date: Wed, 31 Jan 2001 09:45:50 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: LF: Noise and ARGO AGC Message-ID: <3A77DECE.29800.1FB248@localhost> In-reply-to: <4.1.20010130222200.00bd08c0@pop.tiscalinet.it> References: <3A768E17.10488.252F00@localhost> X-Mailer: Pegasus Mail for Win32 (v3.12c) X-MDaemon-Deliver-To: rsgb_lf_group@blacksheep.org X-Return-Path: miked@mail.rsgbhq Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: IK1ODO wrote: > > we have to investigate why the noise suddenly drops around 7 a.m., but > not always ... ? I presumed the cause was the street lights, but the > timing is different. > I agree that this effect appears to be one of the reasons that a transatlantic QSO using 30s dots is unlikely. For this to happen, a good S/N must be available for several hours. Perhaps it would help if several people reported exactly when their noise went off at dawn on one particular day, perhaps this coming Sunday. Most of us are assuming that it is caused by something local, such as street lights or neighbours' SMPSUs in 'off' mode. A coordinated test will show whether the effect is random, or related to a specific time in UTC, or related to local sunrise (propagation based effect). Mike, G3XDV (IO91VT) http://www.lf.thersgb.net