Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mk04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 7B784380000B1; Wed, 7 Sep 2011 17:25:22 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1R1Pb2-0003GY-Eg for rs_out_1@blacksheep.org; Wed, 07 Sep 2011 22:23:48 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1R1Pb1-0003GP-Sc for rsgb_lf_group@blacksheep.org; Wed, 07 Sep 2011 22:23:47 +0100 Received: from mail16.primus.ca ([216.254.141.183] helo=mail-08.primus.ca) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1R1Pay-0001jX-Rl for rsgb_lf_group@blacksheep.org; Wed, 07 Sep 2011 22:23:47 +0100 Received: from dyn-dsl-bb-98-124-1-94.nrtco.net ([98.124.1.94] helo=Bigmachine.magma.ca) by mail-08.primus.ca with esmtpa (Exim 4.72) (envelope-from ) id 1R1Pax-0001PN-1G for rsgb_lf_group@blacksheep.org; Wed, 07 Sep 2011 17:23:43 -0400 X-Mailer: QUALCOMM Windows Eudora Version 7.1.0.9 Date: Wed, 07 Sep 2011 17:24:07 -0400 To: rsgb_lf_group@blacksheep.org From: Bill de Carle In-Reply-To: References: <4E6695F9.8060402@iup.uni-heidelberg.de> <4E6727E8.5040508@iup.uni-heidelberg.de> <4E676569.5030207@iup.uni-heidelberg.de> <4E6776EC.8090202@iup.uni-heidelberg.de> <4E67989F.9040000@iup.uni-heidelberg.de> <4E67AF85.7000002@iup.uni-heidelberg.de> Mime-Version: 1.0 X-Authenticated: ve2iq - dyn-dsl-bb-98-124-1-94.nrtco.net (Bigmachine.magma.ca) [98.124.1.94] X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Message-Id: Subject: LF: Effects of noise burst Content-Type: text/plain; charset="us-ascii"; format=flowed X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.63 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-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:393019584:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d61884e67e142305a X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none I noticed my marker line was getting chopped up at times on both Spectrum Lab screens. At first I thought it was another strong carrier off-screen for the SL display but still within the 500-Hz Cw filter's passband. There are several clearly *audible* signals in there at times. So I brought up ARGO for a wider view using 3-second dot mode. You can see my marker at 136.170 Khz along with several other much stronger signals. Around the middle of the time grab it seems as if everything went dead - in fact it was a 45-second burst of local noise. Not much of anything audible but I saw the S-meter jump up about 30 dB (cutting back the RF gain and making the other weaker signals disappear). Interesting how the background looks exactly the same during the noise burst as at other times. We don't *see* any noise here, we see the *absence* of all the usual signals. That noise is what chops up my marker lines on the two .usr spectrum lab screens. Although still full daylight here it's getting near supper time and people are turning on appliances. Things will quiet down later hopefully. Here's the ARGO screen: http://www.nrtco.net/~ve2iq/grabs/136argo.jpg Bill, VE2IQ