[From nobody Thu Jul 3 13:42:05 2003 Return-Path: <owner-lowfer@ns3.qth.net> Received: from ns3.qth.net ([207.204.29.187]) by immta4.bellatlantic.net (InterMail vM.4.01.02.27 201-229-119-110) with ESMTP id <20000521000005.TNPZ1451.immta4.bellatlantic.net@ns3.qth.net>; Sat, 20 May 2000 20:00:05 -0400 Received: (from majordom@localhost) by ns3.qth.net (8.9.3/8.9.3) id TAA23199 for lowfer-outgoing; Sat, 20 May 2000 19:50:46 -0400 Received: from motgate.mot.com (motgate.mot.com [129.188.136.100]) by ns3.qth.net (8.9.3/8.9.3) with ESMTP id TAA23195 for <lowfer@qth.net>; Sat, 20 May 2000 19:50:44 -0400 Received: [from mothost.mot.com (mothost.mot.com [129.188.137.101]) by motgate.mot.com (motgate 2.1) with ESMTP id QAA14681 for <lowfer@qth.net>; Sat, 20 May 2000 16:50:43 -0700 (MST)] Received: [from tx14exm01.ftw.mot.com (tx14exm01.fwrdc.rtsg.mot.com [178.1.100.241]) by mothost.mot.com (MOT-mothost 2.0) with ESMTP id QAA06300 for <lowfer@qth.net>; Sat, 20 May 2000 16:50:43 -0700 (MST)] Received: by tx14exm01.fwrdc.rtsg.mot.com with Internet Mail Service (5.5.2650.21) id <KRNYFA3H>; Sat, 20 May 2000 18:50:43 -0500 Message-ID: <49D27106E5DAD3118E030008C7CF80458080EA@tx14exm01.fwrdc.rtsg.mot.com> From: Cantrell Bill-QA0057 <Bill_Cantrell-QA0057@email.mot.com> To: "'Tim Pauly'" <tpauly@twcny.rr.com>, lowfer@qth.net Subject: RE: [Lowfer] Different types of antennae Date: Sat, 20 May 2000 18:50:37 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-lowfer@qth.net Precedence: bulk Reply-To: Cantrell Bill-QA0057 <Bill_Cantrell-QA0057@email.mot.com> X-Mozilla-Status2: 00000000 Tim, On a mobile BPSK reception experiment through Arkansas, I noticed that very tall trees along the median of the Interstate Hiway would attenuate weak-signal LF reception, even though the trees were ~40 to 50 feet away from the roadway, but they were also ~50 to 80 feet tall] This made the difference between E-field probe reception (using BPSK GRAB) and no signal. That is, I could receive the signal only if there were none of these trees in the median. So if you can get MORE THAN 100 feet away from trees that are 100 feet tall, then that may be good enough. (I am assuming that the effect of trees on reception would be reciprocal to transmission.) Regards, Bill "TEXAS" & WD5CVG -----Original Message----- From: Tim Pauly [mailto:tpauly@twcny.rr.com] Sent: Saturday, May 20, 2000 2:27 PM To: lowfer@qth.net Subject: Re: [Lowfer] Different types of antennae On Sat, 20 May 2000 14:10:24 -0500, Lyle Koehler wrote: >hat on your 40-foot tower and feed it the way Bruce, W0BK does for his >BK beacon. In the winter the trees freeze and become fairly good >insulators. More details on my web page at >http://www.computerpro.com/~lyle under "Listening for LowFERs, Part 2" >and the description of the BEAMHAT.ANT models under "Computer Modeling How 'close' to trees is too close? I could put a ground mounted vertical in the front of the house which would be open from trees for at least 80-100 feet in 3 directions. But it is also at the base of the hill, and the top of the antenna would be at house level (about 15 feet from the house). You'd have to see the way this crazy place is laid out to know what I mean. Our house is literally situated on the side of a very steep valley. The house itself is about 40 feet above street level (lots of steps to carry groceries up!). My tower is about 50-60 feet behind the house, but the base of it is above the second floor level (like I said, we're on the side of a very steep valley!) Also, my tower is grounded and mounted with threaded rod set in concrete. Unless I made a "folded unipole" out of it ;-) I don't think it would work well. There is also VHF transmit antenna already mounted on it, and a UHF relay antenna will be going on it soon... Tim To unsubscribe, send to MAJORDOMO@qth.net "unsubscribe lowfer" (Do not send to list!!) Send on list submissions to lowfer@qth.net To unsubscribe, send to MAJORDOMO@qth.net "unsubscribe lowfer" (Do not send to list!!) Send on list submissions to lowfer@qth.net ]