Return-Path: Received: from rly-dg10.mx.aol.com (rly-dg10.mail.aol.com [172.19.151.94]) by air-dg06.mail.aol.com (v121_r5.5) with ESMTP id MAILINDG062-5fb496dd1181bf; Wed, 14 Jan 2009 06:48:59 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dg10.mx.aol.com (v121_r4.4) with ESMTP id MAILRELAYINDG106-5fb496dd1181bf; Wed, 14 Jan 2009 06:48:42 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1LN4EI-0007lB-OM for rs_out_1@blacksheep.org; Wed, 14 Jan 2009 11:48:14 +0000 Received: from [193.82.59.130] (helo=relay2.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1LN4EI-0007l2-6X for rsgb_lf_group@blacksheep.org; Wed, 14 Jan 2009 11:48:14 +0000 Received: from sighthound.demon.co.uk ([80.177.174.126]) by relay2.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1LN4EC-0002tL-Id for rsgb_lf_group@blacksheep.org; Wed, 14 Jan 2009 11:48:14 +0000 Received: from [127.0.0.1] (lurcher.twatt.home [10.0.0.8]) by rsync.twatt.local (Postfix) with ESMTP id 144793B67E for ; Wed, 14 Jan 2009 11:48:01 +0000 (GMT) Message-ID: <496DD0F1.5060104@sighthound.demon.co.uk> Date: Wed, 14 Jan 2009 11:48:01 +0000 From: John P-G User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <496D13FA.5010807@usa.net> <496D20F1.5060001@usa.net> In-Reply-To: X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=disabled,AWL=0.128 Subject: Re: LF: WSPR beacon on 136kHz Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit 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-IP: 193.82.116.20 X-Mailer: Unknown (No Version) James Moritz wrote: > John - your lack of trees is not such a bad thing on 136k, where they soak > up a lot of your TX power. Jim, LF, Yes, on this point I'd agree, and it's probably why I did okay on 500kHz, up to a point. However the lack of ANYTHING tall in the adjacent area makes it awfully tricky to hang any respectable amount of wire in the air. I could run a horizontal wire back the the chimney on the house, at about 8m agl, but I try to keep wire as far away as possible from the house - a great source of QRM. My 8m vertical with a few sloping radials is tuneable on 500kHz, with an efficiency of 0.5% or so, given the poor ground losses I have due to waterlogged peat and rock, but on 136 I think I'd struggle to radiate anything without resorting to some seriously high TX power - with all the problems of high volts and general arcy-sparky that would ensue. I did try the fibreglass pole at 12m but the severe weather soon saw to that. At its reduced height of 8m it's survived all that Shetland storms can throw at it. To go much higher I'd need to excavate holes and form some concrete blocks for holding guying points, and another for the mast base, and then I might get 15-20m or so, in scaffold pole. A tower is out of the question, for expense and visual impact. There's still nowhere for a long horizontal top load to run to, and stay a sensible height AGL. All in all, more engineering than I'm prepared to do, certainly at this time of year. Will look for more WSPR on 136. Cheers, John