Return-Path: Received: from rly-df06.mx.aol.com (rly-df06.mail.aol.com [172.19.156.19]) by air-df01.mail.aol.com (v121_r2.12) with ESMTP id MAILINDF013-55a48b2fcc3396; Mon, 25 Aug 2008 14:41:34 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-df06.mx.aol.com (v121_r2.11) with ESMTP id MAILRELAYINDF065-55a48b2fcc3396; Mon, 25 Aug 2008 14:41:10 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1KXgzS-0007M4-1E for rs_out_1@blacksheep.org; Mon, 25 Aug 2008 19:40:34 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1KXgzR-0007Lv-Kz for rsgb_lf_group@blacksheep.org; Mon, 25 Aug 2008 19:40:33 +0100 Received: from sighthound.demon.co.uk ([80.177.174.126]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1KXgzP-0003Ql-8H for rsgb_lf_group@blacksheep.org; Mon, 25 Aug 2008 19:40:33 +0100 Received: from lurcher.twatt.local (lurcher.twatt.local [192.168.1.4]) by lurcher.twatt.local (Postfix) with ESMTP id 75D5424A010 for ; Mon, 25 Aug 2008 19:40:46 +0100 (BST) Date: Mon, 25 Aug 2008 19:40:46 +0100 From: John Pumford-Green To: rsgb_lf_group@blacksheep.org Message-ID: <20080825194046.53199091@lurcher.twatt.local> In-Reply-To: <002401c906de$82e26030$0301a8c0@mal769a60aa920> References: <000d01c9052d$6f142c30$0301a8c0@mal769a60aa920> <003e01c90543$b12bb870$0301a8c0@mal769a60aa920> <20080823193946.20d4b66b@sighthound.demon.co.uk> <005701c90555$0018bcb0$0301a8c0@mal769a60aa920> <9256A09B44B94949B34506B5E7260A84@AGB> <20080824233353.muhlmpin3r34kggk@webmail4.kuleuven.be> <002401c906de$82e26030$0301a8c0@mal769a60aa920> Organization: The Gammy Bird X-Mailer: Claws Mail 3.3.1 (GTK+ 2.12.9; i486-pc-linux-gnu) Mime-Version: 1.0 X-Karma: 0: X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: 500khz rtty Content-Type: text/plain; charset=US-ASCII 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-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_helo : n X-AOL-SCOLL-AUTHENTICATION: listenair ; SPF_822_from : n On Mon, 25 Aug 2008 19:15:10 +0100 "mal hamilton" wrote: > I have maximum advantage with the permitted power How do you verify your ERP? Your NoV application must have included some indication of how you would do it. How do you ensure your TX power is not excessive, given the self proclaimed superior location and antenna? As you say, local measurement of field strength is only the way to do it. I've done it, many times, using a laboratory standard, calibrated, professional MF field strength meter, as well as my own home designed (I can provide you with the maths for it) loop antenna and calibrated receiver. My take off is similarly uncluttered to yours and I've measured FS at ranges between 600m and 3km, in all directions around my TX antenna. I presume, as the professional radio experimenter (not appliance operator) that you are, that you've done likewise? I'd be interested in your results. Can you give an indication of the overall loss resistance, the radiation resistance and radiation efficiency of your wonderful 100' high 1/4 wave inverted-L, and the resultant estimation of maximum TX power allowable to remain below 1W ERP? I guess you'll have these figures to hand, since you are one of the most technically able, numerate and scientific of the LF/MF community, by your own, frequent, admission.