Return-Path: Received: from rly-dc06.mx.aol.com (rly-dc06.mail.aol.com [172.19.136.35]) by air-dc01.mail.aol.com (v121_r4.4) with ESMTP id MAILINDC012-b28497d921227; Mon, 26 Jan 2009 05:36:16 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dc06.mx.aol.com (v121_r4.4) with ESMTP id MAILRELAYINDC064-b28497d921227; Mon, 26 Jan 2009 05:36:04 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1LROni-0002OS-2X for rs_out_1@blacksheep.org; Mon, 26 Jan 2009 10:34:42 +0000 Received: from [193.82.59.130] (helo=relay2.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1LROnh-0002OJ-Im for rsgb_lf_group@blacksheep.org; Mon, 26 Jan 2009 10:34:41 +0000 Received: from mtaout01-winn.ispmail.ntl.com ([81.103.221.47]) by relay2.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1LROnf-0004Za-9Q for rsgb_lf_group@blacksheep.org; Mon, 26 Jan 2009 10:34:40 +0000 Received: from aamtaout04-winn.ispmail.ntl.com ([81.103.221.35]) by mtaout01-winn.ispmail.ntl.com (InterMail vM.7.08.04.00 201-2186-134-20080326) with ESMTP id <20090126103432.WUGP2989.mtaout01-winn.ispmail.ntl.com@aamtaout04-winn.ispmail.ntl.com>; Mon, 26 Jan 2009 10:34:32 +0000 Received: from [192.168.2.33] (really [82.22.240.81]) by aamtaout04-winn.ispmail.ntl.com (InterMail vG.2.02.00.01 201-2161-120-102-20060912) with ESMTP id <20090126103432.ZIFF22934.aamtaout04-winn.ispmail.ntl.com@[192.168.2.33]>; Mon, 26 Jan 2009 10:34:32 +0000 From: "Mike Dennison" To: John P-G , rsgb_lf_group@blacksheep.org Date: Mon, 26 Jan 2009 10:34:24 -0000 MIME-Version: 1.0 Message-ID: <497D91B0.1756.4B9405@mike.dennison.ntlworld.com> In-reply-to: <20090125194232.05798210@lurcher> References: <20090125092908.0aec06a4@lurcher>, <00d301c97f22$87d998d0$6401a8c0@asus>, <20090125194232.05798210@lurcher> X-mailer: Pegasus Mail for Windows (4.41) Content-description: Mail message body X-Cloudmark-Analysis: v=1.0 c=1 a=9YlaCzn6_68A:10 a=397G9KUbBrW53FixTm4A:9 a=s13HhLWobLUbyzjo5syp5txJkqYA:4 a=yRxf6xUzZFUA:10 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,none Subject: Re: LF: Re: WSPR 503.5 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 GM4SLV wrote: > There was much discussion on the WSPR forum on the merits or otherwise > of this approach, in the HF sphere at least. > > It might be easier if we adopted the same approach as is recommended > for HF use - to report the actual TX power, not ERP. This does not follow. On the HF bands the ERP is close to RF power, especially on the bands where WSPR is popular, and can therefore be used a a rough approximation. That is most certainly not the case on LF/MF. On 136kHz I have to run 800W RF to get 300mW ERP. Another station might need just 100W RF to achieve the same power. Although the ratio is smaller on 500kHz, there is still a huge discrepancy between the RF needed to achieve the same ERP for different stations. RF power is therefore meaningless. Mike, G3XDV ==========