Return-Path: Received: (qmail 1623 invoked from network); 3 Dec 2001 23:25:13 -0000 Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 3 Dec 2001 23:25:13 -0000 Received: (qmail 14835 invoked from network); 3 Dec 2001 23:25:24 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 3 Dec 2001 23:25:24 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16B2Ol-0006uS-00 for rsgb_lf_group-outgoing@blacksheep.org; Mon, 03 Dec 2001 23:21:19 +0000 Received: from latimer.mail.uk.easynet.net ([195.40.1.40]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16B2Oj-0006uN-00 for rsgb_lf_group@blacksheep.org; Mon, 03 Dec 2001 23:21:17 +0000 Received: from ericadodd (tnt-1-29.easynet.co.uk [195.40.206.29]) by latimer.mail.uk.easynet.net (Postfix) with SMTP id 9520053A17 for ; Mon, 3 Dec 2001 23:20:30 +0000 (GMT) Message-ID: <002501c17c51$90cc7c40$1dce28c3@ericadodd> From: "g3ldo" To: rsgb_lf_group@blacksheep.org References: <5.1.0.14.0.20011203115739.00aded78@gemini.herts.ac.uk> Subject: LF: Re: 137k tests/73k on 1/2 Dec Date: Mon, 3 Dec 2001 23:23:00 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: James Moritz said > I worked through the FS figures I measured last week on 73k - it comes out > like this: > > G3AQC 130mW ERP > G3LDO 85mW ERP > M0BMU 100mW ERP > > Rugby 73.25kHz 7.5kW ERP > > Bearing in mind that for all the signals apart from my own, deviation of up > to +/-3dB could be expected due to relying on only one field strength > measurement, and that I have not attempted to include ground wave losses. > So amateur signals are roughly 50dB down compared to the Rugby FSK signal. > If the receiver is using about 0.01Hz bandwidth to obtain a few dB SNR (ie > a visible QRSS signal), then the FSK should have at least 6dB SNR in 300Hz > BW, so be an easily audible signal. Jim's figures look about right. I was running about 800w and I figure my antenna is about .01% efficient. I hope to get a new or repaired third module for the Decca Tx this week and should be able to get up to 120mW erp if I also get a better PSU! I wont be on 73kHz tonight or tomorrow. Regards, Peter, G3LDO e-mail Web