Return-Path: Received: (qmail 15557 invoked from network); 22 Jan 2002 11:04:20 -0000 Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 22 Jan 2002 11:04:20 -0000 Content-Transfer-Encoding: 8bit Received: (qmail 19200 invoked from network); 22 Jan 2002 11:04:16 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 22 Jan 2002 11:04:16 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16Syfe-0005WX-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 22 Jan 2002 11:00:54 +0000 Received: from bob.dera.gov.uk ([192.5.29.90]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16Syfd-0005WS-00 for rsgb_lf_group@blacksheep.org; Tue, 22 Jan 2002 11:00:53 +0000 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id LAA25587; Tue, 22 Jan 2002 11:09:58 GMT Received: (qmail 23761 invoked from network); 22 Jan 2002 11:48:44 -0000 Received: from gauntlet.mail.dstl.gov.uk (192.168.9.10) by baton.dstl.gov.uk with SMTP; 22 Jan 2002 11:48:44 -0000 Received: by gauntlet.mail.dstl.gov.uk; id LAA25227; Tue, 22 Jan 2002 11:17:44 GMT Received: from unknown(172.17.128.171) by gauntlet.mail.dstl.gov.uk via smap (3.2) id xma025197; Tue, 22 Jan 02 11:17:16 GMT Received: from FRN-MAIL-R3.dstl.gov.uk (unverified) by mailguard.dstl.gov.uk (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Tue, 22 Jan 2002 11:06:22 +0000 Received: by frn-mail-r3.dstl.gov.uk with Internet Mail Service (5.5.2650.21) id ; Tue, 22 Jan 2002 10:59:34 -0000 Message-ID: <7D653C9C42F5D411A27C00508BF8803DCB9965@pdw-mail-r1.dstl.gov.uk> From: "Talbot Andrew" To: rsgb_lf_group@blacksheep.org Subject: LF: RE: Radiated power Date: Tue, 22 Jan 2002 10:59:33 -0000 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: 20 LOG (V1/V2)= 20dB down About 10 Watts - but still a lot. We all fall into that dB trap from time to time I bet !!!!!!! Andy An interesting number: If Jim's measurement of MM0ALM's field strength is right, at 50 uV/m, and assuming the distance between them is 600 kms mainly over a standard medium-conductivity land path then : According to the CCIR standard propagation curves (Vol 5, "Propagation in non-ionised media", Recommendation 368-4) a radiated power of 1 kW at 136 kHz from a short vertically-polarised monopole would produce a field strength at Jim's distance of 500 uV/m. Jim measured 50 uV/m so MM0ALM's radiated power must be 10 dB below 1 kW - 100 watts. Jim's measurements I have found to be pretty accurate in the past but if anyone else can make accurate field strength measurements perhaps they would do so next time MM0ALM comes on. -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.