Return-Path: Received: (qmail 12401 invoked from network); 2 Oct 2001 00:06:22 -0000 Received: from unknown (HELO murphys-inbound.services.quay.plus.net) (212.159.14.225) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 2 Oct 2001 00:06:22 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 22233 invoked from network); 2 Oct 2001 00:06:04 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by murphys with SMTP; 2 Oct 2001 00:06:04 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15oCzy-0000wt-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 02 Oct 2001 01:01:22 +0100 Received: from imo-r02.mx.aol.com ([152.163.225.98]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 15oCzx-0000uR-00 for rsgb_lf_group@blacksheep.org; Tue, 02 Oct 2001 01:01:21 +0100 Received: from MarkusVester@aol.com by imo-r02.mx.aol.com (mail_out_v31_r1.7.) id l.6d.1b380496 (4315) for ; Mon, 1 Oct 2001 20:00:37 -0400 (EDT) From: MarkusVester@aol.com Message-ID: <6d.1b380496.28ea5da4@aol.com> Date: Mon, 1 Oct 2001 20:00:36 EDT Subject: LF: FS measurements, EMRP calculations To: rsgb_lf_group@blacksheep.org MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Mailer: AOL 4.0.i for Windows 95 sub 72 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Dear group, here comes a log of stations received last weekend: UT kHz call dBµV/m dist Friday, 28.9.01: 2204 136.7 OK1FIG +13 376km? beginning of our QSO 2018 OK1FIG +23 end of QSO (nighttime QSB) 2027 136.5 EI0CF +11 2330 71.924 M0BMU ? 841km 2330 71.9215 G3AQC 0.1 Hz DFCW Saturday, 29.9.01: 0925 136.9 OK1FIG +19 stable daytime level 136.66 DL3FDO +23 197km 136.9 PA0BWL +7 474km 136.9 DF0WD +14 357km 137.3 DJ5DI +4 1315 136.83 OM2TW +10 496km? 136.83 DF0WD +15 136.83 SM6PXJ +3 1035km 136.5 G3KEV +9 963km 136.8 DK6NI +28 20km 1435 136.8 OM5CW 2330 135.923 M0BMU +0...+6 QSB Sunday, 30.9.01: 0857 136.59 DL5WF +4 135km? 136.69 G3KEV +6 136.76 OM2TW +7 136.61 OK1FIG +18 0903 136.54 DK6NI +28 20km 136.76 OM2CW +7 136.76 DL3FDO +22 0922 136.76 DJ7RD +26 129km 137.16 carrier 0 FSK bursts 1.8s, bear. 285° 136.68 carrier -1 FSK bursts 40s, bear. 285° 136.549 DCF IM -11 165km (reduced since 22.09.01) 135.36 DCF IM +28 165km 0938 136.6 SM6PXJ -2 0940 136.7 G3KEV +9 136.7 DK3GH +24 23km 136.56 M0BMU +2 1040 137.59 OM2TW +6 QRSS/DFCW QSO 1209 136.7 DK7SU +10 136.9 OZ8NJ +6 436km 1910 138.83 DBF39 +68 310km The fieldstrength measurements were taken from calibrated spectrogram readings and should be accurate to a couple of dB's. Given the distance d from my QTH (JN59NK), you can estimate your radiated power by the formula EMRP /dBW = FS /dBµV/m - 79.55 + 20 lg (d /km) + GL /dB. The additional ground-wave loss GL is generally neglegible for distances up to 100 km. Assuming no ionospheric propagation (which is not valid for long-distance paths, especially in darkness), GL can be estimated from the CCIR ground-wave charts, and for average soil conductivity (land, 3 mS/m) one gets a table like this d/km GL/dB 1 0 100 1 200 3 300 5 400 8 500 9 600 12 800 17 1000 22 1500 31 73 de Markus, DF6NM