From owner-qrp-l@Lehigh.EDU Fri Feb 28 22:45:52 1997 Received: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id WAA26701 for ; Fri, 28 Feb 1997 22:45:51 -0500 (EST) X-Received-x: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id WAA26701 for ; Fri, 28 Feb 1997 22:45:51 -0500 (EST) Received: from Lehigh.EDU ([127.0.0.1]) by fidoii.cc.lehigh.edu with SMTP id <35334-33476>; Fri, 28 Feb 1997 22:45:36 -0500 Received: from nss2.CC.Lehigh.EDU ([128.180.1.26]) by fidoii.cc.lehigh.edu with ESMTP id <34888-46274>; Fri, 28 Feb 1997 22:44:30 -0500 Received: from marceau.fm.intel.com (marceau.fm.intel.com [132.233.247.8]) by nss2.CC.Lehigh.EDU (8.8.5/8.8.5) with ESMTP id WAA217251 for ; Fri, 28 Feb 1997 22:44:21 -0500 Received: from fmmail.fm.intel.com by marceau.fm.intel.com (8.8.4/10.0i); Sat, 1 Mar 1997 03:44:20 GMT Received: (from ccmgate@localhost) by fmmail.fm.intel.com (8.7.4/8.7.3) id TAA02271 for qrp-l@lehigh.edu; Fri, 28 Feb 1997 19:40:10 -0800 (PST) Received: by ccm.fm.intel.com (ccmgate 3.2 #2) Fri, 28 Feb 97 19:40:09 PST Date: Fri, 28 Feb 97 15:11:00 PST Reply-To: Cecil_A_Moore@ccm.ch.intel.com Sender: owner-qrp-l@Lehigh.EDU Precedence: bulk From: Cecil A Moore To: "Low Power Amateur Radio Discussion" Subject: More G5RV-type info X-Listprocessor-Version: 8.1 beta -- ListProcessor(tm) by CREN Message-Id: <97Feb28.224536est.35334-33476+165@fidoii.cc.lehigh.edu> Status: RO I used my BASIC program to generate the following chart which shows the length of the 450 ohm matching section required for a G5RV-like dipole operating on 3.8 MHz, 7.2 MHz, and 10.125 MHz for all dipole lengths from 88 ft to 123 ft. 111 ft is an interesting length for people interested in 80m and 30m but not 40m. With a 17.75 ft 450 matching section ahead of the coax, EZNEC predicts a 50 ohm SWR of 1.6:1 on 3.735 MHz and a 50 ohm SWR of 2:1 on 10.125 MHz. Unfortunately, with these dimensions, there would be a 50 ohm SWR of 46:1 on 40m. :-( dipole 450 ohm matching section length 3.8MHz 7.2MHz 10.125 MHz 88 34.19 41.47 22.76 89 33.68 41.06 22.56 90 33.16 40.68 22.36 91 32.62 40.30 22.16 92 32.07 39.94 21.96 93 31.51 39.59 21.77 94 30.93 39.25 21.57 95 30.33 38.93 21.37 96 29.72 38.61 21.17 97 29.08 38.30 20.98 98 28.43 38.00 20.77 99 27.76 37.71 20.57 100 27.06 37.43 20.37 101 26.34 37.15 20.16 102 25.60 36.88 19.95 103 24.83 36.66 19.74 104 24.03 36.36 19.52 105 23.21 36.10 19.31 106 22.35 35.86 19.08 107 21.46 35.61 18.85 108 20.54 35.37 18.62 109 19.58 35.14 18.38 110 18.57 34.91 18.13 111 17.53 34.68 17.88 112 16.44 34.46 17.62 113 15.30 34.24 17.35 114 14.11 34.02 17.08 115 12.87 33.80 16.79 116 11.56 33.59 16.49 117 10.19 33.38 16.18 118 8.74 33.17 15.85 119 7.22 32.96 15.56 120 5.66 32.76 15.16 121 3.92 32.55 14.79 122 2.13 32.35 14.39 123 0.22 32.15 13.97 73, Cecil, W6RCA, OOTC