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On 13 Jun 2005 08:20:08 -0700, "Al" wrote:
With just a cursory look I see that you sell "beems" instead of "beams" Look a little more and you will find more typo's I am sure. Let me tell you a little war story and see what you think. About 20 years ago my boss, a newly minted PhD, got a job teaching a Senior/Graduate level course on Microwave Measurements Theory and Practice at the U of AZ. At the time the U's equipment was abysmal so he got permission to bring the kids into my lab at Hughes for the lab portion of the class. I got the job of devising the experiments, setting up the gear and grading the lab notebooks. The kids could absolutely not see straight when I graded their grammar. Their cry was, "This is an engineering course, not an English course." My reply was that they were prepping themselves for a job in industry (actually a few of them already worked at Hughes) and I wrote memos and reports every day, that if poorly written would reflect badly on me. Your web site is your place of business...fill it up with typos, bad grammar and bogus claims and your business can suffer. On second thought, considering your client base, maybe they'll never notice. and a claim that corner reflectors work better on packet than do Yagis is pure snake oil. I think I said long Yagi's, something to do with phase distortion. I am just going by what customers have told me that have used both. Aha. So all I have to do is buy one of your antennas and write and tell you how awful it works and you'll put that on your web site. Simply modeling your super J-pole and adding a third element to represent the transmission line would show that the line radiates like crazy and affects the feedpoint Z. I never said anything about a "super J-Pole" . Sorry, a facetious remark that escaped you. Other than maybe it is super simple. If you simply modeled the OSJ and it showed the feed line radiates like crazy, Maybe you didn't do it right. Maybe you need to step out into the real world. By the way, it has a 3rd element, makes it a dual J-Pole not just a dual band. No, I modeled the OSJVHF as depicted he http://www.arrowantennas.com/inst/igif/ijmurs1.gif You claim 150-162 MHz with 1.5:1 SWR. I modeled it as follows. I saw the SWR vary from a low of 1.4:1 at 150 MHz to a high of almost 7:1 at 162 MHz. Here's the file: ************************************************** ********************* EZNEC+ ver. 4.0 Created from MultiNEC 6/13/2005 11:25:41 AM --------------- ANTENNA DESCRIPTION --------------- Frequency = 150 MHz Wire Loss: Aluminum (6061-T6) -- Resistivity = 4E-08 ohm-m, Rel. Perm. = 1 --------------- WIRES --------------- No. End 1 Coord. (in) End 2 Coord. (in) Dia (in) Segs Insulation Conn. X Y Z Conn. X Y Z Diel C Thk(in) 1 W4E1 0, 0, 0 W2E1 0, 0, 18 0.375 13 1 0 2 W1E2 0, 0, 18 0, 0, 54 0.375 26 1 0 3 W4E2 0, 5, 0 0, 5, 18 0.375 13 1 0 4 W1E1 0, 0, 0 W3E1 0, 5, 0 0.375 4 1 0 Total Segments: 56 -------------- SOURCES -------------- No. Specified Pos. Actual Pos. Amplitude Phase Type Wire # % From E1 % From E1 Seg (V/A) (deg.) 1 1 0.00 3.85 1 1 0 SI No loads specified No transmission lines specified Ground type is Free Space ************************************************** ********************* Where did I go wrong? |