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Old June 13th 05, 07:40 PM
Wes Stewart
 
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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?