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Old November 18th 05, 09:19 PM posted to rec.radio.amateur.antenna
Reg Edwards
 
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"Cecil Moore" wrote
That's what antenna modeling programs are for.


----------------------------------------------------------------------
Cec, You should realise it's a waste of time pointing people towards
computer programs which require a 6-weeks full-time training course to
understand what its all about. And which they don't possess anyway.

Especially when a few sentences of plain English can provide an
adequate explanation to the enquirer.
----
Regards, Reg.


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Old November 18th 05, 11:02 PM posted to rec.radio.amateur.antenna
 
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Reg Edwards wrote:
"Cecil Moore" wrote
That's what antenna modeling programs are for.


----------------------------------------------------------------------
Cec, You should realise it's a waste of time pointing people towards
computer programs which require a 6-weeks full-time training course to
understand what its all about. And which they don't possess anyway.

Especially when a few sentences of plain English can provide an
adequate explanation to the enquirer.
----
Regards, Reg.

Hi Reg., The question was certaintly not a few sentences of plain
English. If the enquirer had shortened his description to a few well
defined sentences he might have some answers by now.
The demo version of EZNEC is free, as are your programs. Niether
require 6 weeks to learn.
My advice is to model the antenna, or give more precise question(s).
Gary N4AST

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Old November 18th 05, 11:13 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Reg Edwards wrote:
Cec, You should realise it's a waste of time pointing people towards
computer programs which require a 6-weeks full-time training course to
understand what its all about.


Reg, if I can learn ELNEC in two years, anyone can do it. :-)
--
73, Cecil http://www.qsl.net/w5dxp
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Old November 19th 05, 04:28 AM posted to rec.radio.amateur.antenna
Paladin
 
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I guess that an old man who hasn't been into electronics very long.
But, I do possess a fair amount of common sense. I can see that
you guys can't or won't help me figure out my problem. Too many
issues here. Everyone has SOME area of excellence.
I just haven't found the right person who WILL help. Life is
filled
with people who can only see their way. Words are not as
powerful as IDEAS. Thanks for the "words", fellas.

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Old November 19th 05, 03:27 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Paladin wrote:
I guess that an old man who hasn't been into electronics very long.
But, I do possess a fair amount of common sense. I can see that
you guys can't or won't help me figure out my problem. Too many
issues here. Everyone has SOME area of excellence.
I just haven't found the right person who WILL help. Life is filled
with people who can only see their way. Words are not as
powerful as IDEAS. Thanks for the "words", fellas.


I think there are people willing to help but from your original
posting, there was not enough information for me to model your
antenna. I don't recall you even telling us the length of your
inv-V dipole. And what did you mean by "linear loaded"?
--
73, Cecil http://www.qsl.net/w5dxp


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Old November 19th 05, 05:00 PM posted to rec.radio.amateur.antenna
Paladin
 
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The elements are "linear-loaded" . They are folded back on
themselves.
The phsical length is 70ft.,But the electrical length is 210ft. long
!
Now, is this strange dipole a 140ft. long,OR is it 420ft. long ? ?
That's why the feedline is so much problem............I've built
over
2 doz. antennas;this one IS tricky ! I have only 1/8 acre of land;
Hence the problems with dipole lengths,and feedline lengths.....:-)

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Old November 19th 05, 05:15 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Paladin wrote:
The elements are "linear-loaded". They are folded back on themselves.
The phsical length is 70ft.,But the electrical length is 210ft. long


Something like this? (fixed font)

35' 35'
-------------------------+ +-------------------------
| |
+------------------------+ +------------------------+
| |
+------------------------+ +------------------------+
| |
| |
| |
feedline

How far apart are the adjacent wires spaced?
--
73, Cecil http://www.qsl.net/w5dxp
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Old November 20th 05, 04:04 PM posted to rec.radio.amateur.antenna
Paladin
 
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The wires are close. The builder used rotor feed line. 3 equal
lengths of wires 70ft. long
THAT make one element. there is one on the oppisite side.

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Old November 20th 05, 06:50 PM posted to rec.radio.amateur.antenna
Richard Harrison
 
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Default feedlines and strange intereactions

Paladin wrote:
"I just haven`t found the right person who will help."

Help, it seems, is the answer Paladin wants to hear. When you want to
put 8 pounds of crap in a 4-pound bag, life is often that way. You
quickly run out of good advice.

When a respondent says there`s no computer program to tell you how to
linearly-load an antenna wire, you are invited to prove him wrong. The
ARRL Antenna Book says:
"Since the dimensions and spacing of linear-loading devices vary greatly
from one antenna to another, the best way to employ this technique is to
try a length of conductor 10% to 20% longer than the difference between
the shortened antenna and the full-size dimension for the linear-loading
device. Then use te "cut-anhd-try" method, varying both the spacing and
length of the loading device to optimize the match."

You might write a program for that.

Best regards, Richard Harrison, KB5WZI

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Old November 19th 05, 07:41 AM posted to rec.radio.amateur.antenna
Reg Edwards
 
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"Cecil Moore" wrote
Reg Edwards wrote:
Cec, You should realise it's a waste of time pointing people

towards
computer programs which require a 6-weeks full-time training

course to
understand what its all about.


Reg, if I can learn ELNEC in two years, anyone can do it. :-)

====================================

Cec, What is ELNEC? OK, I can guess!

Quite truthfully, if you had pointed ME towards EZNEC then I am unable
even to download and un-zip it.

Acually, I do have a copy. Some years back Roy took pity on me and,
without any request from me, very kindly broke the rules and airmailed
me a free parcel of 3.25" floppy disks. It took me a week to print out
the instruction handbook and another 2 weeks just to read it by which
time I had forgotten what the problem was.

'Experts' should realise, from the manner in which questions are
written, the predicament some questioners are in and make allowances
instead of leaving them to flounder about in a sea of frustration and
despondency.

N4AST's comments are unworthy.
----
Regards, Reg.




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