Rebellion on NEC programs
Art Unwin
was
a very fruitfull area for the naysayers to argue because the attack on
the method of testing could never have closure and the naysayers with
the loudest voices continued to rein as the true experts with respect
to antennas and amateurs.
Then we had the onset of Mininec and Nec computer programs that
initially
was welcomed with open arms until program discrepancies began to show
up and the naysayers began to rein supreme again. We now have the
instance that programs are downright wrong when they cannot forecast
the shorting actions of electricity with respect to antennas! Since
amateurs are of different backgrounds those not knowlegable of science
will follow the naysayer with the loudest voice who believes as with
pornography new radio science when seen can obviously be recognised as
a bogus technology.
Thus hams who desire smaller and better antennas to use in the
hobby to compete with the bigger and better have no where to go in the
pursuit of the truth other than self satisfaction with their own
antenna set ups in silence, while those with the loudest voices
continue with the mantra that all is known about antennas because the
naysayers volume of denials of the new because of their ability to
recognise fraud when they see it. Now we are at the point where
naysayers have presented the arguement that antennas made of mesh
cannot be used at radiators
while on the other side we have a report that some hams use shopping
carts as radiators while waiting in spacious parking lots.
Now, after trashing the usefulnes of NEC programs by those who
"know" are taking on those whose experience of mesh radiators as being
feaseable who have decided to remain meek and silent rather than face
the wrath of those led by the loudest voice. Now the trend is to roll
back the science teachings of Einstein, Planck and others by verbal
agression so that a new antenna technology can emerge and slaughter
the sciences that some profess to know as "false just by visuallizing"
without the need for thought.
So what does the future hold for those here with an interest in
antennas as the title of this forum implies?
nm...@wt.net
> So what does the future hold for those here with an interest in
> antennas as the title of this forum implies?
I'm afraid an NEC program would only arouse my appetite without
fully bedding it down. Gopher anyone?
Jeff Liebermann
<arthu...@gmail.com> wrote:
>So what does the future hold for those here with an interest in
>antennas as the title of this forum implies?
Without calculations, math, engineering, and modeling, you can return
to the days of trial by combat, proof by assertion, cut-n-try, claims
of amazing performance, irreproducible results, witchcraft, magic,
etc.
Granted, there are limitations to NEC2 modeling software.
<http://en.wikipedia.org/wiki/Numerical_Electromagnetics_Code#Limitations>
Rather than abandon years of work simply because you have invented an
antenna that cannot be visualized, optimized, modeled, seen or
demonstrated, a more productive solution to your problem would be to
find (or write) a suitable modeling program that would quantify your
"mesh" antenna. If you find that NEC2 or NEC4 based programs are
unsuitable for your purpose, there may be specialized programs that
may work.
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Art Unwin
> On Sun, 8 Nov 2009 08:24:50 -0800 (PST), Art Unwin
>
> >So what does the future hold for those here with an interest in
> >antennas as the title of this forum implies?
>
> Without calculations, math, engineering, and modeling, you can return
> to the days of trial by combat, proof by assertion, cut-n-try, claims
> of amazing performance, irreproducible results, witchcraft, magic,
> etc.
>
> Granted, there are limitations to NEC2 modeling software.
> <http://en.wikipedia.org/wiki/Numerical_Electromagnetics_Code#Limitations>
> Rather than abandon years of work simply because you have invented an
> antenna that cannot be visualized, optimized, modeled, seen or
> demonstrated, a more productive solution to your problem would be to
> find (or write) a suitable modeling program that would quantify your
> "mesh" antenna. If you find that NEC2 or NEC4 based programs are
> unsuitable for your purpose, there may be specialized programs that
> may work.
>
> --
> Jeff Liebermann je...@cruzio.com
> 150 Felker St #D http://www.LearnByDestroying.com
> Skype: JeffLiebermann AE6KS 831-336-2558
In the mean time those you recognise errant sciences when they see
them dominate over all others who choose not to question their
perceptability of total forsight of what is right and what is wrong.
It is not my problem, as you say, because I didn't write a program
that would win the day, the programs are already there. It is just at
this time the naysayers have the forsight to say what is wrong which
requires rebellion against that which say what is correct.
Personaly I believe there is progress in designing a radiator that
recognises CW and CCW
transmissions that provides choice in selection of what polarization
is used. After all hams wish to communicate with all and have no wish
to be left out because of the poor choice of antenna to use.
For the same radiator to be useable on all frequencies that we
are not licensed to use is purely academic to our interests tho for
the sake of science and the art of antennas the possibilities of what
is perceived to be a discovery should be pushed aside
on the basis of those that recognise what is bad based on what they
perceive to have seen.
The real problem today is that what we have accepted as good for
antennas ala NEC computer programs is not being accepted as viable by
those who have visual forsight that takes precidence over the science
of NEC programs and physics of the dayare using the volume level of
their voices to persuade all to denounce same.
With this aproach being gradually accepted by those who remain
silent we are being pushed back to personal antenna measurement which
allows for assertions of incorrect use of testing which in effect
gives credence with hams that for antennas all is really known! After
all, it suggests that if mesh radiators were able to transmit all
amatuers would be using them, when they are not! Thus the naysayers
with undeniable visual forsight must be correct!
So now amateurs are on a roll having "proved that short circuits
occur when using mesh via naysayers from both sides of the pond, who
can now dismiss with confidence the demise of helical antenna design
change having convinced all that NEC programs have now been shown as
defective. Next the idea will prevail that sunspots are there in
abundance but cannot be utelized while hams continue to use radiators
that naysayers, using the same "ability to recognize pornography" when
"they" see it, use the same abilities
to recognise psuedo sciences to deny those that pursue experimentation
to achieve the
possibility of advances in the hobby.
Now it is labelled "my problem".......... (Yes Aussie, I am the
ART that they usually attack), as it was for all the previous
knowledgable hams with respect to science and antennas that fled
rather than argue with those that belong to the "no" group which have
the louder audibles that rule this group.
Richard Clark
wrote:
>Without calculations, math, engineering, and modeling, you can return
>to the days of trial by combat, proof by assertion, cut-n-try, claims
>of amazing performance, irreproducible results, witchcraft, magic,
>etc.
For Art, it has long been proven through auto de f� and in his honour
(sic) this forum should be renamed religious.radio.amateur.antenna.
73's
Richard Clark, KB7QHC
Dave
what does that sentence mean? can anyone provide a translation
please?
> It is not my problem, as you say, because I didn't write a program
> that would win the day, the programs are already there. It is just at
> this time the naysayers have the forsight to say what is wrong which
> requires rebellion against that which say what is correct.
again, is there a google translator that will help with this?
> Personaly I believe there is progress in designing a radiator that
> recognises CW and CCW
> transmissions that provides choice in selection of what polarization
> is used. After all hams wish to communicate with all and have no wish
> to be left out because of the poor choice of antenna to use.
There are many antennas that discriminate between polarizations.
Satellite antennas often have CW or CCW switchable polarizations.
There used to be some 11m beams that had vertical, horizontal, or
circular selections. It is relatively easy to do vertical/horizontal/
cw/ccw with a pair of crossed yagis or just crossed dipole elements
and 1/4 wave phasing lines.
> For the same radiator to be useable on all frequencies that we
> are not licensed to use is purely academic to our interests tho for
> the sake of science and the art of antennas the possibilities of what
> is perceived to be a discovery should be pushed aside
> on the basis of those that recognise what is bad based on what they
> perceive to have seen.
say what? i give up, seems to be a big rant about something that
doesn't make much sense.
> the louder audibles that rule this group.- Hide quoted text -
>
> - Show quoted text -
Dave
> On Sun, 08 Nov 2009 10:41:10 -0800, Jeff Liebermann <je...@cruzio.com>
> wrote:
>
> >Without calculations, math, engineering, and modeling, you can return
> >to the days of trial by combat, proof by assertion, cut-n-try, claims
> >of amazing performance, irreproducible results, witchcraft, magic,
> >etc.
>
> (sic) this forum should be renamed religious.radio.amateur.antenna.
>
> 73's
> Richard Clark, KB7QHC
is that what this is, some kind of religious ranting? reminds me of
fracky and his 'all antennas are fractal' and trying to claim he
invented them all.
Jeff Liebermann
wrote:
I intentionally left out religion, congressional action, hucksterism,
fluoridation, and collectivism from my list of what might happen
without proper antenna calculations. These are all functional
alternatives to doing the numbers, but also have serious social and
political difficulties.
Also, there is religion in ham radio. Once a year, during the last
weekend in June, a horde of antenna worshipers ascend to the nearest
mountain top and erect monumental temporary altars in an attempt to
communicate to the radio gods their petition for more sunspots and
"good DXing". For an entire day and night, this horde will feverishly
"pound the brass" and "eat the mic" to noisily waken the radio spirits
and thus hear their petition. Yes, ham radio has religion.
Richard Fry
____________
Note that NEC uses the research and equations of "The Masters" that
(allegedly) you revere, Art -- and which have proven valid and useful
for many decades prior to the appearance of NEC.
Computers using NEC software make it easier to apply such equations.
But accurate results when doing so require that
the NEC software is well understood, and properly used for the system
being modeled.
The accurate understanding, and proper use of NEC leads to valid
conclusions about antenna system performance.
RF
Tom Horne
> On Sun, 08 Nov 2009 12:26:14 -0800, Richard Clark <kb7...@comcast.net>
> wrote:
>
> >On Sun, 08 Nov 2009 10:41:10 -0800, Jeff Liebermann <je...@cruzio.com>
> >wrote:
>
> >>Without calculations, math, engineering, and modeling, you can return
> >>to the days of trial by combat, proof by assertion, cut-n-try, claims
> >>of amazing performance, irreproducible results, witchcraft, magic,
> >>etc.
>
> >(sic) this forum should be renamed religious.radio.amateur.antenna.
>
> I intentionally left out religion, congressional action, hucksterism,
> fluoridation, and collectivism from my list of what might happen
> without proper antenna calculations. These are all functional
> alternatives to doing the numbers, but also have serious social and
> political difficulties.
>
> Also, there is religion in ham radio. Once a year, during the last
> weekend in June, a horde of antenna worshipers ascend to the nearest
> mountain top and erect monumental temporary altars in an attempt to
> communicate to the radio gods their petition for more sunspots and
> "good DXing". For an entire day and night, this horde will feverishly
> "pound the brass" and "eat the mic" to noisily waken the radio spirits
> and thus hear their petition. Yes, ham radio has religion.
>
> --
> Jeff Liebermann je...@cruzio.com
> 150 Felker St #D http://www.LearnByDestroying.com
> Skype: JeffLiebermann AE6KS 831-336-2558
Is that what I was doing last field day. I could have sworn I was
putting up two jack up masts with commercial triband antennas on them
to practice radio in the field and have a little fun. How do I go
about getting my congregations ministry and worship committee to
except it as a religious retreat. The fact that we had a no alcohol
field day would get me part way there but antenna worship might come
across as idolatry to the more straight forward practitioners of more
traditional forms of religion. That brings up another item of faith.
I thought that the Amateur Radio Code specifically banned discussion
of religion via amateur radio. I take it you don't believe that
simple courtesy should apply to off the air discussions of amateur
radio. It's all good though you can just have the state militia band
play drums around the scaffold so my heresy cannot be heard when you
hang me for being the wrong religion. That worked for the puritans in
Boston low these many years ago.
--
Tom Horne, W3TDH
Richard Clark
wrote:
>Yes, ham radio has religion.
and Art proclaims to be its �ssiah:
"Gauss, forgive them
for they know naught what de/do"
Jeff Liebermann
wrote:
>On Nov 8, 6:00�pm, Jeff Liebermann <je...@cruzio.com> wrote:
>> Also, there is religion in ham radio. �Once a year, during the last
>> weekend in June, a horde of antenna worshipers ascend to the nearest
>> mountain top and erect monumental temporary altars in an attempt to
>> communicate to the radio gods their petition for more sunspots and
>> "good DXing". �For an entire day and night, this horde will feverishly
>> "pound the brass" and "eat the mic" to noisily waken the radio spirits
>> and thus hear their petition. �Yes, ham radio has religion.
>Is that what I was doing last field day.
Possibly yes. The reason behind Field Day and the origin of the term
"ham" have been lost to antiquity. In the past, they had some
meaningful purpose, but over the ages, all we have left is the ritual.
At some point, there possibly was a real and useful purpose to the
ritual of climbing mountains, erecting antennas, and chanting arcane
acronyms and cryptic abbreviations into the radios. As with
archeology, anything that cannot be explained is automatically
attributed to a religious purpose. Archeologists have excavated many
a brothel and erroneously proclaimed it an ancient temple. So it is
with Field Day. Lacking a suitable alternative explanation for such
unproductive and irrational behavior (other than mass insanity), the
only logical purpose for Field Day can be religious in nature.
>I could have sworn I was
>putting up two jack up masts with commercial triband antennas on them
>to practice radio in the field and have a little fun.
If you were having fun, it is not religion. Religion requires
suffering. In future Field Days, I suggest you attempt something more
ambitious, such as running on bicycle generator power. That should
make it a real religious experience.
>How do I go
>about getting my congregations ministry and worship committee to
>except it as a religious retreat.
You can't. Established religions do not recognize pagan rituals and
derivative practices. I'm afraid that Field Day apparently had its
origins in the former, which are an anathema to the established
religions. The only reason there hasn't been a crusade against ham
radio and its Field Day ceremony is that much of the symbology is
similar to those of the established religions. Next time you erect a
mast with cross arm, ask yourself of what it resembles.
>The fact that we had a no alcohol
>field day would get me part way there
We tried a 50-50 alcohol gasoline mix in the generator. Bad idea.
>but antenna worship might come
>across as idolatry to the more straight forward practitioners of more
>traditional forms of religion.
I don't think that will be a problem. For example, I offer a silent
prayer every time I use the ATM banking machine, hoping there will be
some cash left in my account. Yet, nobody has accused me of
worshiping the ATM banking machine. Similarly, nobody has ever
suggested that you are worshiping your radio or antenna. Well, maybe
the Collins S Line collectors may be an exception. As long as the
radio deity is invisible, uniformly distributed through the cosmos,
and can survive an audit, there shouldn't be a problem.
>That brings up another item of faith.
>I thought that the Amateur Radio Code specifically banned
>discussion of religion via amateur radio.
Well, perhaps religious discussions using code may be banned, but I
don't recall any such thing for other modes. Little wonder the FCC
dropped the code requirement. I've often suspected that the original
founders of ham radio were all attorneys, since possession of a ham
license also seems to entitle one to offer legal opinions and
interpretations.
>I take it you don't believe that
>simple courtesy should apply to off the air discussions of amateur
>radio.
Yep. I prefer complex courtesy. The problem with most over the air
discussions is that it's impossible to have a discussion, simple or
otherwise. The cause is also lost in antiquity. At some point in the
distant past, it was necessary to repeat ones transmission several
times due to interference, fading, and static. This was probably the
case with spark gap (the original broadband initiative). Like Field
Day, the purpose was lost in antiquity, leaving use with long winded
blow hards repeating themselves endlessly. Unless you want to engage
in multi-hour long conversations, the average conversation more
closely resembles a monolog. It's really difficult to be discourteous
if the listener has gone to watch TV waiting for their turn.
The problem was recognized long ago. The answer is contesting. The
contesting solution resulted in the opposite extreme. A conversation
consists of call sign, signal report, and some trivial identifier.
Courtesy and contesting are oxymorons, as it's almost impossible to
win a contest by being courteous. The exercise sounds more like
jamming than discourse. Contesting is not a solution to the courtesy
problem.
The digital modes have their own answer. Most conversations are
computer to computer. The dialogs are canned and carefully word
processed into political correctness. I don't know anyone that has
insulting macros saved in the PSK31 program. Digital modes have
simple courtesy, but also kinda dry conversations.
>It's all good though you can just have the state militia band
>play drums around the scaffold so my heresy cannot be heard when you
>hang me for being the wrong religion. That worked for the puritans in
>Boston low these many years ago.
That used to be the case up to about 10 years ago before cable TV,
satellite TV, and CC&R's. Operating during prime time would result in
the neighbors organizing a torch light parade to your doorstep,
complaining of TVI, and offering to lynch the offender by his own
antenna tower. I think you're fairly safe today, especially with
todays QRP radios, which can easily be hidden when the torch light
parade arrives.
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
JIMMIE
What the heck is this all about, I thought Art was going to rant about
how hams just sit around and model antennas and never actually build
them. That would have been funny.
Jimmie
Michael Coslo
> What the heck is this all about, I thought Art was going to rant about
> how hams just sit around and model antennas and never actually build
> them. That would have been funny.
Careful Jimmie, you'll upset that guy from Radiobanter.com if you don't
watch it! 8^)
But the rest of you take notice, and quit hijacking Art's thread here to
talk about field day. I want to hear about how NEC has it all wrong!
Sheesh!
- 73 de Mike N3LI -
Art Unwin
Consensus of the group say RF applied to a mesh will short or fuse.
NEC shows that it will not and that it will radiate.
On my home page I did the same thing and got an SWR curve
Therefore Art and NEC programs have got it all wrong.
This probably means that a faraday shield will short also, but that
needs a little more
consensus from the group as it would destroy the shielding of the
innards.
Therefore the NEC programs must have it all wrong!
Richard Clark
wrote:
> I want to hear about how NEC has it all wrong!
Was that the Google translation?
Richard Fry
> Consensus of the group say RF applied to a mesh will short or fuse.
> NEC shows that it will not and that it will radiate.
Art, did you forget about the NEC analysis linked below?
How much will your mesh antenna radiate, unless you have invented a
VERY heroic network to match it to typical transmission lines
(comments, please)?
http://i62.photobucket.com/albums/h85/rfry-100/Arts_Mesh_Antenna.jpg
RF
Art Unwin
Aluminum mesh, windows, insects
Wire dia .011", mesh 18 by 16
Per group analysis, wires will short.
Your analysis, shows it radiates
physical measurements of Art, shows radiation.
Conclusion
NEC faulty per the groups teachings
Art's actual measurements also false
per groups teachings
Future actions suggested
Repeat NEC with actual mesh sample measurements used.
Show mesh circuit currents
Apply RF to outside of actual faraday shield and document results.
Richard Fry
> Future actions suggested
> Repeat NEC with actual mesh sample measurements used.
> Show mesh circuit currents
> Apply RF to outside of actual faraday shield and
> document results.
And the "future actions" you suggest above should be
accomplished and scientifically documented by you, Art.
This mesh antenna is your design, after all.
RF
Richard Clark
wrote:
>On Nov 10, 10:16�am, Art Unwin <arthurun...@gmail.com> wrote:
>
>> Consensus of the group say RF applied to a mesh will short or fuse.
>> NEC shows that it will not and that it will radiate.
Being able to pick up only 'snippets' through the stovepipe, it would
seem that Art either damns or praises NEC according to the wind
blowing to his detriment or to his favor.
If there were any dispute with the "consensus" it would seem to be
simple enough to contribute engineering evidence rather than religious
testimony. Art recites NEC, but I don't see (and that is possibly due
to filtering of static) any NEC content in the fragments of Art's
hymnals that survive through to the willing suspension of disbelief.
W'ot? Ain't I demonstrandum? (the alpha and omega of Art's
intellectual proofs).
Art, you are going to need at least two more criminals up there on
calvary before you can draw a crowd of legionaries to throw dice at
your feet.
Art Unwin
> On Tue, 10 Nov 2009 13:00:38 -0800 (PST), Richard Fry <r...@adams.net>
Well that's the end of this thread! Clark and his followers now appear
to be moving towards accepting NEC and also that mesh will radiate
according to the physics portion of his degree in literature( assuming
he is following the teachings of physics that is extensively
used in literature and shakesphere) with honors for showing he
had no balls when dancing in mesh tights at his hide out! It would
appear that the group is in disarray over whether Clark is to be
followed with respect to R.F. having the same characteristics of D.C.
current when applied to a mesh conductor. When you all make up your
minds whether a mesh radiates or not. let me know so I may use it or
discard it to satisfy the group. Since R.F.what ever his name is
intent on desception by suggesting that window mesh wires to keep
insects out are 0.5" apart in mimicing my findings there is no point
in responding to him anymore with his trash in the future. As for
religeon, you will make no friends by encouraging others to forsake
their religeous faith in favor of homosexuality.
tom
>
> Well that's the end of this thread!
Because you said so?
>Clark and his followers now appear
> to be moving towards accepting NEC and also that mesh will radiate
> according to the physics portion of his degree in literature( assuming
> he is following the teachings of physics that is extensively
> used in literature and shakesphere) with honors for showing he
> had no balls when dancing in mesh tights at his hide out! It would
> appear that the group is in disarray over whether Clark is to be
> followed with respect to R.F. having the same characteristics of D.C.
> current when applied to a mesh conductor. When you all make up your
> minds whether a mesh radiates or not. let me know so I may use it or
> discard it to satisfy the group. Since R.F.what ever his name is
> intent on desception by suggesting that window mesh wires to keep
> insects out are 0.5" apart in mimicing my findings there is no point
> in responding to him anymore with his trash in the future. As for
> religeon, you will make no friends by encouraging others to forsake
> their religeous faith in favor of homosexuality.
Art, you really need to get back to the clinic for your meds before they
send the men in the white coats for you again.
tom
K0TAR
Richard Clark
I still don't see any NEC files. Would posting them be gay - or
heretical?
tom
It would depend on the spacing.
tom
K0TAR
Art Unwin
Then tell me. Do you agree with Clark and others that RF applied to a
mesh will short out at the first square of the mesh or not?
This is for discussion of antennas by the so called experts to educate
those who enjoy the hobby. You say that you have extensive experience
with antennas! So share with others your opinion whether a mesh screen
will radiate or not , and move away from your nonsensical attacks on
others and share your extensive experiences which you always shy away
from. If you move away again from antennas to vent your internal
feelings the thread will die whether you like it or not, as others
will move away from such response postings. Sooner or later you will
have to verify your expertise with antennas instead of constantly
wielding the knife, instead of contributing to the newsgroup with
respect to antennas. You called me "sick" and I respond with say "you
are a female impersonator"
You then come back with another rabid comment and so on. Is that what
you want for the group? If so, there are some here who will probably
join you since they are natural followers. In no time you can then
join those that decry religion and thus you will be in your comfort
zone if that meets your needs.
Antennas or slander, where do you want to go?
A group of hams have declared that mesh will fuse and will not
radiate. This is contrary to NEC teachings so what shall we believe,
NEC or the opinions of this group?
christofire
"Art Unwin" <arthu...@gmail.com> wrote in message
news:855eb097-2dad-447d...@v25g2000yqk.googlegroups.com...
** New posting, not from the previous author Art Unwin (clear enough?). The
author of the previous post apparently forgot to sign his name.
Art, you must be applying EzNec, or whatever it is you use, beyond its
capabilities. As I wrote several days ago, if you believe an EM wave
travelling on a transmission line (in a normal transmission-line mode such
as a TEM wave) can propagate beyond a short circuit between the conductors
of the line then I think you are missing something rather important - like
Ohm's law!
Some clever antenna designs make use of a short across a line to reflect the
differential-mode wave (in order to improve the match) whilst allowing
propagation of a common-mode wave beyond it (in order to increase the
effective length of the driven element). However, it would be difficult to
apply this to a piece of mesh - lots of inter-node links would need to be
cut. At the end of the day, almost anything can be made to radiate,
inefficiently though.
** This post from chris...@btinternet.com , not Art Unwin (clear
enough?).
Chris
christofire
"christofire" <chris...@btinternet.com> wrote in message
news:fYmdnd6P2rohvGfX...@bt.com...
** additional posting from christofire@etc., not from Art Unwin.
I just wrote 'Art, you must be applying EzNec, or whatever it is you use,
beyond its capabilities' but it could be simply that you are
mis-interpreting the results it gives. Richard Fry's effort at
http://i62.photobucket.com/albums/h85/rfry-100/Arts_Mesh_Antenna.jpg
suggests a VSWR approaching infinity - what VSWR did your model give for a
shorted transmission line of small length?
** Chris (again)
JIMMIE
No such consensus that I am aware of . It could behave in many ways
depending on geometry, frequency, size. I have a slot antenna that
could be described as such. I doubt if anyone here would claim that it
will short or fuse.
Jimmie
JIMMIE
Alas are we here to praise or bury NEC.
Jimmie
tom
You misunderstood what they stated, but that's nothing new.
> This is for discussion of antennas by the so called experts to educate
> those who enjoy the hobby. You say that you have extensive experience
And you are an expert? I think not.
> with antennas! So share with others your opinion whether a mesh screen
> will radiate or not , and move away from your nonsensical attacks on
Sure it will radiate, like crap, which is what the link RF put up
showed. Or are you also ignorant and can't read text and a graph?
> others and share your extensive experiences which you always shy away
> from. If you move away again from antennas to vent your internal
> feelings the thread will die whether you like it or not, as others
> will move away from such response postings. Sooner or later you will
> have to verify your expertise with antennas instead of constantly
> wielding the knife, instead of contributing to the newsgroup with
> respect to antennas. You called me "sick" and I respond with say "you
> are a female impersonator"
> You then come back with another rabid comment and so on. Is that what
> you want for the group? If so, there are some here who will probably
> join you since they are natural followers. In no time you can then
> join those that decry religion and thus you will be in your comfort
> zone if that meets your needs.
> Antennas or slander, where do you want to go?
> A group of hams have declared that mesh will fuse and will not
> radiate.
No one said that. Show me a quote.
This is contrary to NEC teachings so what shall we believe,
> NEC or the opinions of this group?
I thought you said NEC was crap.
What do you believe?
I believe you need meds.
tom
K0TAR
Art Unwin
> "Art Unwin" <arthurun...@gmail.com> wrote in message
Well you started all this but never explained your position so Clark
entered the picture with his interpretation of physics which appeared
to match yours.
Ohms law is fairly short so explain your position.
>
> Some clever antenna designs make use of a short across a line to reflect the
> differential-mode wave (in order to improve the match) whilst allowing
> propagation of a common-mode wave beyond it (in order to increase the
> effective length of the driven element). However, it would be difficult to
> apply this to a piece of mesh - lots of inter-node links would need to be
> cut.
Yup you need a more expensive program to do it. Eznec wont do it.
You will need a lot of segments. Of course you can measure it if you
have a sample and a MFJ259b like I did.
At the end of the day, almost anything can be made to radiate,
> not very efficiently tho.
Hmm, mesh allows the displacement to be broken up into parts which
allows for the intersection of two fields to create radiation by
particle levitation where as your way you would disregard the enclosed
particles by the displacement current so you can state a wave floats
away for propagation
>Any thing can radiate
Very true unless, as Clark states, a direct short results and that is
stupid. But he likes to mislead others into agreeing with him. Then on
insults start and we are again at that point.
>
> ** This post from christof...@btinternet.com , not Art Unwin (clear
> enough?).
>
> Chris
tom
>
> Well you started all this but never explained your position so Clark
> entered the picture with his interpretation of physics which appeared
> to match yours.
> Ohms law is fairly short so explain your position.
Art, you've obviously forgotten that YOU started this thread.
Get meds, you need them.
tom
K0TAR
Art Unwin
> "christofire" <christof...@btinternet.com> wrote in message
>
> news:fYmdnd6P2rohvGfX...@bt.com...
>
>
>
>
>
> > "Art Unwin" <arthurun...@gmail.com> wrote in message
> > enough?).
>
> > Chris
>
> ** additional posting from christofire@etc., not from Art Unwin.
>
> I just wrote 'Art, you must be applying EzNec, or whatever it is you use,
> beyond its capabilities' but it could be simply that you are
> suggests a VSWR approaching infinity - what VSWR did your model give for a
> shorted transmission line of small length?
>
> ** Chris (again)
Look at my page ! I measured it! See for yourself.
Should I ignore actual measurements ?
Fri didn't show all the data used, but he DID falsify the distance
between wires which has a direct bearing on impedance/ VSWR ? Not only
that, we only have his word that he used a program with enough
segments to model the same sample that I measured.
As for my modeling I never did one for a shorted transmission line.
I can tell you, that I will model a ribbon style helix antenna as
shown on my page and I will present it for all to see. You may then
comment why it is in error per the groups interpretation. That is
basically a shorted ladder line which is being used as a radiator
which apparently you are looking for. The cross bars will simulate a
ladder line where it got wet which reduced the effect of the
insulation dependent on the frequency applied.This allows the
displacement current to deploy earlier than intended by the design
and thus radiate. Discuss with your physics friends or just rely on
Clark;'s antics.
Art Unwin
I don't know. I was comfortable with NEC until Clark stated it was
producing incorrect answers i.e. it shorts so it cannot radiate, It
seems that the group agrees with him.
Must I now throw my antenna programs away to abide by the majority of
the experts?
Art Unwin
Yes idiot. I started it after Clark made an observation and the group
agreed with him.
I am not willing as yet to discard NEC just on his say so.
Are you? Why?
Art Unwin
OK Tom
I called you an idiot in return last time.
This time I will ask if you ever perseuded your wife to
come back home after your last augument? Why is she refusing?
You sound lonely.
Are you and I going to take over this newsgroup from now on?
You insult and I insult in return?
What are the limits on the type of insults before the cannons come out?
Art Unwin
Heh. If you can't be bothered to read it in the first place
then you surely will not read a quote. Did you ever graduate from high
school?
What did you graduate from next? I know, you have never responded on
that to others.
Why did you beat your wife in the first place that made her leave?
Art Unwin
Jimmie
Have you plonked Clark?
orfus
orfus
Art Unwin
Hmmm. who is this?
I may do as you say, who ever you are. Welcome to the group of
arguement, you fit in well
Art Unwin
Am I ?
Richard Clark
>> Have you plonked Clark?
What a curious complement. I have "plonked" Art, and it has reduced
screen clutter other than that which survives quotation (fellows, you
really need to learn selective quoting - wading through his rambles
returns that tedium by proxy).
In the world of physics that goes to particles, photons, the weak
force, and so on, there is a branch that takes on "strange
attractors."
I wonder what force restrains Art from "plonking" me?
I happened upon a recent incident in Soccer that had a youtube
commemoration of a thrashing (those girls show more muscle than Art)
set to a song by Drowning Pool:
Let the bodies hit the floor
Let the bodies hit the floor
Let the bodies hit the floor
Let the bodies hit the floor Beaten why for
Can't take much more
One - Nothing wrong with me
Two - Nothing wrong with me
Three - Nothing wrong with me
Four - Nothing wrong with me
One - Something's got to give
Two - Something's got to give
Three - Something's got to give
Now
Let the bodies hit the floor
Push me again
This is the end
Kind of repetitive. Lots of anger. Cogent self analysis. More
repetition.
And it is rebellious.
Well, I don't expect any NEC file (damned if you do, damned if you
don't - had to keep the religion in it).
Richard Fry
> As for my modeling I never did one for a shorted transmission line.
Art, are you thinking that if you put a short circuit across the
output connector of your HF transmitter, it will not be affected -- as
the short is not located one wavelength or some other length from the
source?
If so, please invoke your self-stated spirit of experimentation by
doing so, and reporting back to us with the result.
For those not so adventurous, the link below leads to a NEC analysis
that should be of interest. Note that zero current flows past the
first short in the line.
Art - consider how the result of this NEC analysis affects your
concepts about a mesh antenna (no matter what the grid spacing).
http://i62.photobucket.com/albums/h85/rfry-100/Arts_Ladder.jpg
RF
Registered User
<arthu...@gmail.com> wrote:
>
>Then tell me. Do you agree with Clark and others that RF applied to a
>mesh will short out at the first square of the mesh or not?
The correct answer is maybe. The characteristics of the intersection
of any two wires in the mesh can be dynamically inconsistent. At any
time any junction might act as an insulator, a conductor or a
semiconductor.
It would be wise to understand the materials you're working with
before making any grand assumptions. If any two intersections in a
mesh can have different characteristics, any piece of "identical" mesh
will be different from its model. Such differences will make it
impossible to create reproducible results.
Cecil Moore
> For those not so adventurous, the link below leads to a NEC analysis
> that should be of interest. Note that zero current flows past the
> first short in the line.
How about the plumber's delight techniques used
in beam construction?
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com
Michael Coslo
> On Nov 10, 8:40 am, Michael Coslo <m...@psu.edu> wrote:
<snip>
>>
>> But the rest of you take notice, and quit hijacking Art's thread here to
>> talk about field day. I want to hear about how NEC has it all wrong!
>>
>> Sheesh!
>>
>> - 73 de Mike N3LI -
>
> Consensus of the group say RF applied to a mesh will short or fuse.
> NEC shows that it will not and that it will radiate.
> On my home page I did the same thing and got an SWR curve
> Therefore Art and NEC programs have got it all wrong.
> This probably means that a faraday shield will short also, but that
> needs a little more
> consensus from the group as it would destroy the shielding of the
> innards.
> Therefore the NEC programs must have it all wrong!
As a side note, last night I won my clubs "weird antenna" contest with a
2 meter vertical dipole made from Jello! (this is not kidding)
Top half was Orange Jello - with a little salt added, bottom half was
raspberry Jello and some salt.
Now on to the NEC issues. There is no doubt that in certain applications
or antennas that NEC will have some problems in calculation.
It is doing a service to the discipline to point out these special cases.
But that doesn't mean that NEC is invalidated because of those cases.
Just means some fine tuning is needed.
I don't get too excited about antennas until they are built. Simulations
are not the end product.
Art Unwin
> On Tue, 10 Nov 2009 18:09:34 -0800 (PST), Art Unwin
>
>
> >Then tell me. Do you agree with Clark and others that RF applied to a
> >mesh will short out at the first square of the mesh or not?
>
> The correct answer is maybe. The characteristics of the intersection
> of any two wires in the mesh can be dynamically inconsistent. At any
> time any junction might act as an insulator, a conductor or a
> semiconductor.
Yes that is correct, the same goes with any radiator or antenna
>
> It would be wise to understand the materials you're working with
> before making any grand assumptions. If any two intersections in a
> mesh can have different characteristics, any piece of "identical" mesh
> will be different from its model. Such differences will make it
> impossible to create reproducible results.
Well it wasn't a "grand assumption.) To remove the "maybees" that you
refer to you, use as a sample a stretched lath or a multi perforated
sheet of aluminum from the local hardware store
If you are uneasy about using mesh then weld the intersections using a
car battery set up.
or buy a welded shopping basket and play with that to duplicate
reports. Imponderables are always best removed before
experimenting. You can buy sample sheets of different types of mesh
with different types of materials, weave or otherwise on E Bay but as
always
mesh types have to be cleaned of coatings and less so for perforated
forms. The graphs pictured on my page were of these types and the
curves shown are on site measurements.
As always trust in computer programs but always verify.
Michael Coslo
> On Nov 10, 3:00 pm, Richard Fry <r...@adams.net> wrote:
>> On Nov 10, 10:16 am, Art Unwin <arthurun...@gmail.com> wrote:
>>
>>> Consensus of the group say RF applied to a mesh will short or fuse.
>>> NEC shows that it will not and that it will radiate.
>>
>> How much will your mesh antenna radiate, unless you have invented a
>> VERY heroic network to match it to typical transmission lines
>> (comments, please)?
>>
>> http://i62.photobucket.com/albums/h85/rfry-100/Arts_Mesh_Antenna.jpg
>>
>> RF
> Actual mesh used by Art
> Aluminum mesh, windows, insects
> Wire dia .011", mesh 18 by 16
> Per group analysis, wires will short.
Perhaps I should have read this before my previous post - You did build
an antenna? If so, my apologies!
Michael Coslo
Who is this group you speak of, and where and how do they decide things?