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What do you mostly want to read about when it comes to antennas?
  Posted: Feb 11, 2010   (1564 votes, 29 comments) by K0FF

  Computer Modeling results, graphs and charts...
  Mathematical analysis...
  Practical application/experiences...
  How to build with common materials...
  Clever mechanical "tricks"
  All of the above!
    (1564 votes, 29 comments)

Survey Results
Computer Modeling results, graphs and charts... 2% (31)
Mathematical analysis... 1% (10)
Practical application/experiences... 31% (490)
How to build with common materials... 27% (423)
Clever mechanical "tricks" 3% (40)
All of the above! 36% (570)

Survey Comments
HAMS are inventors
I like to see ANY research and experimentation on antennas.
Hams are a HUGE untapped resource of inventors and engineers.
The next quantum leap in antennas will likely come from the ham community.
And I wouldn't be surprised if it comes from a EHAM forum!

Posted by N8EKT on March 13, 2010

subjective results
Too often, people will talk about an antenna and act as though a QSO with a far-flung operator will prove the worthiness of a particular design or its implementation. This not the way to go about it - propagation, and other factors, lead to widely varying results with the same antenna design. "Miracle" antennas, which seem to defy commonly accepted physics, should be treated with skepticism. Good antenna articles come from good antenna design, with good, scientific measurements of characteristics, as well as analysis by antenna modelling programs. Explaining WHY a particular antenna is worthy of note is required.

Posted by N1YRK on March 10, 2010

Antennas are fun
I built a all band dipole for 160 to 10 using two 130 foot dipole pieces center fed with 78' of 450 ladder line going to a MFJ 912 4 to 1 balun and down to a Palstar 1500 tuner using 20 feet of RG 213. Apex is about 65 feet, sides 30. I use on a TS950sd with a auto tuner that tunes every band using the Palstar straight through. Buddy of mine and I laugh at the mismatches and coin it the WAG antenna which is a wild a-s guess that just got lucky. At 71 I can still get the wires to hum and have worked many dx and locals all with good signal reports with 150 watts. So If you think your to dum to build antennas think of the old gas passer in Georgia that is still having fun.Oh I'm on a granute structure so the ground is null. Jim W4EPA

Posted by W4EPA on March 9, 2010

Antenna Modeling
Hi Dan,

Many thanks for that tip on 4nec2---my curiousity & interest are DEFINITELY picqued...!

A mile long Vee beam to Asia, you say...?! Now THAT'S the sorta stuff that really gets my adrenalen flowing! Hi Hi. Even Bill Orr would NEVER have actually PHYSICALLY tried to string-up something like THAT, Hi Hi (and quite frankly, neither would I!)...

Speaking of Topband receiving antennas, I'm continually amazed at the performance of the K9AY loop here: until I terminated it at its south end, my (then) bi-directional 1500' Beverage would never equal the performance of my north K9AY in copying "JA" stations. The K9AY was always just so very much quieter than the longwire...and that made all the difference.

I wish I could have terminated the NORTH end of the Beverage for a comparison vis-a-vis the K9AY toward Japan, but property constraints here prevent me from doing so (sigh!).

Keep up the good work Dan, & we'll see you in the pile-ups on 160...

~73!~ de Eddy VE3CUI - VE3XZ

Posted by VE3CUI on March 2, 2010

"Hardware or custom parts are a
problem here. there is a need for the custom
plastic parts for antennas. "

You need a RepRap:

http://upload.wikimedia.org/wikipedia/commons/0/06/RepRap_v2_Mendel.jpg

Posted by N3OX on March 2, 2010

Yeah N6LF's work is a great example of how to do a controlled experiment to find out exactly what you want to know, and the comparison with models is really fascinating.

" I must say, I’ve thoroughly enjoyed our recent exchanges here, and have come to the conclusion that you & I actually share more in common than was initially thought possible…!"

Me too, and I'm glad we got there. I think it's important for the people who really like models to consider the opposite viewpoint and what it is that actually worries people...

Sometimes it's difficult to get past one's own idea that the fact that models work and are based on Maxwell's equations is enough of a counter-argument, because others don't really have any idea if N3OX has any idea what he's doing.

There *are* people who run of over-idealized useless models or models that have numerical problems or whatever. The modeler has to ask the right question to get the right answer, and some people don't recognize how that objection is important.

If you want a cheaper modeling program, 4nec2 is free. I haven't used it yet but will probably add it to my arsenal soon because it has an optimizer.

And if you don't want to model anything, ever, that's fine too. It was a fine cool springish weekend and I spent the whole time outside putting my 20/17 Moxon back up with some mechanical and grounding improvements, new rotor, fresh coat of paint on the plastic bits. Fresh air, sore muscles, and the sense of accomplishment with a job finished well are absolutely important to me.

But every once and a while you might find a modeling super-genius who doesn't like that (or, you never know, maybe CAN'T do that anymore) ... and they may have some sweet ideas.

Models are also great for ridiculous what-if scenarios... you have the room for a mile long V-beam on Asia? Is it worth it?

And what about really stupid antennas that no one should ever build:

http://www.eham.net/articles/20174

:-)

73 Eddy,
GL with the rest of the TB season. Got the flag fixed last night and I'm ready to snag Willi on SV5 for a new one...

Posted by N3OX on March 2, 2010

thanks eham
Almost forgot. i have a diamond style fiberglas
housing , the remnants of the dual band vhf uhf
vertical and never liked the shunt feed design
.Looking for ideas to make a5/8 vhf uhf design
that will work in the fiberglass tube

Posted by WM9V on March 2, 2010

thanks for gap repair pics
Ive got all kinds of projects. klh Oscars for
432 and vhf that are very old designs,
antiques in fact. Currently there are dozens
of antennas here that need design changes or
repair. A 2 foot log periodic with 40
elements that needs a feedpoint and a balun
on the back. I have a gap challenger that was
beat up in a storm and replaced all the
tuning sections and refastened the sections.
Thank you for the article on the tuning caps
on the top. That filled in the missing blanks
with pictures! Hardware or custom parts are a
problem here. there is a need for the custom
plastic parts for antennas. we can all get
standard tubing and for the most part
recreate most commercial products. broken
plastic element bracing and metal element to
boom masts are always a focus for
inventiveness and homebrewing. We are also
frustrated by uhf and vhf designs of
eggbeaters and similar patterned antennas.
Also rebuilding a dropped hygain jr and
subing the crappy match for that product.
A huge hit here has been the intro of the
hazer ,which recently got a used rotor
rebuild and the ham4 box mod to match meter
tracking.
Very interested in home brew el al rotor
ideas as well as usb rotor interfaces. Line
powered home brew antenna preamps are needed
too.
A real fav anntenna is a long boom klh vhf
wide space beam with log periodic fed
elements. This antenna is larger but the log
feed system has been used on shorter booms
with two elements. Pics are hard to come by
of these antennas in detail. Wire antennas
are always a huge hit as are feedlines. We
actually got ahold of a bunch of 1 5/8
aluminum hardline and going thru the
connectors to see how they can be adapted to
pl . Too much to list but plenty to do .Put
your pics and ideas on; we would love to see
them. We have already seen what the rest of
the world is doing and we would like to see
your input.

Posted by WM9V on March 2, 2010

Antenna Modeling
Hi Again Dan,

Isn’t it interesting how two initially opposing viewpoints seem to find common ground as the frequency of communication increases…? I must say, I’ve thoroughly enjoyed our recent exchanges here, and have come to the conclusion that you & I actually share more in common than was initially thought possible…!

I confess to my once having come “…this close” to purchasing antenna modeling software, from an ad seen in QST magazine. To this day, however, I can’t say for certain if I declined its acquisition because I considered the price to be too exorbitant for my fixed retiree’s income, or if I feared the possibility of my succumbing to the temptation of having more fun modeling antennas, than actually dragging myself hither & yon outdoors and actually building them…!

No matter: I passed at that time, but have since had to endure a small, nagging little voice from deep within me constantly saying, “One of these days…! One of these days…!” Hi Hi.

Perhaps the best contemporary antenna article that I’ve seen yet---one that very effectively marries antenna modeling with “A” vs. “B” comparisons with “real world” hands-on results---was a series published in QEX by Rudy (N6LF). Have you read them, Dan? If not, they may be viewed by clicking onto:

http://www.antennasbyn6lf.com/2009/12/series-of-qex-articles-on-ground-system-experiments.html

The author has effectively “raised the bar” in terms of antenna article writing with these seven pieces, IMHO…

~73!~ de Eddy VE3CUI – VE3XZ

Posted by VE3CUI on March 2, 2010

"These Amateurs had a gift in being able to combine the technical facets of an article, with end-result "real world" descriptions...they made you actually WANT to go out and build whatever it was that they were proposing would make your station better.."

That's very important. If no one wants to build the antenna you praised in an article, you haven't done your job as an article writer.

But a good design is a good design even if the author didn't build it. L.B. Cebik is a good example of the value of this. He *did* build a lot of antennas, and he put thought into actually how to build things.

But he also put a whole lot of work into pure modeling with good results. And I've built some Cebik designs straight up and been very happy, like my 12 element UHF yagi (which both model and measurement agree has 6dB gain over my 4 element UHF yagi).

I built a Moxon rectangle for 15m the other day. I used AC6LA's Moxgen program which is based on Cebik's formulas from mathematical function fits to model results. I built it to good accuracy (+/- a few mm) and put it up. With no tweaking, it's got good SWR and better than 20dB F/B as measured to another antenna on my property.

http://n3ox.net/file/15_moxon_measurement.jpg

Of course, the real world result has a lot of effects that a *simple* model wouldn't show, but a lot of them are likely pure measurement error... my rotator doesn't rotate constant speed, my reference antenna is not the best type for this measurement, and both of my antennas are moving in the breeze because they're spindly wire and fiberglass types.

"Am I really & truly the ONLY guy left in the world who---after slogging through some long technical treatise, replete with charts, graphs, & tables---wants to see a concluding paragraph that begins with the words, "Now here's what happened when I fired-up the station with the new antenna connected...""

No, you're not the only one, but I'm not there with you. I don't really care about that in terms of picking antennas. I like a good success story for what it is, but I personally won't put up antennas here based only on someone else's **on-air** results like what they worked and what pileups they broke. What I care about is how the antenna will work when I put it up at my station, not really how it worked on-air for someone else.

In my opinion, all the information about how an antenna is likely to work at my station compared to what I've already got is contained in hard numbers. I already know how my antennas work for me on-air. I already know what their strengths and weaknesses seem to be, what DX I can work and what I have trouble with. When I'm looking for a new antenna, I want to have a reasonable expectation that it will work X dB better.

I don't really care if that knowledge of the objective performance comes from model or measurement provided that both are done well. Articles with both are great, probably the best. Articles with neither don't help *me* make decisions.

I've busted enough pileups with 100W to an apartment antenna to appreciate how little a 10dB on-air disadvantage matters sometimes, and had stations CQ in my face enough times to recognize that a few dB advantage REALLY matters other times.

And I also just don't have enough space to enjoy putting up and testing antennas that have a good chance of not actually being better than what I have just for the sake of pure experimenting.

My sunny outlook on models comes from the success I've had in using them as a tool to build my current station despite the fact that it's kind of hard to put antennas up here. I can't just sling stuff into trees all day or haul something else up the tower because I don't have trees or a tower. I can't try big receiving antennas for 160m because I can just barely fit a flag.

"To-day's stuff seems to inspire guys to want out to go out and simply MODEL something that looks better on paper."

Yeah, I see what you're saying. What you want to know is "are they better in real life too?"

And that is an important question. I can imagine someone having the same sort of feeling about models that I have about articles with no objective performance predictions, basically, it's nice for them, but I don't think I'm going to spend a weekend finding out for myself that it doesn't work better than what I've got.

But what I've found around here is that I don't have to do much tweaking if I model something before I build it. So I'm really fine with someone who has a good idea in a model and writes it up without trying it. I find that enough cause to try it myself. I understand and respect that not everyone feels that way, but I don't agree with them.

73
Dan




Posted by N3OX on March 1, 2010

Antenna Models
Hi Dan (N3QX),

Please don't get me wrong: it's not that I dislike, or distrust, computerized antenna modelling---far from it! I agree with you that they are a VERY useful & powerful tool in the pursuit of our mutual happiness, i.e. the propagation of ever-more effective "sky hooks"!

What I VEHEMENTLY object to, however, is the absence in antenna articles of late of the "...good ol' Elmer"-type factor in the authors' write-ups: "good ol' Elmer" seems to have been completely eclipsed by "go-getter Poindexter", it seems to me.

Techno-pieces are great, but let's face it: how many Hams to-day live & breath only to model the last "nth" of a decibel out of some conjectured design? Remember, a whole generation of Hams to-day was weaned on the writings of guys like Bill Orr, and Lew McCoy. These Amateurs had a gift in being able to combine the technical facets of an article, with end-result "real world" descriptions...they made you actually WANT to go out and build whatever it was that they were proposing would make your station better...

To-day's stuff seems to inspire guys to want out to go out and simply MODEL something that looks better on paper.

Just look at the results of the survey so far: is the overall collective reaction of "the great unwashed" one that is screaming for more mathematical & computerized models...? Hardly.

Again, computerized modelling definitely has a place in our Ham world---but this should be tempered with---and here I go again (sorry!)---"real world" results.

Am I really & truly the ONLY guy left in the world who---after slogging through some long technical treatise, replete with charts, graphs, & tables---wants to see a concluding paragraph that begins with the words, "Now here's what happened when I fired-up the station with the new antenna connected..."

My God, I hope not, because if it's so, then we'd better launch ourselves into nearby fields & meadows come summer, & explain to bumblebees why it's scientifically impossible for them to fly...

~73!~ de Eddy VE3CUI - VE3XZ

Posted by VE3CUI on March 1, 2010

"I don't know what YOU'D call that, but the words arrogant, elitist, and intolerant spring forth in my mind..."

You know Eddy, I see where you're coming from, if you think I'm bashing a good work ethic and if you think that I think only the computer nerds are smart enough to do anything with antennas or whatever.

But that's not what I think.

I said what I said because I'm sick of hearing that real world tests are good and modeling and theory are bad.

It doesn't work that way.

There are good experiments and bad experiments, just as there are good models and bad models, and there's correct theory and wrong theory.

You don't like models. You don't want to read about them. Why? They actually work really, really well in many cases.

So does slogging through the bog a dozen times to adjust your Beverage termination and making fifty trips up and down the tower to tweak your yagi's F/B.

But the fact that the "real world radio" involves more perspiration doesn't *necessarily* make the results better. It doesn't make them WORSE either. I'm not saying that. I'm just saying that models work too, and may, in some cases, actually have less error than measurements and give a better picture of how a couple antennas might compare.

I see a lot of baseless mistrust of computer models. I see a lot of people who seem to think the answers they give are wrong. I see people wishing that there wasn't so much "theory" and whatever. What I don't see is a big pile of experiments that *show* that good models are wrong.

I have absolutely no disrespect for people who use all their ham radio antenna development time trying new things in the real world instead of on the computer.

But saying that models are not "real life radio," calling into question whether hams who make heavy use of models actually build anything and test their designs?

I don't like that.

73
Dan

Posted by N3OX on February 28, 2010

KJ4EED says:

"This is a Sophomoric conclusion. You assume too much about people. People are not stupid.
"

I didn't say everyone did that. But some people *certainly* do that, and it seems to me that it's not uncommon. Anyone who's ever said " it works so much better than the antenna I used to have up" has big error bars regarding that antenna's objective performance.

If all the hams you interact with are fond of controlled quantitative experimental tests of antennas, please shoot me an email and tell me when you guys are on the air because I'd like to hang out with you.

73
Dan

Posted by N3OX on February 28, 2010

Antenna Modelling
Wow, Dan (N2QX)...!

I guess in your world, then, OM Thomas Edison had it all wrong when he said that inventive genius was "...90% perspiration, and only 10% inspiration".

From your perspective, he SHOULD have simply declared, "Let's plug the numbers into the model & see what comes up."

I don't know what YOU'D call that, but the words arrogant, elitist, and intolerant spring forth in my mind...

~73!~ de Eddy VE3CUI - VE3XZ

Posted by VE3CUI on February 28, 2010

Some antennas that FIT and WORK
"I like to see antenna projects that will fit in my space, not something for the ranchers, like how to build a 160 meter rotatable Beveridge"

http://www.eham.net/articles/16044

http://www.eham.net/articles/14332

http://www.eham.net/articles/1607

http://www.eham.net/articles/1400

http://www.eham.net/articles/1248

K0FF

Posted by K0FF on February 28, 2010


"You've got the people who NEVER do anything other than on-air tests without both antennas up at the same time, who don't recognize that huge variations in conditions make their results useless to anyone else. They try to measure 3dB differences with signals that slew around 30dB."

This is a Sophomoric conclusion. You assume too much about people. People are not stupid.

Posted by KJ4EED on February 28, 2010

"I like to see antenna projects that will fit in my space, not something for the ranchers, like how to build a 160 meter rotatable Beveridge"

http://www.n4is.com/wf/NEW_WF.html

Posted by N3OX on February 27, 2010

"I don't doubt their tech-savviness with a computer, but I have to wonder how many of these Hams have ever actually strung wires through thickets & bogs in sub-zero weather,"

So you have to haze yourself to actually know something about antennas? :-)

Physical difficulty doesn't *actually* make antennas work better... :-) Building antennas does make you understand more about antennas... maybe that's what you're getting at.

I think there's kind of this running assumption that people who often answer antenna questions with model results are egghead computer nerds who never solder wire or put hacksaw to tubing or get dirty and wet putting up their Beverages. You're not the only one to express this sentiment.

But I think it's kind of off the mark. Why would someone care so deeply about antennas if they didn't build them?

I think they like models because they've found them to be reliable and useful in "real life"

Making a model that actually represents the antenna in the real world requires care and thought and creativity and probably, for most folks, a healthy dose of solder smoke and pop rivets, dirty fingernails and sore muscles. But it doesn't absolutely require building everything you ever might think to write an article on once you've got the modeling down.

That's not to say you should trust everyone who includes some model plot along with their antenna article. Some people do know what they're doing, some don't. Some people put a plot up that's really generated for a situation nothing like what they're writing about, others will likely be accurate to a fraction of a dB.

"There's "cyber radio", and then there's "real life radio". We're getting far too much of the former of late, & far too little of the latter, IMHO!
"

So do it. Gimme a pattern plot of one of your receiving antennas.

The problem I see with "real life radio" is that just as there are bad modelers who misuse computer tools, there are bad experimentalists too.

You've got the experiments where people try two different antennas in a semi-controlled way and find that one is vastly better in a way that's not really possible.

But instead of going back and finding the experimental error, the thing they didn't control for, or whatever, they come up with an explanation for they're result that's not consistent with the physics behind antennas.

You've got the people who NEVER do anything other than on-air tests without both antennas up at the same time, who don't recognize that huge variations in conditions make their results useless to anyone else. They try to measure 3dB differences with signals that slew around 30dB.

It's very hard and labor intensive to do controlled experimental work that shows something really useful and can be trusted as capturing the general trend of things. N6LF's radial experiments are a good example of this.

A lot of people try stuff and then overstep the conclusions, sometimes into the realm of physical impossibility. I think that kind of result is unfortunate, because it sticks well in peoples' minds, because of the "real life" aspect. Whatever happened, happened.. even if what happened is totally different from the explanation offered by the experimenter and is totally irreproducible on the basis of that explanation. I can think of popular antenna construction websites whose content seems to be based almost entirely on deeply flawed experiments.

Problems with antenna articles don't divide neatly into "cyber antenna" vs. "real life antenna," and my opinion is that since hams implicitly trust "real life" results so much more, they can have worse effects on people's understanding of how things work.

73
Dan

Posted by N3OX on February 27, 2010

Big big big
I like to see antenna projects that will fit in my space, not something for the ranchers, like how to build a 160 meter rotatable Beveridge or the 5/8 wave 80 meter vertical with full efficiency radial system.

Posted by W8AAZ on February 27, 2010

Antenna Modelling
Have you ever seen the old movie, "WILL SUCCESS SPOIL ROCK HUNTER?"

It starred (I believe) Tony Randall & Rock Hudson. This flick is a comedy about a self-styled "expert" fisherman who wrote a book on the subject---but had never so much as caught a fish in his life!

The film reminds me a LOT of to-day's antenna wannabe "ghurus" whose articles in QST, etc. are LONG on computer modelling results & plots, but oh-so-thin on actual hands-on real-world results.

I don't doubt their tech-savviness with a computer, but I have to wonder how many of these Hams have ever actually strung wires through thickets & bogs in sub-zero weather, & how many did all of their research comfortably seated before a computer, just as I'm doing right now...

There's "cyber radio", and then there's "real life radio". We're getting far too much of the former of late, & far too little of the latter, IMHO!

~73!~ de Eddy VE3CUI - VE#XZ

Posted by VE3CUI on February 27, 2010

Theory?
I enjoy antenna articles so much that they are the main reason I visit e-ham. However, I find myself unable to correctly answer the survey. Maybe if there were a "antenna theory", or "none of the above" choice....

Posted by KI8JD on February 22, 2010

antenne
Quelq'un connaitcette antenne?Megabeam antenna 4104 de SHAKESPEARE 4 element pour le 11m et 10m surtout le gamma macht.

Posted by VE2AVJ on February 22, 2010

Model This
N3OX sadid: "I don't know why my comments are in one column
of two column format. Sorry :-)
Posted by N3OX on February 14, 2010"

I'll model that and get back to you Dan.

Geo>K0FF

Posted by K0FF on February 16, 2010

Antenna Construction - a technical hands-on for the average ham
Microprocessors, software, surface mount components are all wonderful elements in ham radio. Unfortunately, they are somewhat out of reach for many hams. Antennas are the interface to the universe are arguably the most important element of any station and open to the do-it-yourselfer.

Posted by NJ2X on February 14, 2010

I don't know why my comments are in one column
of two column format. Sorry :-)

Posted by N3OX on February 14, 2010

I wanna see more articles on how the home
builder can really measure the performance of
their antenna, and on real comparison
measurements in dB that others have done
along with the method they used to do that.

It's hard to do that and it takes up a lot of
time, so the data from articles like that, if
done right, are a real service. And it's
hard sometimes to figure out the cheap test
gear and methods that might allow you to
*really* know how your antenna is working.
It's great when someone writes an article
based on lab-grade test gear, but that
doesn't help other people answer their own
questions.

I want to see the article where someone walks
you through the construction of a cheap 2m
yagi and then walks you through how to take
a pattern to your computer

In the spirit of "all of the above," I'd also
like there to be a comparison with a model,
because I think some are very dismissive of
models even in those cases where they're very
likely to be in very good agreement with the
actual antenna in question. Something like a
VHF yagi high above earth with uniform
diameter rod elements and insulating boom,
all constructed to the nearest millimeter
should really show a fine pattern if
carefully measured with G4HFQ's polar plot
and a steady signal source:

http://www.g4hfq.co.uk/

That kind of article could have information
on how to get a cheap, stable signal source
and what kind of antenna it should have for
testing. Furthermore, it could discuss the
departure between the model and measurement,
something that's a very interesting place to
look.

- - - - - - -

I also would like to see more "practical
design" articles... that is, easy ways to
DESIGN an antenna that does what you want it
to. It's great when someone writes an
article like : "here's how to build a 20m/15m
trap vertical," but if a prospective builder
would rather have a 30m/20m or 40m/30m
vertical, maybe they have to look elsewhere.
If they want to switch coils and caps to
something closer to what they have in their
junkbox, a good "design" article could let
them do that in a way that a construction
article cannot.

Many construction articles, even if they give
a lot of options, have to be exactly
duplicated. There are a lot of nice free
software tools and good online resources that
can really help with antenna design. There
are a lot of online "resources" that can
really hurt too, so something that sorts
those out is great.

No article will ever replace learning by
doing, but I think we could write some
articles that show what's possible in
designing with model and software and
whatever, and then checking to see if that's
what happens in real life, and if it departs,
why does it do that?

How big are the discrepancies in dB, and what
are some hypotheses for why that happened?
Can you rule out some of those things with
further testing?

I've found design with model and software to
be very useful. I have a pretty cramped
space and in some cases, it's really tough
and frustrating to take an antenna up and
down sixteen times to tweak it so it works.
I still sometimes have to tweak things, but
my time spent tweaking has largely been
replaced by time spent designing.

This isn't necessarily a positive thing all
the time. If I had a giant yard with a tower
and didn't have to squeeze things in... if I
didn't have to worry about breaking one
working antenna by working on another one...
I'd rather be out in the fresh air taking
antennas up and down and fiddling with them.

But as it is, sketching it out on paper and
designing it electrically in models has
allowed me to put up some antennas that work
really well that I never would have been able
to practically construct in a completely
experimental way.

73
Dan

Posted by N3OX on February 14, 2010

Antennas - What?
What do you mostly want to read about when it comes to antennas?
The best answer is "Practical application/experiences."
Computer modeling .... etc? Anyone can get their own program and do their own modeling. This is modeling, It is not antenna building and use.
Mathematical analysis? If I were teaching, maybe. If I were on the job, maybe. When I want to get on the air, forget about it.
How to build with common materials? Anyone knows how to build. I want to know what to build. This choice does not get to the real issue.
Clever mechanical tricks? This misses the point, too! Save it for the magicians.
A ham should be most interested in the down to earth practical stuff foremost. Don't try to drive my position to an extreme. I do not mean simplistic stuff, nor exclusively non-mathematical stuff, nor reactionary antique stuff. I do mean stuff I can use here, now, and with some practical certainty and advantage. I do not mean high blown theory or folklore. With antenna information there is too much puffery.

Posted by AI2IA on February 13, 2010

Thank You
Hats off, and thank you, to K0FF, and others, for taking the time to share their antenna work with the Amateur community. As I always ask in a QSO; "what kinda toys are you using?" God Bless and 73...Jerry / N5JFJ

Posted by NE5C on February 12, 2010

I like antenna experimenting
I like to read about all sorts of antennas. Of course performance matters, but unique designs created to fill a niche are also interesting.

And sometimes it is also fun to see some of the odd ball things a ham can actually make a QSO on!


73
Dan
--
Amateur Radio Emergency Service, Clark County Indiana. EM78el
K9ZF /R no budget Rover ***QRP-l #1269 Check out the Rover Resource Page at:
<http://www.qsl.net/n9rla> List Administrator for: InHam+grid-loc+ham-books
Ask me how to join the Indiana Ham Mailing list!

Posted by K9ZF on February 12, 2010

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