UGH! Fire Hot!

INTRODUCTION
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xperimenting! Can you imagine the surprise of the first caveperson who stuck a hand into the fire after its discovery? Also, without instant wide-world cave-web communications, that experience could not be shared with other cave people who must have tried the same experiment with the same burning result.

By now, many may have noticed at the top of my monthly column, I have been taking the liberty of inserting a quotation from some of the great thinkers from our past. No lectures intended, but maybe a little philosophical. The quote I select for the month is usually one that fits the underlying theme in my mind at the moment I start to write this column. It is the very first thing I do at the top of a blank sheet and I have found they give me a little nudge and inspiration for what may follow in my column. Your indulgence with my choice of the month is appreciated.

As I scan some of the quotes, I find I don’t have to think about it—one simply strikes a note of harmony with me and that’s it! They may not do much for the reader at the time and one may disagree with the interpretation of the chosen quote, but I hope what I say below the quote is of use—even though you may disagree and argue in opposition—now, see why I picked the “Argument” quote? It is so applicable for our experimenters and those who would critique the outcome!

I suppose some who like to only do computer models could simulate the affects of sticking one’s hand in the fire, but sooner or later someone will have to actually do it to provide absolute proof that it would burn! The same applies to antennas and such.

PASCAL IS BACK
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Pascal Veeckmans, ON4CFC is an active member of the GARDS and was a regular contributor of articles to antenneX in past years. However, Pascal is employed by the Belgian army and is a member of the BAFARA Belgian Air Force Amateur Radio Association. So, it was not surprising that he was called to duty in Afghanistan where he served in a military unit guarding the airport of Kabul. This of course curtailed his activities at antenneX for a while.

Having returned from Afghanistan, Pascal is back at the hobby he loves, building antennas and related devices. His workmanship on his projects is nothing short of astounding as well as being clever in design. Just take a look at this beauty that is the subject of his article this month, entitled "A Home Brew CW Paddle." Indeed, he uses what he builds. He got his first license in 1996 and passed the Morse code in 1997. That earned him the call sign ON4CFC. Pascal can be heard frequently on the HF band. We are glad to welcome Pascal back to the fold. Pascal was born on January 13, 1965 in Tienen Belgium.

Also, Kudos go out to Dr. Jef Verborgt, a fellow Belgian now living in Florida, USA. Jef has been very helpful to Pascal, antenneX and our readers by acting as the translator for Pascal's articles originally written in his native language. Jef's articles also can be found in the archives of antenneX -- and is a member of the GARDS.

Jef Verborgt was born in 1944 in Belgium and was saved from a certain early death by meningitis by the American soldiers having the first penicillin -- for which he remains grateful. He went on to obtain a Ph.D. degree in Polymer Chemistry in 1970 at Louvain Belgium followed by a postdoctoral Fellowship with Dr. C.S. Marvel at the University of Tucson, Arizona. Jef was Director of Research for Sigma Coatings for 15 years after which he became Director of the International Business Operations for Marine and Protective Coatings. Jef further held the position as President of Sigma Coatings USA in New Orleans, Louisiana.

Jef is currently employed as a consultant/contractor at the Navy Research Laboratories in Washington DC where he is developing novel solvent free fast curing resin and coating systems.

A PORTABLE HF TRANSMITTING LOOP
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We have a new contributor this month in an article "Portable HF Transmitting Loop Antenna" by David B. Thomas, N5IZU. The picture here shows David operating "while on the go."

David says while HF antennas are not normally known for their small size, magnetic loops can offer quite respectable performance, at the cost of some efficiency and extremely narrow bandwidth. The tunable magnetic loop antenna shown here is David's contribution this month to the well-established art of amateur loop making. It is small and light enough to carry while operating; it disassembles into small but rugged pieces that fit easily in a backpack or gym bag and it can be tuned from 14 MHz to 30 MHz.

AN ANNUAL REPORT—Of Sorts
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That is the title of the editorial this month written by L.B. Cebik, Technical Editor for antenneX for the past three years and monthly columnist and feature article contributor for the past seven years. Although I won’t pre-empt LB’s article by quoting excerpts, he does make reference in general about the PC screen resolution being used by our readers today versus just a few years ago when it was the old 640x480. In fact, our articles were optimized to fit that screen size until a couple of years ago when our server technology was able to determine the screen sizes used by the readers during their stay at our web site and convey those useful statistics to guide us more accurately.

Based on such information a year+ ago, we changed our targeted screen size for the 800x600 pixel resolution on average because those stats showed us that 50+% of our online readers were using that size screen and only 5% or less used the old 640x480.

Now, only one year later, those stats show the resolution for 800x600 has dropped dramatically to less than 24% of the readers in favor of the 1024x768 that now represents almost 55% of the readers (see Table 1). Indeed, the Internet technology is moving fast as a result of broadband speeds, more powerful PCs and much larger and sharper monitors. The old 640x480 has completely disappeared from our major stats as they have dropped down into the “Others” category numbers in Table 1. These are very useful stats as we try to optimize our article presentations to best fit the users and the trends that are evolving.

My own most sincere personal thanks goes out to LB for his steady support throughout the many years since our paths met in early 1997. We are all lucky to share his contributions and I’m glad antenneX is able to provide his learned writings to even some of the most remote regions of the world. LB is one of the most kind and generous people I know and I’m lucky to be able to call him a true friend.

OTHER READER STATS
While on the subject of the reader stats, I can share a bit more information direct from our computer logs that may surprise some. At least the data will tell you where your PC software stacks up compared to the rest of the world that visits antenneX. Below are some stats gathered from the past week or so, which is only partial at best since antenneX is spread over 4 servers. They are a good representative sample however.

It is noted in Table 1 that "Windows 2000" runs on only 15.6% of your machines, versus the leader XP at 60%. On my own personal workstation, I use the Windows 2000 Pro. I would consider moving on to XP, but the fact that my Win2K install has been on my machine since original purchase/install right after its release years ago, argues against any change. Five years of stability and reliability reminds me that "if it ain't broke, don't fix it." Plus, it still runs most of my DOS batch files.

In all of the years since I started using the very first version of Windows in 1988 (which I fondly refer to as a "cartoon" by today's Windows' standard), this Win2K (NT5.0) version is refreshing. With Win98, I found it necessary to do a fresh install about every 4-6 months to regain some stability. Not complaining, just was part of computer life, but this is the first time in all those years I have not pounced on the latest version at moment of release. Another case of argument.

There are many more stats helpful to us on the server side, but the ones above should be enough to be most interesting for the reader side of the stats. For those loyal to Netscape, take note of its plunge like a lead balloon over the past few years. I used to keep a copy on my machine, but removed it long ago because of so many bugs that had crept in plus features it could not "see" on a web site like ours. It was our practice to optimize for both MSIE & Netscape when Netscape was still running neck and neck with MSIE.

The NS loyalist need not be offended by my observations about that particular browser. Personally, I don't care what the browser is called or who makes it. My concern is only that it be compatible with my needs and well-supported. Software cannot remain static and survive for long in such a fast-moving industry.

Those still using the really old versions of the Operating Systems and Browsers are encouraged to consider updating if you desire things to operate smoothly—and to make use of everything a web site has to offer. And make sure to enable things needed to operate the basics and avoid frustrations. If a web site uses JavaScript, then your browser better have it enabled. If you want your browser to remember your various logins, make sure to have "cookies" enabled.

BTW: The "browser" in the Table 3 called "EmailSiphon" is really not a browser, but a utility that does what its name implies—tries to siphon off or harvest email addresses from web sites. Our servers have alarms to alert us when one lands on the site and they are stopped and locked out. If you wonder where some spammer got your email address, this is just one of the ways.

We find such stats of invaluable help to us in the design and development of our web pages to follow the trends as may be dictated from time to time. On the other side of the coin though, it should be remembered that when one chooses a browser or operating system, etc., one should choose the those that has the proper tools to operate within the desired web sites. In other words, don't turn off JavaScript and then wonder why things don't work right. When in Rome.....!!

FORGOT OR LOST PASSWORDS?
Over the past few months, we have been busy automating some of our more time-consuming routine jobs that will make things easier at antenneX for our readers and ourselves as well, plus enhance our site efficiency.

One such job is that of helping those who have either lost or misplaced their password to the reading rooms. Throughout each month, but especially right after the publication of a new issue of antenneX, we receive many requests for help with passwords. There is usually some delay in replying to such requests because, heretofore, it has been a manual process.

Not anymore! We are pleased to finally provide this service as an automatic process with immediate response. We have placed convenient links on the login pages and the FAQ for your future use should it be needed. In the meantime, if you want to see the new request page, just go here: http://www.antennex.com/getpwd.htm

If your user name is an active email address, you would choose "Method 1 - FAST" to retrieve your password.

That depends though on whether your user name is still an active email address. I know for a fact that some of the email user names being used after several years are now stale. Moreover, a few user names are not email addresses at all and of course will not work with the automatic system because the password info must to be emailed to the user's active email address and must match the database to be found. If your email user name is not active, then the reply will bounce back and not be delivered to you.

Thus, if your present user name is NOT an active email address, you would need to choose: "Method 2 - SLOW" to retrieve your password.

It is "slow" because it still requires manual intervention to locate you from the databases. This method #2 will take you to another form to fill in the required info for this purpose so we can find you. Note, it will ask for an "Active E-Mail Address" which we will use and take the opportunity to update your user name in the database so that you can enjoy the use of the "Method 1 - FAST" next time you need help on this.

With the publication of this new issue on February 1, 2005, I thought it would be timely to tell everyone about this new service provided. It helps you and it helps us by serving you better—faster.

Further, it would be a good idea to update your user name (no change to password though) to an active email if it no longer works. To update, just go to this form which is the same one described in the paragraph above this one:
http://www.antennex.com/lostxpwd.html

The above information has been added in our FAQ to cover many such issues that may arise. Links to the FAQ can be found on the antenneX Front Page and the separate Login Page. The direct link is: http://www.antennex.com/faq/index.htm

AN INVITATION TO CONTRIBUTORS
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antenneX thrives on the contributions of antenna experimenters, ranging from the informal home shop construction project to the theoretical investigation of basic antenna, feedline, and propagation phenomena. Over the years, we have published articles on the use of new or newly adapted materials, known antennas adapted to new circumstances, modifications of antenna structures, basic explorations of both common and unusual antennas, antenna modeling exercises, design improvements, antenna matching techniques from both a physical and mathematical perspective, evaluations of mini-antennas and their underlying theory of operation, new and patentable designs, propagation tutorials, and.... The list goes on, since no antenna-related topic is irrelevant to the readers of antenneX.

At the same time, antenneX has experienced continuous growth in its readership—for which we are appreciative. However, all readers can help us do even better. How? By submitting an article every now and then based on your current antenna work that may be useful at any level to other readers.

Among the engineering and researching readers, there are undoubtedly a number of unclassified and non-proprietary findings that antenneX readers would like to know. Among the practical antenna designers, there are ideas, tests, and numerous other practical findings to benefit our readers. Antenna builders very likely have some techniques to share with other readers. Besides the regular articles, we always have the home work shop column for shorter practical ideas and we always have the invited news and editorial column for information about new technologies, future advances, lost old but good ideas, and personal views on the good to bad things that are happening in the world of antennas and propagation.

If you are uncertain about whether your ideas merit an article, please feel free to send an outline to the general editor/publishers at submissions@antennex.com . Do not feel that you must be ready to be a regular submitter to write for antenneX, because we welcome the individual contribution as much as monthly articles. As well, do not believe that the slots in each issue are already spoken for—we shall always make room for a worthy article.

Planar Reflectors Part 2:
Phased Dipoles and Rectangles
By L.B. Cebik, W4RNL

In part 1 of this exercise, we explored models of a planar reflector using vertical and horizontal dimensions that varied from 1.0 to 2.0 wavelengths per side. The test frequency was 299.7925 MHz so the a wavelength equaled 1 meter. The overall goal of the set of tests was to determine if there is an "ideal" size of planar reflector relative to the particular driver used to complete the simple array. In the initial test set, we used a single dipole as the driver. The data accumulated for the dipole driver left us with a number of questions for which we require further investigation.

Radiation by an AC Voltage Source
By Kirk T. McDonald
Joseph Henry Laboratories, Princeton University

Kirk explains that an AC voltage source is a two-terminal device that supplies the real part of the voltage to a load across its terminals, independent of the details of the load. Then consider an AC voltage source in the absence of any load. The voltage between the terminals is still oscillating, so there are electric fields present, which implies that there must be some charge in motion. In this article, let's examine how that may be.

Dissecting the Pi-network Matching Process
By Fred M. Griffee, N4FG (EE Retired)

This month, Fred states: "In many of my previous articles, I went through the matching network configuration and results, but never analyzed the matching process. In this article, I shall “dissect” the Pi-matching process. The first part of this analysis will show the result of the antenna system drive point impedance in shunt with a variable capacitor and what happens. Many treat a Pi-network as two L-networks back-to-back, which is correct. I shall show that the PI-network can be tuned such that it essentially becomes an L-network for maximum efficiency."

The Neighbor-Friendly Multiband Loop
By Dave Cuthbert, WX7G

This antenna is for those of you who want good DX performance yet have to live with closed community constraints. It covers the 20, 15, and 10-meter bands and is only 6 feet tall, yet has a low angle of radiation. In addition, since it is ground independent and fed with coax, it’s easy to install.

A Homebrew CW Paddle
By Pascal Veeckmans, ON4CFC
Translation by Jef Verborgt

Building and mounting new antennas high up in the air is an activity for the summer months. For the long winter nights Pascal has a fun project that will keep you warm and might motivate you to practice those rusty CW skills.

Portable HF Transmitting Loop Antenna
By David B. Thomas, N5IZU

We have a new contributor this month in an article by David B. Thomas, N5IZU. Operating with a magnetic loop "while on the go." David says while HF antennas are not normally known for their small size, magnetic loops can offer quite respectable performance, at the cost of some efficiency and extremely narrow bandwidth. The tunable magnetic loop antenna described in this article is David's contribution this month to the well-established art of amateur loop making. It is small and light enough to carry while operating; it disassembles into small but rugged pieces that fit easily in a backpack or gym bag and it can be tuned from 14 MHz to 30 MHz.

Well, there you have it, folks—thanks for listening and remember, the reading lamp is always on for you in the reading rooms. If I can be of further help, I'm just a Stone's Throw! away.-30-

Best reGARDS, Jack L. Stone, Publisher
jack@antennex.com
February 2005 antenneX Online Issue #94