From this comes antennas!

INTRODUCTION
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nd from this comes antennas! This is a "catch phrase" from one of the most spirited threads in the June 2004 antenna-discussion list. In fact, it is one of the most discussed subjects since an earlier month's thread about how photons manage to escape the antenna.

The phrase is borrowed from a wonderful essay authored by Kirk T. McDonald. Many agree it is a most comprehensive, clear and well-written "paper" about the subject of how things work within an antenna's properties, specifically dealing with the issue of displacement current.

Kirk's own well-developed theories about this subject of displacement current also deals with the proper interpretations of terminology used within the theories from some of the masters, Maxwell, Newton, Oersted, Faraday and Ampere whose "laws" have been challenged time after time for more than 100 years. Much of one's ability to understand the masters is to try and get into their minds in a time period of 150 years ago when so many things were only known in theory. Kirk has shown himself to be most skillful at doing this and truly is a very talented educator!

I liked this dissertation well enough to turn it into an article with permission and final edits from Kirk, a regular contributor/educator within the antenna-discussion list. I thought we should share this dissertation with our readers. Anyone who misses out on this presentation misses a real jewel of a document. So, don't miss the article if you are interested in learning more about how antennas work. It might also be considered as a point or counterpoint to Bill Miller's third article on displacement current mentioned below.

Kirk McDonald is a professor of physics at Princeton University, where his research centers on experimental elementary particle physics. Since particle accelerators are essentially boxes with antennas on their walls that radiate inwards, McDonald has long been fascinated with unusual aspects of electromagnetic waves.

As an exotic example, he was the leader of a project that demonstrated how gamma rays could interact with a laser beam to produce antimatter. Many of his other articles on electromagnetism can be viewed at his website:
http://puhep1.princeton.edu/~mcdonald/examples/

AN INTRIGUING NEW DISCOVERY?
About a year ago, antenneX published the William C. (Bill) Miller's 2-part article called, "Displacement Current Does Not Exist." Bill said the article series was prompted by the performance failures found in two classes of antennas - the CFA (Cross Field Antenna) and the EH. The inventors of both antenna types claim that they "use" displacement current as an integral part of the radiation process.

Bill's previous articles argue that the derivation of the concept was flawed, and that Displacement Current did not exist. Despite substantial criticism from classically trained engineers and physicists, the author stands by the contents and premise. Nevertheless, the author was unable to answer the one question that appeared again and again: "If Maxwell's Equations are wrong, what does he propose as an alternative?"

Using information not available to Maxwell in the 1800's, Bill's new article this month, How a Capacitor Really Works, re-examines how current flows in a wire and, subsequently, through a capacitor.

Bill takes the information gained from his research to derive a new set of Maxwell's Equations. He claims the new equations are consistent with current theory and practice, consistent with current knowledge of how electrons and fields interact. Bill says it explains why the CFA and EH do not work as claimed and perhaps solves at least one discrepancy between antenna modeling and actual performance.

Bill is to be admired for his courage to challenge the "Masters" and make his own tracks in the sand. He is also a very skilled writer so as to convey his ideas with clarity to the rest of us. Moreover, Bill is without arrogance in his concepts that may (or may not) depart from those established long ago. He did not set out with the goal of challenging the masters, but only to present his ideas for consideration, realizing he may have to absorb some lumps along the way. The "path of knowledge" is not a dead-end and I suspect we'll be reading more about Bill's ideas presented this month.

William C. (Bill) Miller holds a BSEE from the University of California, Berkeley. He has held Engineering, Product Management and Marketing positions with a variety of well-known companies, including Eitel-McCullough, Ampex, Schlage and Yale.

In the late 1980's he tired of corporate life. Bill and his Fijian-born wife, Sardha, now own a chain of floral shops in Charlotte, NC. In his worldwide travels, he became familiar with a wide variety of cultures. He speaks Spanish, French and Portuguese as well as having a working knowledge of German, Italian, Japanese and Hindi.

Bill has been a licensed radio amateur since 1957 and holds an Advanced Class license with the call sign KT4YE. He is an active member of the GARDS, an International Group of compact antenna researchers.

Indeed, Bill is very bright and courageous in this technical field almost without boundaries for new concepts and experiments.

A warm welcome to Fernando J. Muguerza, XE2FL of Mexico
Fernando writes a Bulletin called Radio Sucesos that is an official publication for ARARM, the largest radioamateur association in Mexico. Fernando is also the ARARM National Secretary.

Fernando's brief radio BIO and operating station:

I passed my Mexican License test in 1955 and obtained my XE2FL call (First Class). I hold DXCC (First XE Mixed DXCC), now with 320 countries confirmed on Phone and 321 mixed and 2 WAY SSB WAZ on 20 Meters.

Also hold A USA Call Extra Class, which is KF5MN.

My Antennas are:
20 Meters: 5-element wide-spaced Yagi with 14-meter Long Boom at 17 meters high
15 Meters: 4-element Yagi at 12 meters high
40 Meters: Folded Dipole at 20 meters high
Transceiver: YAESU FT990DC, 100 WATTS

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Fernando's Station at 756 meters above sea level
and 222 meters above overlooking the city of Monterrey, Mexico.

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.

Extending the 2-Meter OWA Family
Part 1: 13 to 20 Elements and a Self-Limiting Design
By L.B. Cebik, W4RNL

In a past 2-part series devoted to developing the optimized wide-band antenna (OWA) concept to full-band Yagi antennas for 2 meters, we examined a connected series of antennas ranging from 7 to 12 elements. That series elicited a number of requests for longer versions of the antenna, given its adequate but stable gain, very good front-to-back ratio, exceptional SWR curve across the band, and general attenuation of sidelobes to more than 20 dB down from the main forward lobe. The results have yielded more surprises.

Hardening the 20-Meter Loop
By Joel C. Hungerford, KB1EGI

Last month Joel described a loop antenna designed for 20 meters that he intended to use for the next local ham radio “field day”. This month was spent “hardening” the antenna to withstand the rigors of moving it to a simulated “emergency” site. The method of feeding the loop was improved to eliminate tuning and the interlaced-wire capacitor was mounted onto the loop. The loop was then operated in various spaces ranging from among the tools and tables in the shop to sitting on the edge of the roof. The loop Q was measured in seven combinations of site and cable length to the transmitter; the efficiency as indicated by Q was computed using the formulas in the excellent article by Claudio Re last month. Joel was surprised how rapidly the cable length degraded the efficiency of the loop.

Yagi-Uda Antenna Design and Optimization: Part II
By Fred M. Griffee, N4FG (EE Retired)

After Yagi and Uda developed the new antenna array design concept, others studied and contributed to the approach. There has been extensive analysis, design, and contribution to the original Yagi-Uda antenna approach since 1926. Fred models the seven-element Yagi-Uda Design using YO7.6 and NEC-Win Plus software. This article is an example of the beginning process of combining YO7.2 and NEC-Win Plus. The Part II examples become more advanced.

… and, from this comes antennas!
By Kirk T. McDonald
Joseph Henry Laboratories, Princeton University

Kirk is fascinated by the continued confusions over the concept/meaning of "displacement current" by some members of the antenna discussion list. Of all groups within society, antenna builders/users are the most affected by the abstraction that has come to be known as displacement current, and hence should have the greatest appreciation of its significance. Yet, the opposite seems to be true as observed by Kirk.

Only after Maxwell developed this concept were people's minds freed enough from past prejudices about electricity and magnetism to be able to conceive of the experiments that resulted in broadcasting and receiving electromagnetic waves via antennas. But the ongoing discussions emphasize that electromagnetism is much more abstract than, say, mechanics.

Some Methods To Improve Compact Loop Performance: Part III
By Claudio Re, I1RFQ

Recently, on the antenneX antenna discussion list, several contributors expressed interest in learning more about improving the performance of compact loops. This was prompted, in part, by the introduction of some new antenna concepts based on recent articles on the “Cubes Family.”

The most common question seemed to be “What techniques are available to significantly improve the performance of compact loops?” Over the last few years, the author has spent quite a lot of time reviewing this subject from the point of view of the ham radio operator. This article series contains some of the results of these studies.

HOW A CAPACITOR REALLY WORKS
By William C. Miller, KT4YE

In the 1860’s, James Clark Maxwell postulated the existence of Displacement Current as the mechanism whereby Alternating Current (AC) flows through a capacitor. It forms the keystone in a series of equations — often called Maxwell’s Equations — that are the basis of all Electromagnetic theory.

About a year ago, antenneX published the author’s 2-part article called, “Displacement Current Does Not Exist.” The article was prompted by the apparent failures to perform as claimed found in two classes of antennas — the CFA (Cross Field Antenna) and the EH. The inventors of both antenna types claim that they “use” displacement current as an integral part of the radiation process.

Bill's earlier articles argued that the derivation of the concept was flawed, and that Displacement Current did not exist. Despite substantial criticism from classically trained engineers and physicists, the author stands by the contents and premise. Nevertheless, the author was unable to answer the one question that appeared again and again: “If Maxwell’s Equations are wrong, what do you propose as an alternative?” Bill believes he now has found that alternative set of equations and once again, Maxwell has been challenged!

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. July 2004 antenneX Online Issue #87
reGARDS, Jack L. Stone, Publisher jack@antennex.com