The EH - ITSA HERTZ?

lease bear with me about the play on words, but I just couldn't resist. Not since the CFA has there been such a heated debate as there is now about another device called the "EH", one of the latest attempts to fill the void and serve as the ultimate answer for an efficient compact antenna. The "play" on words is a result of the promoters' claim that this device makes the conventional "Hertz" antenna obsolete. Later, the reason for the title will become more evident and appear appropriate.

OVER & OUT HERTZ?
A few months ago, one of the promoters from Italy paid a visit to just about every amateur radio reflector with a similar announcement about the launch of the EH. In the interest of accuracy, here is the pertinent part of one of those announcements (with minor edits for clarity):

Well, that last statement about replacing Hertz lit a fire under the other members of the various lists, and the heated debates commenced, although some genuinely expressed hopes that the mighty claims were at least somewhat true and asked some very reasonable questions about the technical aspects of the device. Additionally, more questions were posed about the extent of tests conducted. While the promoter was being pelted with questions and criticism by the skeptics, the biggest complaint was that the answers were evasive and without any kind of substance that was convincing. One such response triggered frustration that summed up the feelings this way:

Apparently, some willing and open-minded participants conducted a number of experiments but with mixed results, while none reported results that measured up to the claims of the promoters. There were and are the usual concerns and debates about radiating feedline and coupling with other antennas or surrounding objects. Explanations about this have been filled with contradictions.

As indicated above, there are truly some folks who would like to give the EH a chance, but even though the recipes given out have been diligently followed according to the experimenters, the results have not been very good and the usual response from the Italian promoter is that it was built wrong. Another ham in Italy located some 150 miles away from the promoter offered to participate in an exchange of signals with his conventional dipole used to receive from a "factory-built" EH. The feeling was that if one could be built properly, it should be the promoter. That offer was made more than a month ago and still silence has persisted at last report. Seems like a reasonable test to perform without much effort even though it would not be entirely conclusive without sufficient answers about the manner of hookup, etc. Needless to say, this has not inspired others to do more experiments as it is reminiscent of the discouraging experience with the CFA, from which the EH is supposed to have been derived.

BUT EH FAILS AM TESTS
Moreover, for a protracted period of time, the promoter of the EH has been trying to obtain a license to conduct an AM test under the FCC guidelines using the facilities of a broadcast station in Georgia, USA. That license was granted, tests were conducted but the EH failed the tests, all according to the promoter. The reason given was that the matching network used was more appropriate for the HF version of the EH than the broadcast version. Plus, it was decided that the original design phase shift assumptions were wrong. Back to the drawing board!

Does the above sound familiar? It should, as the pattern of evasiveness is taking a path similar to the CFA that we have watched over the past several years. Getting solid facts and figures were almost impossible and if any experiments failed, it was usually attributed by the promoters to have been built or tested wrong by the experimenter. This experience with the CFA has only added to the skepticism toward any new device that makes great promises. At least the CFA showed some visible physical promise in that many broadcast sites were springing up in various parts of the world. The EH remains pretty much in the "prototype" stage.

EH ALREADY PATENTED?
Moreover, another factor loomed in the background. As reported more than a year ago, the CFA co-inventors claimed that an EH was an earlier invention of theirs while in the process of developing the CFA, some 10 years ago. This version without a cylinder was not found to perform very well and they remained focused on the cylinder and plate version of the CFA. Dr. Kabbary has stated that one of the EH versions was still operating on an old steamship (apparently making use of the steel hull as part of the radiator?).

Thus, the co-inventors believed the EH probably infringed upon their earlier invention that had been filed of record. It was believed that the CFA inventors were waiting to see if and when the EH showed any commercial value before challenging the question of infringement on the presumption of "why waste money on attorneys if there is nothing of value to fight over?"

During the past month, the EH attracted closer scrutiny from Dr. Kabbary and after giving it more thought, he reasoned that the EH was NOT an EH after all, but was only an E antenna, and to quote Dr. Kabbary more closely (minor edits only):

Thus, does Dr. Kabbary's observations above now consider the EH to be just another conventional antenna—if so then.... ITSA HERTZ after all! Once again, only the "test of time" will tell the full story!

THE EH ANALYZED
As with other new concepts, several of the members of the GARDS have experimented with the EH. So far, none of the results show any better performance than the other capacitor-type compacts. Actually, there is a great deal of discussion about exactly how to classify the EH device, which is not yet firmly classified by observers as an antenna per se—so. we'll refer to it as a device with more certainty for now. In this month's issue, our science writer and GARDS' member Joel Hungerford presents an excellent article which describes the results of his own investigation into the EH during the past month. He has employed the use of the computer software Pspice which seemed appropriate to this type of design with its various circuits. We've placed a copy of the article about that investigation in the Ham WorkShop at this URL: "The EH Analyzed" Meanwhile, we continue to look for the ideal compact antenna.

MAGNETIC LOOP CAPACITOR WORK IN PROGRESS
Once again the ingenuity of our GARDS' member Pascal Veeckmans, ON4CFC continues to amaze us. Pascal sent me a pile of fresh pictures of a new motorized 8pF...44pF capacitor concept he is working on. With this being one of the most difficult components in the configuration of a magnetic loop, I thought the reader would enjoy taking an early look at what Pascal has dreamed up as another solution for this device. Below is a tour of the illustrations just received, starting with his drawings and then moving over to some real construction. These early illustrations may not only be of help to you on a similar project, but generate other ideas to build from:

Sorry I don't have a narrative for you, but Pascal has promised to write this up and present to us the finished version with all of the details perhaps in the next issue of antenneX.

XMAS SPECIAL
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Pursuing the (Nearly) Perfect Parasitic Vertical Array for 160 Meters
Part 1: A Review of Design and Modeling Techniques
By: L.B. Cebik, W4RNL

Suppose that you had a vertical array for 160 meters that produced an azimuth pattern and that the elevation angle is 15 degrees, and that the peak front-to-back ratio is nearly 40 dB. What might it take to achieve such a pattern? In most instances, folks would speculate on phased monopoles. Now let's add the ability to remotely switch the direction of the array in 60 degree intervals throughout the entire circle. What might that ability require? Find out in this feature by LB.

LAB NOTES: Top-Loaded MagneTITE Antenna
By Joel C. Hungerford, KB1EGI

In the November 2001 issue of antenneX, Joel described a vertical monopole antenna that tuned in the 15-meter band and what affect the use of magnetite had in making this antenna tune down to the 20-meter band. As the next step, this month he investigates and describes the affect of the method of lowering the tuning frequency, adding a capacity hat to the top of the antenna, both with and without magnetite.

The Broadband Vertical Asymmetrical Antenna
Part 2: Exponential Antennas
By Igor Grigorov, RK3ZK

Igor has another unique article for us this month and, as usual, makes a very thorough presentation, fully illustrated. The antennas described in this article are among the oldest form of vertical asymmetrical antennas. All of these antennas were developed prior to and up to W.W.II. During that war, these antennas were installed on ships, military communication centers and other important communications sites. One type of planar asymmetrical antennas, which is described in this series of articles, was even installed on airplanes. Subsequently with increased advancement in this type of antenna, they were designed and built for use in the VHF ranges. These VHF antennas were extremely broadband. Don't miss this very interesting Part 1 on this particular subject of a special but very conventional type of broadband antennas.

THE RING ANTENNA - Going Mobile On 2 Meters
By Pascal Veeckmans, ON4CFC
Translation by Jef Verborgt

J.M. Boyer is known for inventing the DDRR. He also invented another device called the Ring Antenna in 1963 under US Patent No. 3247515. This time it was a lambda/2 Ring Antenna that is more forgiving and this lambda/2 Ring Antenna has a much wider bandwidth. In its original form it also makes use of a small trimming capacitor. In this article Pascal shows us that a lambda/2 Ring Antenna can be built on the roof of a car without a trimming capacitor and all this with a decent performance and a low profile to boot for parking in your garage!

The 40-Meter Stealth Vertical
By Robert E. Houf, K7ZB

The need for a 40-meter antenna that would perform well and not violate the spirit of the Home Owner's Covenants protecting the aesthetics of the neighborhood was the driving force behind the design of this vertical. This antenna was designed to provide low angle radiation for good DX performance during the nighttime hours. DX on 40 meters is best when the local sun is down and this makes it convenient to use the cover of darkness to hide the size of a quarter-wave antenna. Especially one mounted 12 feet above ground that puts the top of the vertical at nearly 50 feet!

Modeling the Double-Diamond for UHF
By L.B Cebik, W4RNL

The double-diamond quad has become a "hot" antenna in Europe. Introduced in Germany some years ago, the antenna has "taken off" and become somewhat a darling among home-brew antenna fans, especially on 432 MHz, where the usual double- diamond array can cover all of the band. Two recent articles in antenneX have featured the double twin quad in various arrays, along with certain circumspectly veiled claims for its gain. As well one of the articles noted that LB would try to model the antenna, so LB accepted the challenge and this article presents his modeling results.

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. December 2001 antenneX Online Issue #56
reGARDS, Jack L. Stone, Publisher jack@antennex.com