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![]() ----- Original Message ----- From: Walter Maxwell To: Ted Sent: Tuesday, January 13, 2004 3:20 PM Subject: EH Antenna Hello Ted, Thank you for your response to my note to Bill. Ted, I'm sorry to have rained on your parade, but I have not seen any proof that your antenna outperforms any Hertzian antenna as you claim. As I read in the 'Article' appearing on your web site, you are claiming that when your 'EH' is at 1/4 wl above ground it has a 2.25 dB gain over a standard 1/4 wl vertical. I have reviewed very carefully the engineering document prepared by the broadcast consulting firm of Graham Brock, Inc., who performed extensive field strength measurements on your EH antenna at experimental WK4XVQ in Eatonton, GA, operating on 1520 KHz. To summarize very briefly, their report first shows an average of approximately 1.1 dB less power radiated than the reference standard antenna. Second, it is noted that the test antenna atop a 90-foot tower was coupled to the standard WKVQ tower during the measurements, which is very likely the reason the azimuthal plot of your EH antenna is scalloped rather than circular. I'm sure you're aware that nearby objects that are resonant at the measurement frequency will distort the readings and thus distort the resulting data. What was done at the feedpoint of the WKVQ antenna to eliminate the possibility of its becoming a part of the antenna system? Were the input terminals shorted? Left open? Were any measurements made under both of these conditions to determine whether the the WKVQ antenna was performing as a parasitic radiator? From the measurements performed by the Graham Brock engineers the resulting data shows evidence that that rather than achieving gain over a standard antenna, the EH antenna performs less well than the standard antenna. At this point I'd like to repeat what I stated earlier concerning the concept of your EH antenna's performance resulting from changing the time relationship between the E and H fields to increase the radiation. What I stated earlier is that the development of the continuous alternating E and H fields cannot be changed in any way--not by changing the phase of the source current, or by any other means. The laws set forth by electromagnetic theory are immutable. And I also repeat--the antenna you believe to be performing in a new manner is simply a shortened, inductively-loaded Hertzian antenna performing in its conventional manner. I believe you should consider the following academic treatment that should help convince you that you cannot get additional power for nothing. Assume a 1/4 wl vertical antenna with zero ohmic resistance working over perfect ground. In this condition the only resistance in the system is radiation resistance, and ALL power delivered to the antenna is radiated. Consider now an imaginary hemisphere surrounding the antenna. When power P is delivered to the antenna and all of the power radiated is then integrated over the entire hemisphere, the integrated power will equal power P exactly. Now, because all of the power delivered to the antenna is radiated, any increase in radiated power due to some change in the configuration of the antenna is impossible. Therefore, this constitutes proof that your claim of gain with the EH configuration is invalid. You say you have three patents on the EH. In so doing you have accomplished what many before you have accomplished--outwitting the patent examiner who lacked sufficient knowledge of the subject to recognize an invalid concept in the patent application, and granted the patent. You may not have been aware that hundreds of patents have been declared invalid for this specific reason. Ted, I have no doubt that you honestly believe that your EH concept is correct and valid, and that your antenna is performing within that concept. However, now that you are made aware of the invalidity of the concept, and if you continue to manufacture and sell your antenna as advertised to perform as you say it does, then you must also come to believe you would be misleading the public. In this litigious society don't be surprised if someday an attorney hands you a paper claiming fraud. I would not like to see that happen. Finally, if you still choose to believe my comments are incorrect, then I would suggest you consult with other RF engineers to obtain their expert opinion, many of whom have far greater intellect on this subject than I. You can find some eminently qualified engineers in the news group rraa (rec.radio.amateur.antenna) by simply going to 'find' and inserting 'EH'. Cordially, Walt, W2DU |
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