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Cecil:
Maybe I sent you the wrong .EZ file. Anyway, I went back and pondered over your example, DUH!, it was obivious, I simply had to splilt the driven element into two sections where the gamma joined it! Oh well, I might have made myself look stupid today, but not to such a great extent that I won't be able to top that tomorrow!!! Regards, John -- I would like to point out, I do appreciate the "Been there--done that!" posts. Indeed, now your observations, comments and discourse should be filled with wisdom--I am listening!!! "John Smith" wrote in message ... Cecil: Here is an EZNEC file I am having a problem with, it is complaining about wires 5 and 2 NOT meeting at an end or segment? What corrects this? Thanks in advance, warmest regards, John -- I would like to point out, I do appreciate the "Been there--done that!" posts. Indeed, now your observations, comments and discourse should be filled with wisdom--I am listening!!! "Cecil Moore" wrote in message ... Cecil Moore wrote: I knew I was confused about what you were trying to do. John, I just realized what is wrong with gamma feeding a 1/2WL vertical at the base. The currents in each side of the gamma feed section are pretty much out-of-phase so they don't radiate (much). Conclusion: Gamma feeding a 1/2WL antenna at the base results in a field strength comparable to a 1/4WL vertical and the minuscule amount of gain is not worth the effort. Antenna gurus probably already knew that but it just dawned on my concrete brain. In much the same way a Zepp or a J-Pole is not a 3/4WL radiator even though they are 3/4WL long, a gamma match on a base-fed 1/2WL vertical doesn't yield a 1/2WL electrical radiator. For this reason, the length of a gamma match should be considerably less than a wavelength. A good rule of thumb is probably in the ballpark of less than ~6% of a wavelength. Your idea seems to require about 16% of a wavelength. Moral: Physical length and RF electrical length are not always the same. What you are trying to do apparently requires a J-Pole or Zepp approach, i.e. a physical 3/4WL antenna. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
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