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I hope you were reading my recent correspondence about digital RF sources (seems like it would be a natural for your own digital project). Well, as for fooling around, I'm off to the campus for more Nanotech. 73's Richard Clark, KB7QHC Thanks! Yes, I am trying to keep up with all the new stuff, plus some older, I have been out of main stream circuit design for a while, but looks like the timing is just like back then on the trehshold between sparks and tubes. One think that our dual channel DSPed RX will allow is to stear the antenna patterns and some far out noise elimination and processing. We have standing invitation to the brightest minds among hams to contribute or participate in the Dream Radio One project. www.computeradio.us Yuri, K3BU |
Richard Clark wrote in message ... On Tue, 19 Oct 2004 10:03:10 -0700, "Chuck" wrote: I have for a long time, suspected there was a tx line modeling problem in NEC. Now, it is apparent this problem exists only in your EZNEC. Hi Chuck, You asked how to avoid this (if indeed it exists), and I offered a very simple response to which you have had no comment. Hi Richard, To be blunt, I didn't see any merit in your suggestion. (1) there are no modeling alternatives for this problem, and (2) it failed to address the issue: Roy's apparent omission of the thin-wire model in his EZNEC, which he touts as a complete NEC application. I suggest you re-read the posts if you truly are interested, then read the NEC2d documentation to confirm. As far as independent empirical testing is concerned, there is nothing new to be learned other than revealing EZNEC's shortcomings in this regard. Roy has offered a means to have a third party verify your claims, independent of his software such that it comes down to you are right, or he is right. You have not taken this offer I accepted Roy's offer, but with conditions. So far, he has declined to accept those conditions. I did accept Chip's offer, though. IRT your other oratory ramblings: Incoherent nonsense... 73 de Chuck, WA7RAI |
I accepted Roy's offer, but with conditions. So
far, he has declined to accept those conditions. I did accept Chip's offer, though. IRT your other oratory ramblings: Incoherent nonsense... 73 de Chuck, WA7RAI Yep:-) Sure did. I posed no conditions nor restrictions for Chuck. It's his antenna and his technology. I don't have any bias on how or why it works; I'll just measure it. Period. I will have no problems testing it with a professional outdoor range setup. No 's' meters here, friends. If a third party has offered to pay for the tests if they meet Chuck's extant specs, that's fine with me. In fact, my inclination at this point is to have that third party pay up directly to Chuck. I'm happy to do this for Chuck, gratis. Chuck can do what he wants with the data. Always happy to help a colleague. 73, Chip N1IR |
IRT your other oratory ramblings: Incoherent
nonsense... 73 de Chuck, WA7RAI It READS like language, but I don't know what to make of it.... 73, Chip N1IR |
Sigh.
It's really a shame that I have to keep returning to this bashing session just to correct the false statements about EZNEC that Chuck keeps inventing. He did, at least, give the thread an honest and appropriate name. Responding only to his mistruths: Chuck wrote: To be blunt, I didn't see any merit in your suggestion. (1) there are no modeling alternatives for this problem, and (2) it failed to address the issue: Roy's apparent omission of the thin-wire model in his EZNEC, I clearly stated in an earlier posting that EZNEC implements the extended thick-wire kernel as required by the model. (The thin-wire kernel is the default.) Chuck has chosen to either disbelieve or ignore this, although I have no idea why he even cares about EZNEC's inner workings. Once again, I welcome any example of disagreement between EZNEC and NEC-2 modeling results. (Those which have been submitted in the past have nearly always been the result of the models indavertently being different, the most common error being due to the use of wire radius in NEC-2 and diameter in EZNEC.) which he touts as a complete NEC application. I have never, at any time, claimed that EZNEC does or would implement all the features of NEC-2, so Chuck will never be able to support his fabrication. The lack of "patches" in EZNEC is in itself a difference that's obvious to anyone with even a superficial acquaintance with NEC-2. What I do claim is that EZNEC uses NEC-2 for the calculations it performs, and that the results one gets from EZNEC will be essentially identical to NEC-2 results. EZNEC does have many features not present in NEC-2. I don't know what's motivating Chuck to continue making false statements about EZNEC, but I caution readers to look at the record, archives, or other sources of information before believing what he says. You can't say you weren't warned -- just look at the thread subject. Roy Lewallen, W7EL |
Someone going by 'Bob':
Someone has to produce an example. "Richard Clark" ...I've done that here through modeling too using exactly your point. The results were trivial, but for some, extremely hard to swallow. [**] ;-) Can you clarify your findings (please and thank you)? Were you able to find an antenna system (pair) that displayed direction-dependant pathloss? Since you can't prove a negative and I know that you know it, I assume that you did. If so, perhaps you could post the example on your website. **joke**: Monica Lewinsky is voting Republican this year; the Democrats have left a bad taste in her mouth. |
On Tue, 19 Oct 2004 13:29:39 -0700, "Chuck"
wrote: To be blunt, I didn't see any merit in your suggestion. (1) there are no modeling alternatives for this problem, Can't construct a coaxial line from wire elements? Tedious perhaps but not impossible as you would suggest. and (2) it failed to address the issue Then perhaps this is a moving target. Hi Chuck, Well, now that is quite odd in that when I posed this solution earlier you agreed is was in fact achievable. Now that you deny it as a solution I can only interpret that you do not see it concludes your speculation to your advantage. IRT your other oratory ramblings: Incoherent nonsense... You mean you couldn't understand my anticipation of your proceeding to no particular resolution and the continuation of repetition and denial? :-) Difficult concepts, but obviously demonstrated. 73's Richard Clark, KB7QHC |
On Tue, 19 Oct 2004 19:10:01 -0300, "Bob MacBeth"
wrote: Someone going by 'Bob': Someone has to produce an example. "Richard Clark" ...I've done that here through modeling too using exactly your point. The results were trivial, but for some, extremely hard to swallow. [**] ;-) Can you clarify your findings (please and thank you)? Were you able to find an antenna system (pair) that displayed direction-dependant pathloss? I've use EZNEC to demonstrate any number of "impossibilities" all without violating or compromising the modeler's constraints. The effects were trivial to say the least, but demonstrated that Axioms of antenna theory had limitations that were unexpressed (until you got to the graduate level of the same sophomore course work). Since you can't prove a negative and I know that you know it, I assume that you did. If so, perhaps you could post the example on your website. Well, it has been a great while in this particular instance of path reciprocity. I did use the scale of range you suggested (and perhaps further). It was not so much about loss however, but the failure of reciprocity (a common topic in photography - which, here, is an aside). I frequently use two or three antennas in one model, with the second/third being receive models with termination resistors. They would be called sniffers in field work or bench work. This work that I engaged in had no particular demonstration of your curved field issue (which, through simple abstraction suggests any differences you would observe would be out several decimal places and beyond the ability of any instrumentation to resolve with accuracy). Then again, maybe it did (it may have involved an inclined sniffer which demonstrated the curvature in one direction, with a corresponding difference in the other). I would suggest you simply follow this last speculation and see where it takes you. I suppose you could search the archives for my name and the key words of "reciprocity failure" and confine the search to the mid to late 90s. 73's Richard Clark, KB7QHC |
"Richard Clark"
I've use EZNEC to demonstrate any number of "impossibilities" all without violating or compromising the modeler's constraints. ... Merci. |
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