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On Sep 6, 1:16*pm, JIMMIE wrote:
On Sep 5, 7:29*pm, Art Unwin wrote: On Sep 5, 6:02*pm, JIMMIE wrote: On Sep 5, 6:37*pm, "christofire" wrote: "Art Unwin" wrote in message ... On Sep 5, 3:17 pm, "christofire" wrote: "Szczepan Białek" wrote in message -- snip -- If you want to discover what radiates I suggest you read one of the normal text books on the subject, like Kraus 'Antennas', and stop making up your own versions! To discower what radiates will be better to do experiments with tipping of monopole antenas. * Where do you get this stuff from? Please visit a library - you could do yourself a lot of good. Chris Chris, what I believe he is referring to is that computer programs support a tipped vertical over one at right angles to earth. Computer programs are supposed to be based on Maxwell's formula. Is this an error and how do we fix it. If it is not an error then it supports the presence of the Coriolis force in collusion with gravity. and not gravity alone. * I don't doubt that it is possible to obtain results from a computer program that appear to contradict conventional theory. *Interpretation of what comes out is always the responsibility of the operator so, whilst anyone can enter parameter values and hit 'go', not everyone will interpret the results correctly. *In this respect it must help greatly to have a clear understanding of the basic principles of how antennas radiate and how the modelling programs operate; in most cases how the moment method works. *My recommendation, as before, is to read an edition of 'Antennas' by Kraus (or an equivalent), cover to cover, before trying to make sense of the output of any antenna modelling program. *Of course, I realise that some who 'publish' here feel this would be beneath them, or too hard ... but, really, it is neither. My own take on the effect of tilting a vertical antenna is that if its length is an appreciable fraction of a wavelength then tilting it will distort its radiation pattern and will upset the uniformity of its polarisation, which will impose a further effective radiation pattern. *If this results in a bit of gain in one particular direction with respect to a particular polarisation then fine, and this may be of some use in amateur radio service although it isn't how vertical monopoles are most often used (i.e. their omni-directional pattern is their strength and there are many other, better ways, to obtain directional patterns). However, the theory on which all the well-known modelling programs is based is the simple stuff described by Kraus, et al, and probably in most cases follows from the original work that led to NEC (http://www.nec2.org/other/nec2prt1.pdf). *It takes _no_ account of the Coriolis force or gravity (outside of its impact on the speed of light). *If such a program produces output that the operator interprets as depending on the Coriolis force then, logically, this must be a mistake on the part of the operator - wouldn't you agree? *However, if you believe the theory on which the program is based is in error then maybe you shouldn't use it. More to the point, it is common knoweledge that there is no full understanding of radiation available anywhere. Thus he is asking probing questions to fill in the gaps. * There is sufficient understanding of radiation and antennas out there, as widely documented, to have enabled practical radio, radar, and suchlike for more than a century. *I understand that part of the point of amateur radio is to encourage experimentation, but I don't understand why experimenters should wish to shun the accepted, conventional theory and try to come up with their own, perhaps paraphysical, versions - especially when those people don't exhibit much understanding of the basics. *Maybe they treat the subject a bit like art (no pun intended) instead of the science that it should be. Personaly I am not willing yet to say antenna programs are at fault until more explanations come about. Can you explain what he is commenting upon.? * It's possible he is being deliberately provocative. Chris It is conceivable that the Coriolis effect may act upon EM radiation. But given the speed of propagation of the radiowaves the effect would truly be miniscule. I Art thinks the rotation of the earth has any significant effect on EM propagation he should show some reference. Im not going to hold my breath until that happens. Jimmie I have always followed the particle approach over the EM route. *The reason I have followed this path is that Gauss's law dictates it and computer programs support it. There has been no move to doubt programs so I assume they are according to Maxwell and the errors are else where. So let's go back and leave these assertions that have been erroniously pointed at me and look at the Gaussian/ Maxwell observation which I have pursued. I have posted the original statement and look for those who have expertise in the area to post their views and why. So Jimmie you have been prolific with your thoughts and insults, allow us to view the mechanics of what ever decision you make whether it is a repeat of David or one that shows your own method of thinking. Thanks in advance Art Dave has posted his reasons why he feels my assertion is false- Hide quoted text - - Show quoted text - Art, it would be nice if you posted reason to why you think your assertions are true instead of just posting random assertions. Why should I waste my effort trying to explain why you are wrong when you refuse to make any effort to show why you are right. Jimmie Jimmie the answer resides in the question posed. If you have a track record such as a degree where you can explain academically, place your input or be declared a follower. 2;1 against me so far but I need a couple more. So far there has been much more that have commented but I have to sort intuition from academics to decide on the playing field |
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