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#41
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The inefficiency of short antennae compared to long antennae,as previously discussed.
On 10/22/2014 2:13 PM, gareth wrote:
"No A1A required" wrote in message ... On 22/10/2014 19:05, gareth wrote: "Mike Tomlinson" wrote in message ... Attention. He's a very sad, demented attention-seeking troll, as evidenced by the Google archive of his posts dating back to 1997. What's striking about them is that they haven't changed much in that time. Yet again, the abuse that you seek to lay at my door originates with you. How can the truth be 'abuse'? Grow up, Not-Ham Hull, G7KUJ Do you guys not get that this is the sort of conversation he actually seeks? When you continue to respond to him, you give him what he seeks and so he continues to post. -- Rick |
#42
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The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/2014 20:54, rickman wrote:
On 10/22/2014 2:13 PM, gareth wrote: "No A1A required" wrote in message ... On 22/10/2014 19:05, gareth wrote: "Mike Tomlinson" wrote in message ... Attention. He's a very sad, demented attention-seeking troll, as evidenced by the Google archive of his posts dating back to 1997. What's striking about them is that they haven't changed much in that time. Yet again, the abuse that you seek to lay at my door originates with you. How can the truth be 'abuse'? Grow up, Not-Ham Hull, G7KUJ Do you guys not get that this is the sort of conversation he actually seeks? When you continue to respond to him, you give him what he seeks and so he continues to post. Yes, we are fully aware of his mental situation. Sometimes, to speed up the legal side to a custodial sentence, it is necessary to engage with him. Worth it in the long term. -- Collecting Bitcoins for my Pension Please send BTC to 1kZKQMvVPce11u7xG1KbArtrAenuxdZue I thank you! |
#43
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The inefficiency of short antennae compared to long antennae, as previously discussed.
"No A1A required" wrote in message
... On 22/10/2014 20:54, rickman wrote: Do you guys not get that this is the sort of conversation he actually seeks? When you continue to respond to him, you give him what he seeks and so he continues to post. Yes, we are fully aware of his mental situation. Sometimes, to speed up the legal side to a custodial sentence, it is necessary to engage with him. Worth it in the long term. A couple of childish individuals who seek to justify their bad behaviour by claiming that I seek it? Far from it, I seek only technical excellence as I had done for many years. |
#44
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The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wayne" wrote:
"Steve" wrote in message ... On Wed, 22 Oct 2014 17:36:31 +0100, FranK Turner-Smith G3VKI wrote: "Wayne" wrote in message ... "gareth" wrote in message ... Try this ... http://farside.ph.utexas.edu/teachin...es/node94.html This is one of a series of lectures by a prof at Texas Uni. In fact, if you go right back to the home page of http://farside.ph.utexas.edu/teaching, this leads to a most excellent revision of the necessary EM theories, and, briefly glancing thereto, the post grad stuff even exceeds my current interest and knowledge. I'm fairly sure now that this area is where I came across the governing formula that I alluded to recently in this NG when doing my own revision previously in 2005, although the URLs and lecture node numbers have changed since then. When I get time, I'll browse through the links. However, back to your original assertion that your theory has short antennas as being inefficient compared with longer antennas (I'm assuming you are talking half wave dipoles and such). If 10 watts is delivered to a short antenna, where does it go if it is not radiated just as well as 10 watts delivered to a long antenna? Dissipated as heat? # Probably proportionately more will be lost as heat as a very short # antenna will be a low impedance, therefore current, driven job and I sq*R # losses within the antenna will play their part. Apart from those # additional losses, it should radiate all that is left, ... I think. Actually no. The loss resistance tends to be dwarfed by the radiation resistance, so losses in the antenna are not the problem. The problem is matching. A small antenna has a narrow BW so you tend to need a matching system. That is where the losses will be, plus in any feeder. Of course, if you only need a narrow BW and can arrange a low loss feeder plus load the pa correctly, then pa is happy, low feeder loss, the RF gets to the antenna. The antenna RrRL so antenna loss is low. RF has only one place left to go, to be radiated. But I^2 R losses are not part of the theory Gareth presented |
#45
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The inefficiency of short antennae compared to long antennae, as previously discussed.
Brian Morrison wrote:
On Wed, 22 Oct 2014 17:29:29 -0000 wrote: Just where has Fitzpatrick revised anything in EM theories? I think the OP meant 'revision' as in material used to revise for an exam or test. He didn't mean that the theory was changed. It is a UK vs US English thing I find with a little research. No one this side of the pond uses the third definition. It would also help if the original OP didn't write like he was being payed by the word. revise 1. to amend or alter 2. to alter something already written or printed, in order to make corrections, improve, or update 3. British. to review (previously studied materials) in preparation for an examination. -- Jim Pennino |
#46
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The inefficiency of short antennae compared to long antennae, as previously discussed.
"Brian Morrison" wrote in message
k... On Wed, 22 Oct 2014 17:29:29 -0000 wrote: Just where has Fitzpatrick revised anything in EM theories? I think the OP meant 'revision' as in material used to revise for an exam or test. He didn't mean that the theory was changed. Yes, the URL was different from my 2005 printout |
#47
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The inefficiency of short antennae compared to long antennae, as previously discussed.
"Brian Morrison" wrote in message
k... On Wed, 22 Oct 2014 17:29:29 -0000 wrote: Just where has Fitzpatrick revised anything in EM theories? I think the OP meant 'revision' as in material used to revise for an exam or test. He didn't mean that the theory was changed. Oops, yes. 33 years after studying to that level and not using that theory in theinterim. |
#49
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The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/2014 17:42, John S wrote:
On 10/22/2014 11:10 AM, gareth wrote: "Ian Jackson" wrote in message ... In message , rickman writes On 10/22/2014 11:15 AM, John S wrote: What the hell are you seeking? Drama And, of course, confrontation. Untrue. The confrontation is sought only by those who seek to respond in a tendentious and abusive manner, such as John S and rickman above. In what way have I been abusive, Gareth? As for tendentious, it you who have done so with most all of your original posts. It seems to me that you are a lost and lonely soul and are seeking some attention. If you wish to discuss technicalities of ham radio, I'm all for it. Can we please be gentlemen about it? If not, I will never respond to you again. Welcome to the club. I disagreed with him and so have been labelled as abusive. Each time he comments that I have been abusive I request that he posts a link to the post where I abused him. Oddly he has never managed to do so on any single occasion. In reality he has hurled abuse at me for being a warmongering baby killer after spuriously deciding that I was in the army (I posted that I had used military comms, I had when liaising between RAF and mountain rescue I am a qualified mountain leader and ex-rescue). Funnily enough he could come up with no evidence that I was ever in the army either. (I wasn't by the way but I was in uniform in the cubs in the 70s - we never actually went to war in the cubs but I did make a pointy stick once). You can independently check google if you wish, it can be quite enlightening. Andy |
#50
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The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wymsey" wrote in message
... On Wed, 22 Oct 2014 19:17:38 +0100, gareth wrote: I didn't engage with them. I posted what I hoped to me a URL to useful material and they responded with infantile oubursts. If you ignore them all will be well and all manner of things will be well. It is important that real radio amateurs stand against the Childish Broadcasters (CBers) for the good of the future of amateur / ham radio. That there are a large number of such abusive individuals over in Yankland who subscribe to this NG must be of greater concern to the world of amateur radio. |
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