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The inefficiency of short antennae compared to long antennae, as previously discussed.
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. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 10/22/2014 5:13 AM, gareth wrote:
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. Obviously, none of this is new. It states in the article that the short antenna is inefficient due to the wire (ohmic) resistance swamping the radiation resistance. Your first post on this subject did not include wire resistance in your statement that short antennas are inefficient, which is why people jumped on that statement. If you include wire resistance, yes, a short dipole is less efficient that a full-sized dipole (if you can manage to get the power into it, which is a different problem). Note that a short antenna, properly constructed with, say, 4-inch copper pipe will be just about as efficient as one with #12 copper wire. Try it, please. Make the measurements. Record what you get and let us know. We are hungry for additional knowledge. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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? |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wayne" wrote in message
... 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? How are you going to deliver that 10 watts? By feeding with 100 Watts? |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 10/22/2014 10:05 AM, gareth wrote:
"Wayne" wrote in message ... 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? How are you going to deliver that 10 watts? By feeding with 100 Watts? Oops! Is that part of the problem? You never said matching was involved. Please get your story straight. Tell us your requirements. Using real wire? What diameter? What material? What length? Is feeding the antenna part of the problem? What the hell are you seeking? |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 10/22/2014 11:15 AM, John S wrote:
What the hell are you seeking? Drama -- Rick |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"gareth" wrote in message
... I despair that those who are motivated to shout out childish remarks continue to do so, even in the face of an informative post. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
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. -- Ian |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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? -- ;-) .. 73 de Frank Turner-Smith G3VKI - mine's a pint. .. http://turner-smith.co.uk |
The inefficiency of short antennae compared to long antennae, as previously discussed.
En el artículo , John S
escribió: What the hell are you seeking? 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. -- (\_/) (='.'=) (")_(") |
The inefficiency of short antennae compared to long antennae,as previously discussed.
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. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/14 16:15, John S wrote:
On 10/22/2014 10:05 AM, gareth wrote: "Wayne" wrote in message ... 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? How are you going to deliver that 10 watts? By feeding with 100 Watts? Oops! Is that part of the problem? You never said matching was involved. Please get your story straight. Tell us your requirements. Using real wire? What diameter? What material? What length? Is feeding the antenna part of the problem? What the hell are you seeking? He wants a row, as always. Why else is he hurling abuse and ignoring helpful posts? That is what he has always done. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
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. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/14 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. If you look in the uk.r.a archive going back to 1997 or so, long before I started posting, you will see he has been like this for decades. The only changes have been his sock puppets (a long list) and his prime targets. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On Wed, 22 Oct 2014 08:00:35 -0700, Wayne wrote:
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? Shirley it helps to keep the wire warm. -- M0WYM Sales @ radiowymsey http://stores.ebay.co.uk/Sales-At-Radio-Wymsey/ |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"gareth" wrote in message ... "Wayne" wrote in message ... 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? # How are you going to deliver that 10 watts? By feeding with 100 Watts? Perhaps 100 watts to the matching system. But, that's irrelevant to your theory. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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. But I^2 R losses are not part of the theory Gareth presented. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
In rec.radio.amateur.antenna gareth wrote:
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, You will get a Forbidden error. The home page is actually at: http://farside.ph.utexas.edu/teaching/em/lectures/ this leads to a most excellent revision of the necessary EM theories, and, briefly Just where has Fitzpatrick revised anything in EM theories? It all seems to be pretty standard stuff to me. -- Jim Pennino |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"John S" wrote in message
... In what way have I been abusive, Gareth? See below. It seems to me that you are a lost and lonely soul and are seeking some attention. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Brian Reay" wrote in message
... He wants a row, as always. Why else is he hurling abuse and ignoring helpful posts? That is what he has always done. You are the one who is hurling abuse. For example, all of your posts to this thread so far are personal attacks on me. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Brian Reay" wrote in message
... If you look in the uk.r.a archive going back to 1997 or so, long before I started posting, you will see he has been like this for decades. The only changes have been his sock puppets (a long list) and his prime targets. You're the one who is hurling abuse, repeatedly, into this thread. You need to learn that those who disagre with you are not being abusive not are they a problem of any sort. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Steve" wrote in message
... 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, Some will be radiated, but in a short antenna, much less than with a long antenna. That which is not radiated will reflect, or bounce off the end and arrive back at the feed point. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wayne" wrote in message
... But I^2 R losses are not part of the theory Gareth presented. You may think so, but I didn't give my inside leg measurement, either, nor did I discuss electron transport from one atom's orbit to another. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wayne" wrote in message
... Perhaps 100 watts to the matching system. But, that's irrelevant to your theory. So far, no-one has discussed what is NOT my theory, but established physics. |
The inefficiency of short antennae compared to long antennae,as previously discussed.
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'? -- Collecting Bitcoins for my Pension :) Please send BTC to 1kZKQMvVPce11u7xG1KbArtrAenuxdZue I thank you! |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"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 |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wymsey" wrote in message
... On Wed, 22 Oct 2014 16:38:08 +0100, gareth wrote: I despair that those who are motivated to shout out childish remarks continue to do so, even in the face of an informative post. The thing is, if you engage with people who don't like you then you will experience their dislike of you. If you ignore them all will be well and all manner of things will be well. Nobody here knows anything about me to dislike me. Discussing technical matters is not a matter of dislike. I didn't engage with them. I posted what I hoped to me a URL to useful material and they responded with infantile oubursts. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"gareth" wrote in message ... "Steve" wrote in message ... 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, Some will be radiated, but in a short antenna, much less than with a long antenna. That which is not radiated will reflect, or bounce off the end and arrive back at the feed point. If the short antenna is a dipole, then the two reflections will be considerably out of phase, resulting in vector cancellation, which will also contribute to reduced efficiency of radiation. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"gareth" wrote in message ... "Wayne" wrote in message ... But I^2 R losses are not part of the theory Gareth presented. # You may think so, but I didn't give my inside leg measurement, either, nor # did I discuss electron transport from one atom's orbit to another. Good, because those things are just as irrelevant as I^2 R to your theory. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Wayne" wrote in message
... "gareth" wrote in message ... "Wayne" wrote in message ... But I^2 R losses are not part of the theory Gareth presented. # You may think so, but I didn't give my inside leg measurement, either, nor # did I discuss electron transport from one atom's orbit to another. Good, because those things are just as irrelevant as I^2 R to your theory. Not MY theory, but established physics, as described in the URL in the OP |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On Wed, 22 Oct 2014 19:08:11 +0100, gareth wrote:
You need to learn that those who disagre with you are not being abusive not are they a problem of any sort. Oh, the irony. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
In message , No A1A
required writes 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'? If someone has a big nose, I would have thought that shouting "You've got a big nose!" at them would fairly be classed as 'abuse' (despite being true). -- Ian |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/2014 19:49, Ian Jackson wrote:
In message , No A1A required writes 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'? If someone has a big nose, I would have thought that shouting "You've got a big nose!" at them would fairly be classed as 'abuse' (despite being true). Indeed. However the comment was in reply to the paragraph above. This statement cannot be refuted. It's not abuse. -- Collecting Bitcoins for my Pension :) Please send BTC to 1kZKQMvVPce11u7xG1KbArtrAenuxdZue I thank you! |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Mike Tomlinson" wrote in message
... En el artículo , No A1A required escribió: How can the truth be 'abuse'? It meets *his* definition of abuse, just as he describes other posts as "grossly offensive" where no-one else would, including the judge at the trial where he was convicted of sending a malicious communication: Untrue The silly old fool has a remarkably thin skin for a troll, and like many cowardly trolls he can dish it out but can't take it. Untrue, and once again it is from you that the abuse originates. This article in the Register sums up the troll, Gareth Alun Evans, and his multiple personality defects, to a T: "Trolls are thought to possess a suite of nasty character traits called the "dark tetrad", which means they possess the charming combination of narcissism, sadism, Machiavellianism and psychopathy. This makes them vicious, manipulative, cruel, self-obsessed, abusive and quite possibly bananas." That would seem to be a good description of your mentally unhealthy obsession with me. old chap. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"Ian Jackson" wrote in message
... In message , No A1A required writes 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'? If someone has a big nose, I would have thought that shouting "You've got a big nose!" at them would fairly be classed as 'abuse' (despite being true). The difference there being that what is being shouted in an infantile manner above about me is not true. Review the number of times that tomlinson has appeared out-of-the-blue mouthing off at me, and muse as to where any mental problems might lie. |
The inefficiency of short antennae compared to long antennae, as previously discussed.
"No A1A required" wrote in message
... On 22/10/2014 19:49, Ian Jackson wrote: In message , No A1A required writes 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'? If someone has a big nose, I would have thought that shouting "You've got a big nose!" at them would fairly be classed as 'abuse' (despite being true). Indeed. However the comment was in reply to the paragraph above. This statement cannot be refuted. It's not abuse. Grow up, there, Not-Ham Hull, G7KUJ |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On Wed, 22 Oct 2014 19:49:25 +0100, Ian Jackson wrote:
If someone has a big nose, I would have thought that shouting "You've got a big nose!" at them would fairly be classed as 'abuse' (despite being true). So if I told Gareth he had a fat arse and a face like a bulldog chewing a wasp, it would be abuse? |
The inefficiency of short antennae compared to long antennae,as previously discussed.
On 22/10/2014 19:09, gareth wrote:
Some will be radiated, but in a short antenna, much less than with a long antenna. That which is not radiated will reflect, or bounce off the end and arrive back at the feed point. How might you modify that statement to deal with a situation where the "short antenna" is a quarterwave GP, and the long antenna is a three-quarterwave GP? |
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