Home |
Search |
Today's Posts |
#11
![]() |
|||
|
|||
![]()
Yea...That's the ticket. Well, I figure he looked at the melted part and
said: "Gee, if I can keep this from melting..oh no... _WHY_ is it melting? ....perhaps high current. Yea, that's the ticket. There's high current in this part. I'll make it less lossy and it'll heat less and then the antenna'll be more efficient..... New technology, yea (;-). You can work Chile with a light bulb. As I say; "You need iron in the sky." PUBLISH and let the experts poke at it. My lot is 50' x 150' [155m x 460m outside the US] and I _very_ easily fit a 40M inverted Vee @35'. Work the world - several bands. There's a never ending quest for a number of physically unrealizable things including, but not limited to: a small, directive, high efficency antenna -- free power -- the "best" route to work -- the ideal mate...Yadda, Yadda I'll believe when... -- Steve N, K,9;d, c. i My email has no u's. "Tom Ring" wrote in message ... Oh come on, he said it's revolutionary! You are being way too judgemental. The melting probably had nothing to do with losses. I mean, it could have burst into flames due to corona igniting the revolutionary materials it was made of, and that's what melted it. Yeah, that's the ticket. tom K0TAR Tam/WB2TT wrote: An antenna that melts with 100W of RF going to it seems to be at odds with its claim of high efficiency. Tam/WB2TT |
#12
![]() |
|||
|
|||
![]()
"Chuck...K1KW" wrote in message news:0wNvc.39192$3x.31853@attbi_s54...
Anyone know anything about the "technology" in the article below? http://www.uri.edu/news/releases/?id=2659 Chuck...K1KW Article text below --------------------------------------------- Department of Communications/News Bureau 22 Davis Hall, 10 Lippitt Road, Kingston, RI 02881 Phone: 401-874-2116 Fax: 401-874-7872 ---------------------------------------------------------------------------- ---- URI physics employee invents new antenna technology Media Contact: Jan Wenzel, 401-874-2116 KINGSTON, R.I. -- June 2, 2004 -- Rob Vincent, an employee in the University of Rhode Island's Physics Department, proves the adage that necessity is the mother of invention. snip "According to current theory, you have to give up one of the three-size, efficiency, or bandwidth-to achieve any one of the other two." snip Is the above statement correct ? Regards Art5 |
#13
![]() |
|||
|
|||
![]() |
#14
![]() |
|||
|
|||
![]() Do you think the technology might be similar to the 160 meter indoor antenna called the TeslaVert? What a disservice to the great name of Tesla. Using loading coild to shorten the antenna and slap Tesla name on it to make "waves" in Antennex (BS) "magazine"? Yea spherical top is universe "invention". I got the copper toilet bowl float on the top of my vertical to prevent corona and add some top loading and broadbanding. Brace yourself for more "inventions" to come as we get flooded with more of un-knowledgeable hams. Hey, maybe there is a room to sell wunderantennas to idiots? I have 50 ohm DC to light 100% efficient, fits in a pocket miniature antenna for $100. (Secret? it is made by Ohmite) There is another one produced by GE or Phillips in China and it even provides light when power applied to it. You can use it as a lightbulb too. I will share my profits with US gubermint. Yuri, www.k3bu.us www.computeradio.us home of Dream Radio One |
#15
![]() |
|||
|
|||
![]()
"Chuck...K1KW" wrote in message news:0wNvc.39192$3x.31853@attbi_s54...
Anyone know anything about the "technology" in the article below? Ask him, he dunnit. http://www.qrz.com/detail/K1DFT w3rv http://www.uri.edu/news/releases/?id=2659 Chuck...K1KW Article text below |
#16
![]() |
|||
|
|||
![]()
That says that narrow bandwidth contributes to higher efficiency
which is how I always understood it.(Though many do not accept that) But as you say it is a shorthand type statement. My antenna on 160 is very narrow banded at any particular setting or frequency ( two loops and a short dipole coupled in tight cluster form),when modelled ,shows part of the current curve breaking out into a sino soidal oscillation (no phase change) for portions of the antenna. Such modelling, ofcourse, requires a large amount of points per unit length for high accuracy and the occillation would probably not show up visually if calculation points were reduced. It does not seem to affect things in practice on the air but I have often wondered what the consequences would be if the bandwidth was narrowed even more and the current oscillation possibly propagate over all the of the antenna ! With the current taking on an occillation it would suggest changes in radiation Art Richard Clark wrote in message . .. On 4 Jun 2004 10:44:01 -0700, (Art Unwin KB9MZ) wrote: "According to current theory, you have to give up one of the three-size, efficiency, or bandwidth-to achieve any one of the other two." snip Is the above statement correct ? Hi Art, In a crude and shorthand way, yes. This is why your small 160M vertical dipole is up to 15 to 17dB below performance in comparison to a full size one. All common legacy for CFAs, EHs, fractals, and the rest of this ilk that come down the pike. 73's Richard Clark, KB7QHC |
#17
![]() |
|||
|
|||
![]() |
#18
![]() |
|||
|
|||
![]()
snip
wrote: "According to current theory, you have to give up one of the three-size, efficiency, or bandwidth-to achieve any one of the other two." snip Is the above statement correct ? Hi Art, In a crude and shorthand way, yes. This is why your small 160M vertical dipole is up to 15 to 17dB below performance in comparison to a full size one. All common legacy for CFAs, EHs, fractals, and the rest of this ilk that come down the pike. 73's Richard Clark, KB7QHC Hmm I don't know where you are coming from but I ouldn't put my antenna in the CFA group that you state above. I know in the past that your antenna is better than mine which is O.K. but the fact is that many amateurs like to experiment and also pursue the "holy grail" Each attempt provide knowledge which is why antennas are pursued so much .I wager that the patent pending aproach discussed will provide welcome reading for everybody on this newsgroup. As for my particular antenna pursuit I am still not ready to throw it into the dustbin as every change provides new insights on antennas ( the sinosoidal current wave for one) I use my present antenna in the rotatable form on the top of the tower for convenience but I modelled it after reading your comments and they are as follows Top band....vertical orientation Impedance 349 +j41 ohms ( 186-j13 ohms when horizontally oriented on the tower) Load losses 2.88 db Efficiency 51.5% Radiation peak 23 degrees elevation -1.53dbi The above has bandwidth of around 5 Khz which is O.K. for audio, and frequency of use is selectable across the band. Since the feed point is at the center I don't have to tear up the lawn for those rotten radial wires. Efficiency jumps to over 90% on 80 meters and other bands with the typical figure eight form pattern, but my primary pursuit is on top band. Yes, the antenna can be beaten when following conventional design but the hunt using unconventional designs is part of the excitement, where slight change of inductance value moves you along the band /bands with out restriction with respect to power , the requirement of high voltage capacitors or large areas of grounding systems. My antenna may be regarded as 'useless' by many but, unlike the CFA and other antennas you placed me with, my antenna is in use and the impedances provided seem to match those given by modelling using a PRO antenna program and using maximum segments because of the UNCONVENTIONAL close coupled cluster design. Unconventional design provides insights to antennas like the oscillations that I refered to earlier, which is not to be seen on conventional designs and for which I seek further understanding and explanation. The new unconventional design from R.I. which is 'patent pending' no less may well provide further insights that we are unaware of. Unfortunately his efforts WILL be ridiculed by those who know that 'every thing about antennas is known' and by sharing he has shown his personal foolishnes to his peers. When will the amateur learn that it is a waste of time to experiment where the failures are heralded and the minutia of new facts are ignored ??? Please forgive me for writing this extra post which has strayed from my original post. Regards to all Art |
#19
![]() |
|||
|
|||
![]()
snip
wrote: "According to current theory, you have to give up one of the three-size, efficiency, or bandwidth-to achieve any one of the other two." snip Is the above statement correct ? Hi Art, In a crude and shorthand way, yes. This is why your small 160M vertical dipole is up to 15 to 17dB below performance in comparison to a full size one. All common legacy for CFAs, EHs, fractals, and the rest of this ilk that come down the pike. 73's Richard Clark, KB7QHC Hmm I don't know where you are coming from but I ouldn't put my antenna in the CFA group that you state above. I know in the past that your antenna is better than mine which is O.K. but the fact is that many amateurs like to experiment and also pursue the "holy grail" Each attempt provide knowledge which is why antennas are pursued so much .I wager that the patent pending aproach discussed will provide welcome reading for everybody on this newsgroup. As for my particular antenna pursuit I am still not ready to throw it into the dustbin as every change provides new insights on antennas ( the sinosoidal current wave for one) I use my present antenna in the rotatable form on the top of the tower for convenience but I modelled it after reading your comments and they are as follows Top band....vertical orientation Impedance 349 +j41 ohms ( 186-j13 ohms when horizontally oriented on the tower) Load losses 2.88 db Efficiency 51.5% Radiation peak 23 degrees elevation -1.53dbi The above has bandwidth of around 5 Khz which is O.K. for audio, and frequency of use is selectable across the band. Since the feed point is at the center I don't have to tear up the lawn for those rotten radial wires. Efficiency jumps to over 90% on 80 meters and other bands with the typical figure eight form pattern, but my primary pursuit is on top band. Yes, the antenna can be beaten when following conventional design but the hunt using unconventional designs is part of the excitement, where slight change of inductance value moves you along the band /bands with out restriction with respect to power , the requirement of high voltage capacitors or large areas of grounding systems. My antenna may be regarded as 'useless' by many but, unlike the CFA and other antennas you placed me with, my antenna is in use and the impedances provided seem to match those given by modelling using a PRO antenna program and using maximum segments because of the UNCONVENTIONAL close coupled cluster design. Unconventional design provides insights to antennas like the oscillations that I refered to earlier, which is not to be seen on conventional designs and for which I seek further understanding and explanation. The new unconventional design from R.I. which is 'patent pending' no less may well provide further insights that we are unaware of. Unfortunately his efforts WILL be ridiculed by those who know that 'every thing about antennas is known' and by sharing he has shown his personal foolishnes to his peers. When will the amateur learn that it is a waste of time to experiment where the failures are heralded and the minutia of new facts are ignored ??? Please forgive me for writing this extra post which has strayed from my original post. Regards to all Art |
#20
![]() |
|||
|
|||
![]() |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Inverted ground plane antenna: compared with normal GP and low dipole. | Antenna | |||
Mobile Ant L match ? | Antenna | |||
Poor quality low + High TV channels? How much dB in Preamp? | Antenna | |||
QST Article: An Easy to Build, Dual-Band Collinear Antenna | Antenna |