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Guy from university physics ... Eureka! A picture!
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Guy from university physics ... Eureka! A picture!
On Fri, 22 Jun 2007 23:29:43 +0200, Jon Kåre Hellan
wrote: writes: On Jun 21, 10:26 pm, Richard Clark wrote: no one really reads these patnets do they? Not evne the author. Taken from top of Page 2 "Other publications" T. Simpson, "The Dick Loaded Monopole Antenna," IEEE Transactions of Antennas and Propagation, vol. 52, No. 2, Feb. 2004, pp. 542-545. Hardly worth going any further into the mysteries of this invention. Dipole envy? :-0 Abstract: http://ieeexplore.ieee.org/Xplore/lo...8/01282130.pdf It's "Disk loaded monopole" You didn't read the patent either, did you? ;-) I don't blame you. It is like reading the telephone book (aside from the obvious sloppiness). 73's Richard Clark, KB7QHC |
Guy from university physics ... Eureka! A picture!
On Jun 22, 4:07 pm, John Smith I wrote:
wrote: ... I've already done the experiments.. Going on nearly 20 years ago.. I'm just telling what I see in the pix.. Yes, but then you didn't see what Mr. Vincent "seen", enough to get a physics dept. of a university to back him, and mentioned by arrl! And, gawd knows, arrl is a power to be recognised! COUGH! Doesn't matter to me. I don't build my antennas for the ARRL. I build them for me... I'm not even a member of the ARRL.. Never have been. But then, the naysayers have painted Mr. Vincent as a con man, indeed, not just a "con man" but a "SUPER CON MAN!" The type of con man where bankers lock their doors at his approach, men step before their wives in protection, wives shade the eyes of their children, massive and powerful men grasp their wallets tightly and expert con men run before him in fear, envy and loathing! :-( I don't think he's a con man at all. But I don't think the information he provides give anyone enough info to make an accurate comparison. Or at least from what I've seen. There is nothing really "wrong" with his antenna. I just think there are better ways to get what he is after, which seems to be mainly improved current distribution. People have known how to improve the current distribution for years.. Nothing new.. And it sure does not require multiple loading coils to accomplish. His disks? Nothing more than small capacitive hats.. Nothing new there. I just don't see the hype, and in fact, I think his design would end up being inferior to what I would cook up for the same height mast and stinger. Cecil seems to agree with me, so if you don't believe me, maybe his word will mean a little more to you. The *best* way to load a short vertical is with a large enough capacity hat to load the antenna with *no* loading coil needed. And that is what your's truly would build if I had to have a contest against his using the same height whip. And the current distribution in such a case is pretty linear across the whole whip. You ain't gonna beat that with a bunch of multiple coils, disks, linear loading, etc, ad nausium.. But if you want to try, be my guest.. MK |
Guy from university physics ... Eureka! A picture!
On Jun 22, 5:32 pm, wrote:
The *best* way to load a short vertical is with a large enough capacity hat to load the antenna with *no* loading coil needed. And that is what your's truly would build if I had to have a contest against his using the same height whip. BTW, I realize if the antennas were for a low freq, I might have to use a coil in order to avoid a hat that was just too big to handle, but still, I would concentrate as much capacitive loading at the top as I could, and use the minimum inductor value to match the antenna. If we both have to use coil loading, mine should win. The current distribution will be more linear on mine. And in a case using a large hat, it really doesn't matter where the coil is. The current distribution will still be fairly linear as long as the hat is big enough. That would be about the only case where I might consider a base loading coil to reduce coil windings. MK |
Guy from university physics ... Eureka! A picture!
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Guy from university physics ... Eureka! A picture!
On Jun 22, 5:56 pm, John Smith I wrote:
wrote: [stuff] Yes, it is duly noted that you would repeat what has been done before ... However, we ALL know where that gets one, don't we? Regards, JS I think it would give me the better antenna in this case. I doubt he would want me at one of his seminars.. I'd be one of those hecklers that he has nightmares about late at night. But in my case, I would whip out my antenna and whoop him right there on the spot if he was brave enough to compare. I repeat what is proven to be best. I've already tried all his methods, and proven them inferior by testing. I'll back up my jibber jabber with real working antennas. Would be simple to set up too.. All I need is a standing mast like yours, and a few wires to string out a large top hat. I wonder what his alphabet soup would buy him if he lost... :/ MK |
Guy from university physics ... Eureka! A picture!
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Guy from university physics ... Eureka! A picture!
John Smith I wrote:
[stuff] Actually, I don't think I explained that well--for want of a better explanation ... Take the Michelson–Morley experiment. They were attempting to find the equivalent of how the doppler effect affects sound in air. However, if the way matter affects ether is similar to the way air affects sound, the earth and its' atmosphere would be a less than optimal test bed. Indeed, if you take the horn from a train and place it in a long train, you would loose the effect, the skin of the train deflects/slows/distorts/whatever the air which causes the effect. Now, if someone where to reconstruct the Michelson–Morley experiment from the nose of a space shuttle (no matter intervening or massive matter in close proximity), to mirrors traveling at the same speed and in the same trajectory of the shuttle, perhaps a quite different conclusion would be reached. Especially, if the matter of air and proximity to earth is masking anything enough to throw off the experiment. I know unexpected results were obtained when a long tether was let out behind the shuttle, and never explained to my satisfaction. Perhaps that is a somewhat better way to express what I attempted in the post this one responds too ... Regards, JS |
Guy from university physics ... Eureka! A picture!
On 22 Jun, 17:21, John Smith I wrote:
wrote: [stuff] In countless physics labs, around the world, students complete experiments done countless times before--and this is good ... it is hoped, one day, they go on to complete experiments never done before, or even ones not done properly, or those were important data was missed ... That is simply all I point out ... an open mind never knows for certain. Regards, JS He has done everything to do with antennas. He has also read the WWW from beginning to the end, nothing new he has done it all. I would imagine that the antenna company that he designed antennas for gave up and went bankrupt when he said he was going to retire. I would imagine that is why the space ship landed today in California no point in taking risks now that he has left. IEEE is looking for an experienced antenna designer with extensive knoweledge of all types of antennas with extensive experience in determining worthwhile projects and be able to smell those that would fool others. Must be able to provide evidence of achievements that have benefited the advance of science. Experience in winding coils accepted as well as evidence of climbing towers to replace light bulbs. Must be a EE with a Masters from an accredited college with a history of writing papers on the science of antennas as well as able to judge antenna designs presented to the IEEE. Trench diggers for cable installations need not apply. Maybe he will not be around to long as he is evidently better than sliced bread in all the sciences. I imagine that he made more money on the stock market than the average broker |
Guy from university physics ... Eureka! A picture!
art wrote:
[stuff] Well, it is good to remember, the boys in R&D (the ones who come up with the new stuff) get paid just as much to find out what doesn't work, as the do to find the stuff which does ... It is the ratio of the two which determines if they keep their jobs or not ... well, unless they work for gov't ... Regards, JS |
Guy from university physics dept. makes claims to incite/provoke amateurs!
Ian Jackson wrote in
: In the UK, amateur 'hamfests' and 'tailgate sales' used to be a fairly leisurely affair, starting at a round 11am, and go on until 5 or even 6pm, allowing lots of time to wander around, meet your long-lost friends etc (ie a 'good day out'). These days, opening time is often as early as 9am, with some dealers starting to pack up around noon. Ordinary tailgate sales sometimes do start at early as 7am. Things ain't what they used to be. Yoiks! If they only started at 9 a.m. here... Just possibly, there is a glimmer of hope. I have noticed that in the past year a lot of the computer junk has gone away - do we really need that Pentium 1 computer? (hint, the answer is no) Perhaps this will return the hamfests to hams, and we can enjoy chatting and socializing again, as well as selling our own "junk" - 73 de Mike KB3EIA - |
Guy from university physics ... Eureka! A picture!
On Jun 22, 7:33 pm, art wrote:
On 22 Jun, 17:21, John Smith I wrote: wrote: [stuff] In countless physics labs, around the world, students complete experiments done countless times before--and this is good ... it is hoped, one day, they go on to complete experiments never done before, or even ones not done properly, or those were important data was missed ... That is simply all I point out ... an open mind never knows for certain. Regards, JS He has done everything to do with antennas. Nope.. But I've tried nearly every perversion of a short vertical you can conjer up.. I bet a lot more than you have. I tried the methods that guy is using a long time ago. Do you think I should ignore all results of the tests I do? If his methods were best, don't you think I would have one mobile? He has also read the WWW from beginning to the end, Not yet, but I have road runner cable now. I'm working on it at a bit faster clip now... nothing new he has done it all. I haven't molested Paris Hilton yet... But, actually, she's really not my type.. I don't really like whiny bitchettes... I would imagine that the antenna company that he designed antennas for gave up and went bankrupt when he said he was going to retire. And what company might that be? I would imagine that is why the space ship landed today in California no point in taking risks now that he has left. If that's what you imagine, then you are fairly clueless. IEEE is looking for an experienced antenna designer with extensive knoweledge of all types of antennas with extensive experience in determining worthwhile projects and be able to smell those that would fool others. I already have a job.. But maybe I could consult for them part time. I can usually smell male bovine droppings from a fairly good distance. Must be able to provide evidence of achievements that have benefited the advance of science. I'll show mine, if you show yours... Experience in winding coils accepted as well as evidence of climbing towers to replace light bulbs. I can wind a coil, but I've never climbed a tower to change a light bulb. I would like to try it, but access to the local antenna farm is fairly restricted. Mainly due to liability, insurance purposes. BTW, I'm not an aggie... Does that give me extra light bulb changer status? Must be a EE with a Masters from an accredited college I'll get mine when you get yours... with a history of writing papers on the science of antennas as well as able to judge antenna designs presented to the IEEE. Sounds like a boring job.. I've decided I'll pass.. I'd rather fly a Southwest 737 than do something as sleep inducing as that. Trench diggers for cable installations need not apply. I've never worked for the cable company, but like I say, I do have road runner cable now. But our system is fiber optic, overhead lines, etc.. No trenches around here. But playing in the dirt does kind of appeal to me. Maybe he will not be around to long as he is evidently better than sliced bread in all the sciences. If I'm not around *too* long, it's probably cuz I puff too many cig's and drink about 22 cups of coffee a day.. You can see me hard at work here... http://web.wt.net/~nm5k/nm5k.jpg I imagine that he made more money on the stock market than the average broker You really wonder about stuff like that? You must really be bored... If I were your doktor, I would recommend two prozac, and call me monday morning, at which time I'll consider a lobotomy if you haven't improved by then. MK |
Guy from university physics ... Eureka! A picture!
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Guy from university physics ... Eureka! A picture!
wrote in message ups.com... On Jun 22, 5:32 pm, wrote: The *best* way to load a short vertical is with a large enough capacity hat to load the antenna with *no* loading coil needed. And that is what your's truly would build if I had to have a contest against his using the same height whip. BTW, I realize if the antennas were for a low freq, I might have to use a coil in order to avoid a hat that was just too big to handle, but still, I would concentrate as much capacitive loading at the top as I could, and use the minimum inductor value to match the antenna. If we both have to use coil loading, mine should win. The current distribution will be more linear on mine. And in a case using a large hat, it really doesn't matter where the coil is. The current distribution will still be fairly linear as long as the hat is big enough. That would be about the only case where I might consider a base loading coil to reduce coil windings. MK I thought the base coil would be for impedance matching, maybe he is tapping up on the coil to find a 50 ohm point. |
Guy from university physics ... Eureka! A picture!
On 23 Jun, 07:44, John Smith I wrote:
wrote: ... Well, it appears to me, the shortened 10 meter 1/2 is superior to a 1/4 (both mounted mobile) and the shortened 1/2 is VERY close in performance to a full ~17 ft. (vs. ~5.3 ft. shortened--with the top hat and spacings optimized, the difference is less than the width of a meter needle.) This silly combination of know "tricks" is certainly doing something which common place formulas/equations don't account for ... However, if you already naysay on the navy data, I won't be able to present any proof which even comes close--my equipment budget doesn't even begin to match that of the navys' to begin with ... JS, I would say that your results are significant assuming you used the same ground plane. Given the tolerances involved and knowing that the human ear would not be able to discern the difference I think you have provided enough even for the poorest naysayer to cogitate upon. They could say I misunderstood I suppose To bring down the antenna length as much as you have without a discernable difference will certainly gain attention from mobilers. After all I doubt that any of them considered competing with a testing station with respect to a ground plane. Well done Art Too bad a bunch of different people don't use a standard test jig, apply their own modifications and generate a ton of data/results ... Regards, JS |
Guy from university physics ... Eureka! A picture!
Jimmie D wrote:
... I thought the base coil would be for impedance matching, maybe he is tapping up on the coil to find a 50 ohm point. That is exactly the way I interpreted his description/pics; and, it's exactly the way I implemented it (a modified gamma match--implemented in helix form?) The wire-length/inductance is a 1:1.4 ratio between bottom helix and upper loading coil--with the 1.4 of the length in the upper loading coil. An adjustable 20" length of conductor is used between lower and upper coils. Top whip is a 20" length also. (10 meter design) From what I estimate, it ended up using, VERY CLOSE! TO, a computed half-wavelength of wire at 28.050! And, I mean within' 1-3 inches! I honestly did not expect that ... Tap ended up almost dead center in the bottom helix turns for a 50 ohm match; a variable capacitor is in series with this tap point on the bottom helix and used to tune out the inductance of the tap wire. I kludged a var/cap together using two small sheets of light aluminum. These sheets are rolled into tubes and made so one is a smaller dia and slips very loosely into the one of a larger dia. I then cut some clear plastic from a drink container, rolled it and use it as the dielectric (withstands the 1-100 watts test signal) between the inner/outer tubes. This makes a serviceable/usable var. concentric cap. Inner tube is roughly the dia of a bic pen (~1/4 inch.) #8 copper is used, except for the upper loading coil which is #10 copper. Try one; prove me wrong; I dare ya! Regards, JS |
Guy from university physics ... Eureka! A picture!
On Jun 23, 8:44 am, John Smith I wrote:
wrote: ... Well, it appears to me, the shortened 10 meter 1/2 is superior to a 1/4 (both mounted mobile) and the shortened 1/2 is VERY close in performance to a full ~17 ft. (vs. ~5.3 ft. shortened--with the top hat and spacings optimized, the difference is less than the width of a meter needle.) I assume you mean winding a 1/2 wave winding on a short stick. I could see that maybe beating a 1/4 wave if the ground system was not the greatest.. But I don't really see it happening over a good ground, where the 1/4 wave isn't really stunted. It's quite possible for for a 1/4 wave whip on a bumper, to lose to a loaded whip half it's size, if mounted on the roof. So on a car/truck, the location can make a big difference.. CB'ers have run those things for years under various names. I can see cases with lousy grounds where a 1/2 wave, even short might be worth a try. But I once did a comparion with my standard "1/4 wave tuned" mobile on 15m, vs using my 40 meter setup on 15m as a "extended winding" psuedo 5/8 wound whip. The normal 1/4 wave setup was the best. This silly combination of know "tricks" is certainly doing something which common place formulas/equations don't account for ... Ground, or lack of it could account for it. Same mount location, etc? Bumper, trunk, or roof? A mobile is not the best place to test vertical antennas. Too quirky...The car is half the antenna. Sure, you can see which one works best, but it's not a very good test platform in general. I'd rather test over a specified quantity of radials, if ground mounted. Ditto for elevated, the only difference being the number required drops as you increase height. However, if you already naysay on the navy data, I won't be able to present any proof which even comes close--my equipment budget doesn't even begin to match that of the navys' to begin with ... I don't know what navy data you are talkng about. Too bad a bunch of different people don't use a standard test jig, apply their own modifications and generate a ton of data/results ... I don't know what you mean by "test jig".. What you have as far as a "test" antenna, or having a location with a specified ground quality? MK |
Guy from university physics ... Eureka! A picture!
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Guy from university physics ... Eureka! A picture!
John Smith I wrote:
... Anyway, in a relatively short period of time I should have expended all my energy and ideas and know this antenna inside out--probably just a couple of months or so ... This time I am chucking all "laws" and just experimenting, I will especially be trying things which "don't work!, and run contrary to "accepted practices." Regards, JS |
Guy from university physics ... Eureka! A picture!
On Jun 24, 8:51 pm, John Smith I wrote:
Frankly, I think the high performance standard of mobile antennas has just changed when small size and stealth are of importance ... Sorry if I don't hold my breath waiting for this miracle to happen.. :/ MK |
Guy from university physics ... Eureka! A picture!
On 24 Jun, 19:51, John Smith I wrote:
wrote: ... snip. I am just disappointed that the patent system allows a rearrangement of already and quite commonly known/implemented designs/methods/practices to be patented; as far as I am concerned, all this should be considered to be in the public domain ... Regards, JS I don't see it that way. He tried something that all denied would work. If he had not tried it we would still be on existing equipment. If this works as suggested the frontier of antenna design has moved a long distance forward providing a new platform from which to start on the next discovery. We have had decades to improve antenna whips without success now because of the inquisivity of one person who was not to be deterred by couch naysayers, we now have a larger group of experimentors that are willing to experiment to look for something new. Doesn't sound to bad to me for the hobby. Probably has uses in WiFi and embedded antennas. |
Guy from university physics ... Eureka! A picture!
art wrote:
... I don't see it that way. He tried something that all denied would work. ... Art: Your view is certainly arguable ... it is difficult to take up a defense-able stand on either side of the worth of this patent--in my humble opinion ... however, I have no horse in the race. Regards, JS |
Guy from university physics ... Eureka! A picture!
Try one; prove me wrong; I dare ya! Regards, JS I don't see where the "inventor" of the DLM style antenna has violated any laws of physics... He has simply found the sweet spot of mixed C & L and short straight radiating sections along a shortened antenna to pull it into resonance while maintaining a a flatter SWR curve... With the helical lower section if that is how it is actually functioning also acting as an auto transformer he simplifies the matching of the feed point to coax... Sevick proved that shortened antennas can work well... If you look at the Fisher Island data for the DLM it shows that the gain of the antenna improves considerably with top loading - a finding we would definitely expect in a shortened monopole... Authors from Sevick, to Cebik, to W8JK, to W8JI, have championed the benefits of top hats for short antennas... BTW, we have the oposite end of the spectrum in the distributed capacity antenna with multiple caps along the length to redistribute current peaks... So using capacitive reactance to redistribute current along the antenna is well known and documented... All in all, it sounds like a fun antenna, John... The guys really ought to be looking at this as a method of trimming 160 and 80 verticals to a more manageable size while retaining some bandwidth and having easy matching... If I didn't already have full size antenna arrays for these bands I would be out there building one to see how it performs... I would hope that all those posting on the topic have read all the URL's provided - and also noted the point that the antenna benefits from being elevated and having elevated radials to work against , even whilst mounted over the excellent ground plane of the Navy's test range - a major piece of information...... denny / k8do |
Guy from university physics ... Eureka! A picture!
Denny wrote:
... All in all, it sounds like a fun antenna, John... The guys really ought to be looking at this as a method of trimming 160 and 80 ... denny / k8do Denny: I already like 'ya more than I did yesterday; This is why we got into amateur radio, isn't it?; How come so many seem to have forgotten? Warm regards, JS |
Guy from university physics dept. makes claims to incite/provokeamateurs!
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Guy from university physics ... Eureka! A picture!
"Denny" wrote in message oups.com... Try one; prove me wrong; I dare ya! Regards, JS I don't see where the "inventor" of the DLM style antenna has violated any laws of physics... He has simply found the sweet spot of mixed C & L and short straight radiating sections along a shortened antenna to pull it into resonance while maintaining a a flatter SWR curve... With the helical lower section if that is how it is actually functioning also acting as an auto transformer he simplifies the matching of the feed point to coax... Sevick proved that shortened antennas can work well... If you look at the Fisher Island data for the DLM it shows that the gain of the antenna improves considerably with top loading - a finding we would definitely expect in a shortened monopole... Authors from Sevick, to Cebik, to W8JK, to W8JI, have championed the benefits of top hats for short antennas... BTW, we have the oposite end of the spectrum in the distributed capacity antenna with multiple caps along the length to redistribute current peaks... So using capacitive reactance to redistribute current along the antenna is well known and documented... All in all, it sounds like a fun antenna, John... The guys really ought to be looking at this as a method of trimming 160 and 80 verticals to a more manageable size while retaining some bandwidth and having easy matching... If I didn't already have full size antenna arrays for these bands I would be out there building one to see how it performs... I would hope that all those posting on the topic have read all the URL's provided - and also noted the point that the antenna benefits from being elevated and having elevated radials to work against , even whilst mounted over the excellent ground plane of the Navy's test range - a major piece of information...... denny / k8do I agree, this is just nothing new. As you say Jerry Sevick has already been thier and done that. Jery already has established that making a short antenna is no big deal as long as you have a good ground system and a low loss matching network How well Vincents antenna performed has more to do the the excellent ground system used in the test than anything special about the antenna.. Jimie |
Guy from university physics dept. makes claims to incite/provoke amateurs!
On Jun 25, 11:12 am, John Smith I wrote:
John Smith I wrote: ... A DLM by unknown builder:http://assemblywizard.tekcities.com/dlm.jpg JS Exactly like the mobile antennas I use to run.. In fact, still have one of them in that basic config.. I didn't use the "metal mast" that runs along the glass part above the coil. I used the wire from the glass whip itself. The original antenna was a 5 ft glass CB antenna. In it's reworked condition, it's 10 ft long, if I use the 5 ft stinger. But on the higher bands, the coil is totally bypassed, and the tuning is done by changing stinger length. It works all bands 80-10. But my new improved version does not use any helical windings on the glass whip. I stripped them all off, and only use a large lumped coil at the top of the glass whip. My present version was built from a 6 ft 20m hamstick which I butchered up. It's total height is 11 ft, and it also works all bands. It's the better antenna of the two. BTW, I also have a 3 ft hustler mast which I can add to the base of either one of those. Lengthens the mast 3 more feet under the coil, and makes a large increase in efficiency. I use it when parked. MK |
Guy from university physics ... Eureka! A picture!
Jimmie D wrote:
... I agree, this is just nothing new. As you say Jerry Sevick has already been thier and done that. Jery already has established that making a short antenna is no big deal as long as you have a good ground system and a low loss matching network How well Vincents antenna performed has more to do the the excellent ground system used in the test than anything special about the antenna.. Jimie You must realize that you are either severely mentally disabled, of a liar of monumental effort! If not, don't worry, the rest of us do ... JS |
Guy from university physics dept. makes claims to incite/provokeamateurs!
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Guy from university physics dept. makes claims to incite/provoke amateurs!
On Jun 25, 12:36 pm, John Smith I wrote:
wrote: ... Huh! And, you didn't even realize the rest of us were only getting about 50% efficiency of a full size antenna, out of our shortened? (vs. the 98% Vincents seems to be!) Too bad, you could have shared back with us then and looked like a superstar--instead of a fibber! Oh well, I am sure you will be "right on it" next time ... JS Fibber? Where do you come up with this BS..Do you want me to take a picture of it? Crap, you better get your head out of your kazoo if you want me to talk to you. I give you the benefit of the doubt by even discussing it with you, but you start your usual smart ass remarks, and basically pull a "Telemon".. I don't need to prove anything to you. I could care less really. My mobile antenna is as good as it can be, for the physical restraints, and it got to that point at least 3-4-5 years ago.. I'm not going to run a hat on my mobile, and I accept that loss in performance. That why I run a long 5 ft stinger whip. I don't feel the need to "reinvent" stuff and be a radio superstar. I have better things to do with my time. 98% efficient? Over what ground? Have they compared to a fully top loaded vertical? A coax fed dipole is about 98% efficient.. :/ Must be one heck of a radial system is all I can say.. What does this look like on the back of that truck? http://web.wt.net/~nm5k/fd3.jpg I got your fibber hanging.. That antenna started out as a 6 ft 20m hamstick I got for free. But I used it on 40m, by adding a 5 ft stinger. Worked very well overall. Then I stripped all the windings off and installed the larger coil you see in the picture. The other 5 ft version I have is the same , except it's coil is mounted about 2.5 feet above the base, instead of 5, and the helical windings at the base, and even some above the large coil are still intact. The antenna works quite well. But my antenna with no helical windings is more efficient. But thats more due to coil location, than less efficient coil loading. I don't know who you think you are, but I was doing what you are doing now, in 1988. That's when I built that partly helical "plastic bugcatcher". Many others were doing the same in 1958 I'm sure... If I had a digital camera handy, I'd already have a picture waiting for you. You can tell by looking at it, I've used it for years on end. It's about 19 years old, and has thrashed many a tree branch. I play mainly on 80 and 40 meters mobile. Go do some testing there, and get back to me. This 10m testing on a mobile doesn't mean too much to me.. It's easy to get high efficiency on that band. Most any "wonderstick" will do. Lets see this thing kill on 80m where the likelyhood of ground loss overiding the coil loss kicks into play. The low bands are the real test of a short vertical. I saw one mention that elevating this antenna will improve the performance. Heck, elevating most any kind of vertical or GP will improve performance.. That antenna is not special in that regard.. It really surprises me that you seem to think this is some kind of new technology.. What, you live in a cave? MK |
Guy from university physics dept. makes claims to incite/provokeamateurs!
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Guy from university physics dept. makes claims to incite/provoke amateurs!
wrote in message ups.com... On Jun 25, 12:36 pm, John Smith I wrote: wrote: ... Huh! And, you didn't even realize the rest of us were only getting about 50% efficiency of a full size antenna, out of our shortened? (vs. the 98% Vincents seems to be!) Too bad, you could have shared back with us then and looked like a superstar--instead of a fibber! Oh well, I am sure you will be "right on it" next time ... JS Fibber? Where do you come up with this BS..Do you want me to take a picture of it? Crap, you better get your head out of your kazoo if you want me to talk to you. I give you the benefit of the doubt by even discussing it with you, but you start your usual smart ass remarks, and basically pull a "Telemon".. I don't need to prove anything to you. I could care less really. My mobile antenna is as good as it can be, for the physical restraints, and it got to that point at least 3-4-5 years ago.. I'm not going to run a hat on my mobile, and I accept that loss in performance. That why I run a long 5 ft stinger whip. I don't feel the need to "reinvent" stuff and be a radio superstar. I have better things to do with my time. 98% efficient? Over what ground? Have they compared to a fully top loaded vertical? A coax fed dipole is about 98% efficient.. :/ Must be one heck of a radial system is all I can say.. What does this look like on the back of that truck? http://web.wt.net/~nm5k/fd3.jpg I got your fibber hanging.. That antenna started out as a 6 ft 20m hamstick I got for free. But I used it on 40m, by adding a 5 ft stinger. Worked very well overall. Then I stripped all the windings off and installed the larger coil you see in the picture. The other 5 ft version I have is the same , except it's coil is mounted about 2.5 feet above the base, instead of 5, and the helical windings at the base, and even some above the large coil are still intact. The antenna works quite well. But my antenna with no helical windings is more efficient. But thats more due to coil location, than less efficient coil loading. I don't know who you think you are, but I was doing what you are doing now, in 1988. That's when I built that partly helical "plastic bugcatcher". Many others were doing the same in 1958 I'm sure... If I had a digital camera handy, I'd already have a picture waiting for you. You can tell by looking at it, I've used it for years on end. It's about 19 years old, and has thrashed many a tree branch. I play mainly on 80 and 40 meters mobile. Go do some testing there, and get back to me. This 10m testing on a mobile doesn't mean too much to me.. It's easy to get high efficiency on that band. Most any "wonderstick" will do. Lets see this thing kill on 80m where the likelyhood of ground loss overiding the coil loss kicks into play. The low bands are the real test of a short vertical. I saw one mention that elevating this antenna will improve the performance. Heck, elevating most any kind of vertical or GP will improve performance.. That antenna is not special in that regard.. It really surprises me that you seem to think this is some kind of new technology.. What, you live in a cave? MK Seems like I have seen a lot of Ham STIKS lately that were use to construct homebrew antennas. Jimmie |
Guy from university physics dept. makes claims to incite/provoke amateurs!
On Jun 25, 6:31 pm, "Jimmie D" wrote:
Seems like I have seen a lot of Ham STIKS lately that were use to construct homebrew antennas. Jimmie They are good for tinkering with, and they are cheap. A hamstick on it's own can be a real good antenna as is if you modify it to work on a lower band by adding a longer stinger. Some brands vary though. Some have semi decent length stingers from the factory, and some are real short, or have no stinger. Those are the worst. The one in the picture was a 6 ft 20 meter stick which had no real stinger on it. It was pretty lame on it's designed band. But I added a 5 ft stinger and used it for 40m. Worked quite well on the trunk of my car. Almost bugcatcher level performance with no large lumped coil. So if one were to want to use a hamstick for a mobile, they are better off to buy one for a higher band, and then clamp various stingers to work the lower bands. It will be more efficient than the sticks actually sold for those lower bands. IE: my original antenna which John Smith seems to think I've made up in my mind, was a CB antenna originally. A firestick I think.. I got it free too.. I've never spent a dime on any of my mobile antennas... Well, except for wire in some cases. I added the coil to work 80 and 40. But on 20-10, I just used various lengths of stinger, and the coil was bypassed with a jumper. That antenna on 20m, is better than most that are sold for 20m.. :/ More stinger, and less windings.. Also the methods of windings can effect current distribution. The better versions wind more coil up high, as to resemble a lumped coil in that location. This improves current distribution same as it would with a normal lumped coil.. Many of the sticks have a winding at the base just for matching. But the matching portion can be included with the main lumped coil too. It doesn't have to be at the base. But my latest version has no helical windings. Just the large coil. It's pretty much purely a "plastic bugcatcher".. MK |
Guy from university physics dept. makes claims to incite/provoke amateurs!
John Smith I wrote: A DLM by unknown builder: http://assemblywizard.tekcities.com/dlm.jpg I saw the picture. It looks like a coil base not much unlike the ham-stick, then a piece of wire back to ground, presumably a match, above the helical, is a piece of brass or copper wire, then a regular loading coil, and another piece of brass or copper for the stinger. It doesn't sound like the descriptions I am hearing. -- 73 for now Buck, N4PGW www.lumpuckeroo.com "Small - broadband - efficient: pick any two." |
Guy from university physics dept. makes claims to incite/provokeamateurs!
Buck wrote:
... It doesn't sound like the descriptions I am hearing. Buck: Take a look at the patent. You have to create an account to view it, the account is free: http://www.freepatentsonline.com/7187335.html Regards, JS |
Guy from university physics dept. makes claims to incite/provokeamateurs!
Buck wrote:
... It doesn't sound like the descriptions I am hearing. Hopefully, this URL will take you right to a schematic of the antenna: http://tinyurl.com/2tqon2 JS |
Guy from university physics dept. makes claims to incite/provoke amateurs!
On Tue, 26 Jun 2007 11:44:13 -0700, John Smith I
wrote: Buck wrote: ... It doesn't sound like the descriptions I am hearing. Hopefully, this URL will take you right to a schematic of the antenna: http://tinyurl.com/2tqon2 JS The section below with pictures made a difference. I saw that the patent is in concept, that is the arrangement of the coils for the desired effect and the design of coils which can be helical, squared off, etc. Thanks. Buck -- 73 for now Buck, N4PGW www.lumpuckeroo.com "Small - broadband - efficient: pick any two." |
Guy from university physics dept. makes claims to incite/provokeamateurs!
Buck wrote:
... The section below with pictures made a difference. I saw that the patent is in concept, that is the arrangement of the coils for the desired effect and the design of coils which can be helical, squared off, etc. Thanks. Buck Buck: Yeah, all that alright. However, he also claims the "arrangement" he has increases the impedance of the 1/4 wave shortened antenna to 72-100 ohms. This is interesting in and of itself, shortened antennas tend to have impedances in the single digits and are difficult to match efficiently ... I am just beginning to toy with this version, maybe can get serious this weekend ... Regards, JS |
Guy from university physics dept. makes claims to incite/provoke amateurs!
On 26 Jun, 13:34, John Smith I wrote:
Buck wrote: ... The section below with pictures made a difference. I saw that the patent is in concept, that is the arrangement of the coils for the desired effect and the design of coils which can be helical, squared off, etc. Thanks. Buck Buck: Yeah, all that alright. However, he also claims the "arrangement" he has increases the impedance of the 1/4 wave shortened antenna to 72-100 ohms. This is interesting in and of itself, shortened antennas tend to have impedances in the single digits and are difficult to match efficiently ... I am just beginning to toy with this version, maybe can get serious this weekend ... Regards, JS John, I know nothing about vertical whips and I haven't been following the whole thread but it does come to mind that the aperture, which is related to gain, appears to be determined by the smallest diameter drawn that can include the antenna physical configuration. Ofcourse to do this is to have the largest capacity hat as possible with the minimum wire resistance wire that obtains the highest resistance(coil windings) meaning that even if the actual resistance is high so is the radiation resistance. All these factors are varying in curve form ( See Terman for typical curves of all variables) so you may get some insight on what is really happening by reviewing the cross over points of some of these curves relative to the diameter of the capacity hat. Take all of this with a pinch of salt but the answer may well be there some where when looking for the size of the aperture. Regards Art |
Guy from university physics dept. makes claims to incite/provokeamateurs!
art wrote:
... but it does come to mind that the aperture, which is related to gain, ... Regards Art Yes Art, this IS the most perplexing of all ... the aperture ... How can you reduce an antenna with a "capture" of 1, to a "capture" of ..3333333 and not suffer a signal loss of related proportions. I ponder this. Regards, JS |
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