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"Ian White, G3SEK" wrote in message ... Jack Painter wrote: "Richard Clark" wrote So much of this breathless science of rounded tips alludes to the legitimacy of rare publications equal in scope and stature to those that announced the proofs of cold fusion. Did Pons and Fleishman turn their hands to designing Lightning protection systems to redeem their credentials? Interested in your comments *after* you have read the study. http://lightning-protection-institut...-terminals.pdf Yes, let's have more technical discussion and less name-calling, please. There seem to be three observations that need to be understood. 1. The electric field gradient near a sharp point is greater than the field gradient near a blunt point. This is basic physics and should be completely beyond dispute. But that is the field gradient IMMEDIATELY LOCAL to the point... and that's not what lightning protection is about. I would think that lightning protection should begin with the safe equalization of charges. If one could prevent localization of charge, there wouldn't be anything to discharge. Failing that, if one could provide a controlled discharge mechanism, that drains charge without a massive discharge channel, that would also be good. Failing that, you fall back to a point g defense; first dissuading the creation of a conductive channel to the protected area, or, failing at that, providing a specific, perhaps sacrificial path for the massive discharge. The first methods, involving charge management, might be effected by controlling the conductivity of the air. Chemical and mechanical methods seem difficult to deploy and might not be able to affect sufficient volume. I wonder if conductive air volumes, or specific channels, might be created by RF stimulation? Might it be possible to map the atmospheric charge, and through an array of steerable microwave exciters, create specific conductive paths for the relatively safe dissipation of localized charge? I wonder if the HAARP has investigated lightning control possibilities? Ed wb6wsn |
Ed Price wrote:
I would think that lightning protection should begin with the safe equalization of charges. Oh, how we all wish! But think what that implies... If one could prevent localization of charge, there wouldn't be anything to discharge. That would require control over the weather - and again, oh how we all wish! Failing that, if one could provide a controlled discharge mechanism, that drains charge without a massive discharge channel, that would also be good. But again, we don't know how to do that. Starting from a weakly ionized probe leader, lightning has a huge positive feedback mechanism. Once it has started to go, it'll go all the way! Failing that, you fall back to a point g defense; first dissuading the creation of a conductive channel to the protected area, If an ionized leader has made it all the way down from the cloud into the region of the protected area, we don't know any way to tell it "Wrong Way. Not In My Back Yard". If the leader has come so close, you absolutely cannot stop what's probably going to happen next. All you can do is do is to design the protection system to make the best of it. or, failing at that, providing a specific, perhaps sacrificial path for the massive discharge. At last, we've come down to earth. All that lightning protection can realistically aim to do is providing a specific path. The whole aim of lightning protection is to provide a safe discharge path *past* the structure that's being protected, as opposed to a damaging path *through* the structure. A "sacrificial" path is not an option to design for. The lightning conductor *must* hang in there for the whole duration of the stroke(s), or else protection will be lost before it's all over. To keep the original discussion in perspective, all this stuff about terminals at the top end of the conductor is about trying to achieve some kind of "come here" effect in literally the final few feet of the entire lightning path (or tens of feet, if we're really lucky) to make sure the leader attaches to the terminal and not somewhere else on the structure. The well known and most reliable way to do that is to make the terminal higher than everything else, so it dominates the local electric field. But that's still no guarantee that a leader won't come wandering down at some distance off to the side, and then strike downward or even sideways from there. Bottom line: it's absolutely vital to be realistic about what lightning protection can do - and also what it cannot do. A system designed out of hopes and dreams will be the wrong system. -- 73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
Ian White, G3SEK wrote:
The well known and most reliable way to do that is to make the terminal higher than everything else, so it dominates the local electric field. But that's still no guarantee that a leader won't come wandering down at some distance off to the side, and then strike downward or even sideways from there. I have antennas, towers, tall trees, and power poles on my property. Lightning chose to strike a five foot tall Live Oak tree, killing half of it. The other half is still alive. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
"Ian White, G3SEK" wrote in message ... Ed Price wrote: I would think that lightning protection should begin with the safe equalization of charges. Oh, how we all wish! But think what that implies... If one could prevent localization of charge, there wouldn't be anything to discharge. That would require control over the weather - and again, oh how we all wish! I fully understand what I implied; this would be a technique well beyond our current capabilities. OTOH, it would be a grand concept. And we wouldn't have to "control the weather", just finesse one part of it, for a short time, in a very local region, so it might be applicable to protecting extremely valuable items and events, like maybe a shuttle launch or landing. Failing that, if one could provide a controlled discharge mechanism, that drains charge without a massive discharge channel, that would also be good. But again, we don't know how to do that. Starting from a weakly ionized probe leader, lightning has a huge positive feedback mechanism. Once it has started to go, it'll go all the way! You don't know how and I don't know how, but that's a long way from knowing that it's impossible. And I won't concede that there's no mechanism to modulate a discharge. Failing that, you fall back to a point g defense; first dissuading the creation of a conductive channel to the protected area, If an ionized leader has made it all the way down from the cloud into the region of the protected area, we don't know any way to tell it "Wrong Way. Not In My Back Yard". If the leader has come so close, you absolutely cannot stop what's probably going to happen next. All you can do is do is to design the protection system to make the best of it. or, failing at that, providing a specific, perhaps sacrificial path for the massive discharge. At last, we've come down to earth. All that lightning protection can realistically aim to do is providing a specific path. The whole aim of lightning protection is to provide a safe discharge path *past* the structure that's being protected, as opposed to a damaging path *through* the structure. A "sacrificial" path is not an option to design for. The lightning conductor *must* hang in there for the whole duration of the stroke(s), or else protection will be lost before it's all over. Sacrificial was a bad term; I didn't mean to imply that it wouldn't be durable, just that it would be the path to take the hit and protect the rest of the local area. To keep the original discussion in perspective, all this stuff about terminals at the top end of the conductor is about trying to achieve some kind of "come here" effect in literally the final few feet of the entire lightning path (or tens of feet, if we're really lucky) to make sure the leader attaches to the terminal and not somewhere else on the structure. The well known and most reliable way to do that is to make the terminal higher than everything else, so it dominates the local electric field. But that's still no guarantee that a leader won't come wandering down at some distance off to the side, and then strike downward or even sideways from there. Bottom line: it's absolutely vital to be realistic about what lightning protection can do - and also what it cannot do. A system designed out of hopes and dreams will be the wrong system. I HOPE I'm not there when it hits, and you're DREAMING if you think I'll volunteer to hold the rod. That's being REALISTIC on my part. Seriously, if all you can propose is a thick, conductive pole, then you are entering the fight at your last line of defense. Think about the whole problem, not just optimizing the existing solution. And BTW, what would be so bad about having some way to create a conductive channel from the charge to a place of YOUR choice? Even that modest goal could vastly expand the "cone of protection" that existing masts provide. Imagine being able to initiate safe cloud-to-cloud discharges. Imagine being able to direct all charge for a one-mile radius to discharge (even violently) to a designated lightning rod. One rod could protect an entire building; several rods could protect an entire large airport. My speculation about selection paths of ionization by RF excitation was just groping toward one way to create those channels, and HAARP naturally came to mind. Ed wb6wsn |
Jack Painter wrote:
"Your example of lightning was the opposite, and very rare, from the normal occurance of lightning, which is not positively charged." I won`t predict nor defend either polarity of charge in an overhead cloud. In either case it will attract the opposite charge beneath. In my example, I chose positive for the cloud because now it is popular to characterize electrons as the mobile electrical particle. My formal education was that regardless of what electrons do, current flows from plus to minus. In my hypothesis, I chose to characterize what charges were doing in the earth and other conductors. Electrons are considered mobile due to extremely small mass, so I chose them as the moving charge. Effects of lightning are identical regardless of polarity or direction of travel for practical purposes. Significant factors in lightning protection are the maximum voltage reached across a protected device and the current through it. We can`t do anything about the millions of volts and the thousands of amps behind a lightning strike. We can put high impedance between the strike and our protected people and products and we can clamp the volts across them. I`m sure that polarity makes no difference, one, the other, or both. For sure you must be prepared for both because lightning is a transient. In its start and stop, it generates powerful alternating components which include the entire radio spectrum. Arc gaps are effective protectors which have dependable breakdown voltages for a given atmosphere, temperature, pressure, presence or absence of triggering radiation, etc. Breakdown voltage is proportional to gap width for given conditions. Electrode shape is significant in the striking (breakdown) voltage. Blunt electrodes require significantly more volts to arc across than do needle points. Anyone in the TV business knows that corona discharge from the high-voltage circuit occurs from a sharp point. Once a corona is producced from a point, conductance extends as far as the corona reaches. I agree that charged air arrives in advance of a thunderstorm, whatever the polarity of charges may be. I`ve spent many years in broadcast stations and observed the storms. Before the storm arrives, tower guy insulators flash across from charges picked up by the guywire segments out of thin air. On arrival, a bolt from the sky hits a tower or towers. Maybe it`s the reverse that occurs. It makes no difference. The station and its equipment are protected by the tall towers. In lightning rods, more is better. All the stations in my experience used multitower arrays. None ever had significant lightning damage. Much of the time they were operating 24-7 and they might be dropped from the air for an instant due to a temporary overload caused by the lightning strike. The medium wave stations I worked in had blunt lightning discharge electrodes. Lowest breakdown voltage wasn`t a requirement. The final amplifiers used vacuum tubes and were sturdy. The tower base insulators all had ball gaps side by side across them. Precipitation fell right through to have little effect on their striking voltage. Tower balls never fire anyway. It`s always the Faraday screen between the primary and secondary of the tower coupling transformer thet takes the lightning hit. The impedance and striking voltage are higher at that circuit point. The screen is heavy and easily withstands lightning strikes. The shortwave stations I`ve worked in, all had arc gaps at the feedpoint of their parallel 600-ohm transmission lines. These were adjusted so that they just had 10 thousandths of an inch more than the minimum spacing required to prevent breakdown on full 100 KW carrier output with 100% modulation. These gap electrodes were consstructed like the letter V turned so one side was horizontal and the pointed ends of the V`s pointed to each other. The upward slope of the arc gap meant that heated air in the gap would rise increasing the arc distance so it might self-extinguish. We never had any lightning damage in the short wave plant with its dozens of antennas, lines and transmitters. Sharp points lower breakdown voltage. In a situation where charge across a capacitance, auch as between a cloud and the earth, has increased to the breakdown value, it happens where there there is a sharp point in the neighborhood of the charge concentration. Blunt electrodes require higher potential to flash over than sharp electrodes. For given electrodes in a controlled environment, the distance between electrodes can be calibrated in volts required to jump the gap. Arc gaps are spaced to clamp the maximum voltage across them to a safe value. CRC`s "Handbook of Chemistry and Physics has a table of the voltages for blunt and sharp electrodes. Best regards, Richard Harrison, KB5WZI |
"Ed Price" writes:
... And BTW, what would be so bad about having some way to create a conductive channel from the charge to a place of YOUR choice? Even that modest goal could vastly expand the "cone of protection" that existing masts provide. Imagine being able to initiate safe cloud-to-cloud discharges. Imagine being able to direct all charge for a one-mile radius to discharge (even violently) to a designated lightning rod. One rod could protect an entire building; several rods could protect an entire large airport. My speculation about selection paths of ionization by RF excitation was just groping toward one way to create those channels, and HAARP naturally came to mind. A long time ago, there was some (theoretical at least) effort to see whether UV lasers could be used to create an ionized channel over a long distance. Something like that might do the job. OTOH a rainstorm is generally pretty opaque to UV. Teh RF excitation has already been tried -- I think someone has a patent on it. One problem with it is that where there is lightning there tends to be wind, so that the ionized air is blown away faster than it can be generated. Regards, Allen WA0OHE |
On 07 Jan 2005 16:46:54 -0600, Allen Windhorn
wrote: My speculation about selection paths of ionization by RF excitation was just groping toward one way to create those channels, and HAARP naturally came to mind. A long time ago, there was some (theoretical at least) effort to see whether UV lasers could be used to create an ionized channel over a long distance. Hi Guys, One has to wonder about the consequence of double jeopardy standing beneath that antenna (HAARP experiment) or holding the laser. Think insurance covers this? Supply shop foreman (perplexed): "Another laser? What happened to the last one?" Tech (smoke curling up from clothes): "ummmm, burned out real quick-like. Could you hurry? They say more rain is on the way!" 73's Richard Clark, KB7QHC |
"Richard Clark" wrote On Fri, 7 Jan 2005 01:53:00 -0500, "Jack Painter" wrote: Interested in your comments *after* you have read the study. http://lightning-protection-institut...-terminals.pdf Hi Jack, "It is quite obvious from these plots that the experimentally determined electric field strength is less than the "simple-minded" V/d value." Interesting brush-off so early in the paper begs for real editorial control. As very few would experience lighting sourced from a grid of wire 5M overhead this paper seems an example of the "laboratory factor" it set out to examine and yields a paper confined to laboratory arcana. All fine and well, but what is the point? "There is an urgent need for detailed theoretical modelling which can quantify the space charge effects around air terminals, particularly in relation to upleader development." Which seems at odds with your statement: On Fri, 7 Jan 2005 01:17:07 -0500, "Jack Painter" wrote: The junk-science of early-streamer-emission but I'm not terribly interested. I wasn't particularly intrigued by Pons and Fleishman either, beyond the hubris of their closet drama. It would seem some have a desperate need to topple Franklin from a pedestal of their own building. (Theirs is called the fallacy of "present mindedness.") I'm satisfied that contemporary Europeans held him in high esteem for many noble achievements. Reductionists are measured against their own few of baser metal. Hope you found that interesting, but I doubt it - rather banal stuff. 73's Richard Clark, KB7QHC Richard, Thanks. I always find your comments about scientific material interesting. There is some monumental evidence accumulating to contest ESE/CTS, and this begs the question that if there is such a political fight over preventing its presentation to the whole IEEE body for a vote, what are they so afraid of? Russian scientists have now been commissioned to find (contrary to all other studies) that the principle works. Avoiding the comments about streamers in the referenced paper though, my point really was that they arrived at a statistical average they may have been looking for, but attempts to remove the laboratory principle appeared honest to me (and to others). Your opinion there is important, at least to me. 73, Jack Painter Virginia Beach, VA |
On Fri, 7 Jan 2005 20:23:28 -0500, "Jack Painter"
wrote: Thanks. I always find your comments about scientific material interesting. Hi Jack, Well, when I look at these tempests in a teapot, I reduce things myself. For instance, this distinction between a sharp point on a rod and a blunt point on a rod. Nature hardly takes the time in a lightning strike to be so particular. This is so multivariate a problem that no single variable is going to be a determiner at this rather fussy level of detail. The reduction consists of the logic in the extreme. We have a blunt rod, we have a sharp rod. It is purported (or I have read the controversy completely wrong) that this makes a difference, somehow. We put those on a yet blunter rod (a tower); or with a yet blunter rod (another tower) nearby (in the scale of miles transit, nearby by hundreds of yards/meters/feet/inches/cm is very proximal) and yet such neighbors are not the choice of the stroke (or they are and this upsets the catalogue of evidence). Hence the reductio ad absurdum is that blunt points are significant, but not too significant. All that aside - I do not dismiss the topic entirely. It offers something I have found in my own work. The near field area to a monopole: http://home.comcast.net/~kb7qhc/ante...ical/index.htm displays a very marked disturbance above it. The introduction of a metal pole into space distorts it far beyond the borders of the graphic pointed to. In a sense, it acts like (in my imagination) the vertex of a energy well; or at greater scales, a dimple in the fabric of the æther. Such analogies and illustrations are intriguing, but not conclusive of anything but how to intellectually amuse while monkeying with numbers. 73's Richard Clark, KB7QHC |
"Richard Clark" wrote in message ... On 07 Jan 2005 16:46:54 -0600, Allen Windhorn wrote: My speculation about selection paths of ionization by RF excitation was just groping toward one way to create those channels, and HAARP naturally came to mind. A long time ago, there was some (theoretical at least) effort to see whether UV lasers could be used to create an ionized channel over a long distance. Hi Guys, One has to wonder about the consequence of double jeopardy standing beneath that antenna (HAARP experiment) or holding the laser. Think insurance covers this? Supply shop foreman (perplexed): "Another laser? What happened to the last one?" Tech (smoke curling up from clothes): "ummmm, burned out real quick-like. Could you hurry? They say more rain is on the way!" 73's Richard Clark, KB7QHC Well, I could easily imagine a laser protected within a large conductive lightning rod. All you need is a 1/" hole in an otherwise well-shielded structure. Maybe a bit larger to allow for pointing, or you could put some optics safely outside the rod. Regarding the RF excitation, I assumed that a single-point source would be dumb, because the best ionization path would be right back to YOU. But an array of exciters, electronically steered to create a sufficient power density at a focal point, is a lot smarter. Again, I don't know if the technique would work, but an electronically steered (more like focusing) array would be one way to do it. One poster said that the ionized channel might blow away in the wind. Maybe a quick system could "paint" an ionization channel fast enough. Maybe a system could detect and take advantage of leaders, to create a shorter path. Ed wb6wsn |
"Jack Painter" wrote in message news:lCGDd.9973$B95.1664@lakeread02... "Richard Clark" wrote On Fri, 7 Jan 2005 01:53:00 -0500, "Jack Painter" wrote: Interested in your comments *after* you have read the study. http://lightning-protection-institut...-terminals.pdf Hi Jack, "It is quite obvious from these plots that the experimentally determined electric field strength is less than the "simple-minded" V/d value." Interesting brush-off so early in the paper begs for real editorial control. As very few would experience lighting sourced from a grid of wire 5M overhead this paper seems an example of the "laboratory factor" it set out to examine and yields a paper confined to laboratory arcana. All fine and well, but what is the point? "There is an urgent need for detailed theoretical modelling which can quantify the space charge effects around air terminals, particularly in relation to upleader development." Which seems at odds with your statement: On Fri, 7 Jan 2005 01:17:07 -0500, "Jack Painter" wrote: The junk-science of early-streamer-emission but I'm not terribly interested. I wasn't particularly intrigued by Pons and Fleishman either, beyond the hubris of their closet drama. It would seem some have a desperate need to topple Franklin from a pedestal of their own building. (Theirs is called the fallacy of "present mindedness.") I'm satisfied that contemporary Europeans held him in high esteem for many noble achievements. Reductionists are measured against their own few of baser metal. Hope you found that interesting, but I doubt it - rather banal stuff. 73's Richard Clark, KB7QHC Richard, Thanks. I always find your comments about scientific material interesting. There is some monumental evidence accumulating to contest ESE/CTS, and this begs the question that if there is such a political fight over preventing its presentation to the whole IEEE body for a vote, what are they so afraid of? Russian scientists have now been commissioned to find (contrary to all other studies) that the principle works. Those "Russian scientists" often seemed to come up with controversial and unrepeatable results. Old cold warriors wondered if the Russians were that much smarter or dumber. Then, in the 90's, we found that a lot of that weird stuff was internal political smoke and mirrors, more related to funding than science. Ed wb6wsn |
"Ed Price" wrote "Richard Clark" wrote in message ... On 07 Jan 2005 16:46:54 -0600, Allen Windhorn wrote: My speculation about selection paths of ionization by RF excitation was just groping toward one way to create those channels, and HAARP naturally came to mind. A long time ago, there was some (theoretical at least) effort to see whether UV lasers could be used to create an ionized channel over a long distance. Hi Guys, One has to wonder about the consequence of double jeopardy standing beneath that antenna (HAARP experiment) or holding the laser. Think insurance covers this? Supply shop foreman (perplexed): "Another laser? What happened to the last one?" Tech (smoke curling up from clothes): "ummmm, burned out real quick-like. Could you hurry? They say more rain is on the way!" 73's Richard Clark, KB7QHC Well, I could easily imagine a laser protected within a large conductive lightning rod. All you need is a 1/" hole in an otherwise well-shielded structure. Maybe a bit larger to allow for pointing, or you could put some optics safely outside the rod. Regarding the RF excitation, I assumed that a single-point source would be dumb, because the best ionization path would be right back to YOU. But an array of exciters, electronically steered to create a sufficient power density at a focal point, is a lot smarter. Again, I don't know if the technique would work, but an electronically steered (more like focusing) array would be one way to do it. One poster said that the ionized channel might blow away in the wind. Maybe a quick system could "paint" an ionization channel fast enough. Maybe a system could detect and take advantage of leaders, to create a shorter path. Ed wb6wsn Hi Ed, using high powered lasers to "paint" a thunderstorm cloud has been done, and whether reliably or not, was able to trigger lightning. It hasn't translated into practical protection schemes yet, but that could simply be economics. As a means of triggering lightning to a safe point away from vulnerable assets, it still leaves the possibility that some storms are so powerful that nothing short of an extensive, multi-point array of lasers could ever offer protection at an individual point. It is generally so much less expensive to employ catenary wires overhead, build faraday-cages around, and position air terminals in appropriate areas than the costs of such a laser system. There would also be a new class of airspace required for operation of such lasers. Something like a "no-fly zone" in fact! ;-) 73, Jack Painter Virginia Beach, Virginia |
On Sat, 8 Jan 2005 05:42:30 -0800, "Ed Price" wrote:
or you could put some optics safely outside Supply shop foreman (shocked): "You want WHAT?" Tech (still smoldering): "You know, one of those Disco Balls. We're gonna spread the beam, hit it, and hope it -ummmmm- clears the air. You got many in stock? We may need a few. "Oh yeah, another laser too." 73's Richard Clark, KB7QHC |
On Sat, 8 Jan 2005 05:52:39 -0800, "Ed Price" wrote:
Those "Russian scientists" often seemed to come up with controversial and unrepeatable results. Hi Ed, There certainly seems to be a mixed bag of what's useful out of the old USSR. However, their math software applications have been killers in the capitalistic marketplace. One other jewel came from their rocket division that built the most powerful engines known, and then the bureaucracy ordered them scrapped because they abandoned their man on the moon program. The engineer in charge deliberately ignored this order and had something like a couple of hundred wrapped up and put into storage. They are making quite a killing on selling those right now. Another story is their development of a supersonic torpedo. That's right, a jet powered torpedo that can dart through the ocean at 600MPH. It was speculated that it was the cause of the sinking of their submarine, the Kursk. It was thought that the propellant lit off in its bay, and the rest is history. 73's Richard Clark, KB7QHC |
"Jack Painter" wrote in message news:emUDd.11563$B95.6120@lakeread02... "Ed Price" wrote SNIP Regarding the RF excitation, I assumed that a single-point source would be dumb, because the best ionization path would be right back to YOU. But an array of exciters, electronically steered to create a sufficient power density at a focal point, is a lot smarter. Again, I don't know if the technique would work, but an electronically steered (more like focusing) array would be one way to do it. One poster said that the ionized channel might blow away in the wind. Maybe a quick system could "paint" an ionization channel fast enough. Maybe a system could detect and take advantage of leaders, to create a shorter path. Ed wb6wsn Hi Ed, using high powered lasers to "paint" a thunderstorm cloud has been done, and whether reliably or not, was able to trigger lightning. It hasn't translated into practical protection schemes yet, but that could simply be economics. As a means of triggering lightning to a safe point away from vulnerable assets, it still leaves the possibility that some storms are so powerful that nothing short of an extensive, multi-point array of lasers could ever offer protection at an individual point. It is generally so much less expensive to employ catenary wires overhead, build faraday-cages around, and position air terminals in appropriate areas than the costs of such a laser system. There would also be a new class of airspace required for operation of such lasers. Something like a "no-fly zone" in fact! ;-) 73, Jack Painter Virginia Beach, Virginia More like a "dead-fly" zone. Yeah, aircraft (and satellite / astronaut) protection are not trivial concerns when you start squirting power into the air. BTW, I seem to recall the use of small (sounding?) rockets used around the perimeter of the Kennedy launch complex. I don't recall if these rockets trailed a thin wire, or if their exhaust plume was sufficient to trigger a lightning discharge. Anyway, I thought I recall these small expendable rockets being used as a lightning diversion technique to protect the exposed launch vehicle. (Yes, I know they also use catenary wires from the tower to the ground, but the rocket technique was supposedly to condition the area around the vehicle just as launch occurred, and the tower was moved away from the vehicle.) Ed wb6wsn |
"Ed Price" wrote BTW, I seem to recall the use of small (sounding?) rockets used around the perimeter of the Kennedy launch complex. I don't recall if these rockets trailed a thin wire, or if their exhaust plume was sufficient to trigger a lightning discharge. Anyway, I thought I recall these small expendable rockets being used as a lightning diversion technique to protect the exposed launch vehicle. (Yes, I know they also use catenary wires from the tower to the ground, but the rocket technique was supposedly to condition the area around the vehicle just as launch occurred, and the tower was moved away from the vehicle.) Ed wb6wsn Yessir Ed. At NASA Wallops Island (Eastern Shore, VA) they regularly launch sounding rockets. We have had one land well off course about 300 yards off the Virginia Beach Oceanfront late one night. I was able to help call off the extensive search involving air, sea and land assets when I convinced District to check with Group Eastern Shore (who I had heard make the Securite' announcement earlier, warning of the rocket launches). Witnesses at the beach had reported a flaming plane crash in the water. When the CG Helo pilot realized that it was probably a rocket, (and there were still more scheduled) he bugged out fast. As to triggering lightning with rockets, yes they do trail wire, and this method of lightning experimentation provides excellent results. Makes sense they would clear the air first before a launch, but I think they are pretty sure lightning isn't likely before they light one of those candles, huh? The static charges from a rocket alone must be impressive. Maybe it could attract lightning from a lot farther than normally considered in the risk-zone. Jack Va Beach |
"Ed Price" wrote in message news:nt1Ed.17168$yW5.12224@fed1read02... "Barry Horowitz" wrote in message ps.com... DON'T FORGET!!! When the paired mates, ARGON and NEON, are "coupled," they produce LIGHTNING aka [BLITZ!!!] ... they both form absolutely NO OXIDES http://carpathian_bronze.tripod.com/antarii_deck2.html A good example of sufficiently advanced blather being indistinguishable from knowledge. Ed wb6wsn Well, Ed, It is difficult to produce oxides without oxygen, but bull**** is easy to come up with. 73 H. |
More sense could be derived by considering lightning and radio-ground
conductors to be transmission lines. It's also more simple than reams of words. But perhaps its asking too much of the present-day school and engineering educational system which neglects arithmetic. Ignorant school teachers frighten pupils by calling it Mathematics. As I've said before, the culled kids who live in the sewers of Rio de Janerio, South America, are better (self) educated. |
Reg Edwards wrote: More sense could be derived by considering lightning and radio-ground conductors to be transmission lines. It's also more simple than reams of words. But perhaps its asking too much of the present-day school and engineering educational system which neglects arithmetic. Ignorant school teachers frighten pupils by calling it Mathematics. As I've said before, the culled kids who live in the sewers of Rio de Janerio, South America, are better (self) educated. Ridiculous. |
Kids considered by the City Authorities to be a nuisance, living with rats in the sewers of Rio are ocasionally culled, perhaps not explicitly by the Authorities, to reduce their nunbers by police armed with guns. Amongst other ways of making a living they survive be selling home-brewed cigarettes, loaded with cannobis and more powerful drugs on the city streets. It is not surprising why the Authorities consider them to be a nuisance - it has a bad effect on the wealthy tourist trade. Now selling cigarettes involves monetary and arithmetical transactions. Accepting bank notes and coins and giving correct change. Mental calculations involve percent of drugs per inch of cigarette length, the number of cigarettes in the pack, wastage etc. All must be done very fast before an armed policeman appears. And must be done accurately and honestly to avoid upsetting customers with the consequent longer-term bad effect of loss in trade. There has evolved in the sewers of Rio an arithmetical method of addition, subtraction, multiplication and division, altogether different from the Arabic procedures (Baghdad, Basrah, Mosul, before foreign weapons of mass destruction were introduced) now adopted by the rest of the educated world. Not so very long ago a small party of professors, Phd's, students etc., from an English univerity made an expedition to Rio specifically to investigate this apparent revolution in the very foundation of Mathematics. They returned with a new insight into how the human brain works with numbers and retired to study and then present their findings. Since then all has been silence. I have not spent much time with Google. But there is no doubt that the self-taught sewer kids of Rio are better educated at arithmetic than the so-called engineers who argue amongst themselves in words on this newsgroup without any use of numbers and relative quantities. --- Reg. |
Reg Edwards wrote: Kids considered by the City Authorities to be a nuisance, living with rats in the sewers of Rio are ocasionally culled, perhaps not explicitly by the Authorities, to reduce their nunbers by police armed with guns. Amongst other ways of making a living they survive be selling home-brewed cigarettes, loaded with cannobis and more powerful drugs on the city streets. It is not surprising why the Authorities consider them to be a nuisance - it has a bad effect on the wealthy tourist trade. Now selling cigarettes involves monetary and arithmetical transactions. Accepting bank notes and coins and giving correct change. Mental calculations involve percent of drugs per inch of cigarette length, the number of cigarettes in the pack, wastage etc. All must be done very fast before an armed policeman appears. And must be done accurately and honestly to avoid upsetting customers with the consequent longer-term bad effect of loss in trade. There has evolved in the sewers of Rio an arithmetical method of addition, subtraction, multiplication and division, altogether different from the Arabic procedures (Baghdad, Basrah, Mosul, before foreign weapons of mass destruction were introduced) now adopted by the rest of the educated world. Not so very long ago a small party of professors, Phd's, students etc., from an English univerity made an expedition to Rio specifically to investigate this apparent revolution in the very foundation of Mathematics. They returned with a new insight into how the human brain works with numbers and retired to study and then present their findings. Or else lose their grant funding. Since then all has been silence. I have not spent much time with Google. But there is no doubt that the self-taught sewer kids of Rio are better educated at arithmetic than the so-called engineers who argue amongst themselves in words on this newsgroup without any use of numbers and relative quantities. Better educated? Ridiculous. More proficient, perhaps. |
On Tue, 11 Jan 2005 21:18:39 +0000 (UTC), "Reg Edwards"
wrote: loaded with cannobis and more powerful drugs Hi Reggie, If you are expected to be taken seriously, even the sewer rats of Rio know how to spell hemp. 73's Richard Clark, KB7QHC |
"Richard Clark" wrote loaded with cannobis and more powerful drugs Hi Reggie, If you are expected to be taken seriously, even the sewer rats of Rio know how to spell hemp. ========================== Hi Dick, Yes, at the time, I was aware of the mis-spelling. But I could't think of the name 'hemp' which even I CAN spell correctly. Very interesting, its the only defect you could find in my story. Your "If you are expected to be taken seriously" is an indication that you think there is something serious in what I say. Regardless of South American un-culled sewer rats - Engineers who regularly demonstrate they are afraid of using numbers can hardly be considered to be well educated. (Refer to Kelvin). This criticism is not so much directed against individuals as it is against the present-day, Western World engineering educational system in which university professors just sit on their fat, lazy, well-paid, self-satisfied arses, obtaining easy money under mutually-plagiarising false pretences. ---- Reginald, G4FGQ |
On Wed, 12 Jan 2005 13:34:31 +0000 (UTC), "Reg Edwards"
wrote: | |"Richard Clark" wrote | loaded with cannobis and more powerful drugs | | Hi Reggie, | | If you are expected to be taken seriously, even the sewer rats of Rio | know how to spell hemp. | |========================== |Hi Dick, | |Yes, at the time, I was aware of the mis-spelling. But I could't think of |the name 'hemp' which even I CAN spell correctly. Very interesting, its the |only defect you could find in my story. If you would have just typed "cannobis" in Google, it would have asked: "Do you mean: cannabis?" | |Your "If you are expected to be taken seriously" is an indication that you |think there is something serious in what I say. Never. | |Regardless of South American un-culled sewer rats - Engineers who regularly |demonstrate they are afraid of using numbers can hardly be considered to be |well educated. (Refer to Kelvin). Hmmm. The USA is now being overrun with denizens of the countries to the south, including no doubt some South American sewer rats. By your estimation, the education level here should have improved. I think not. For example, I left a pair of slacks at the dry cleaners a few days ago. The fee was $1.75 (USD). I gave the girl $10.00 and she broke out a calculator to determine that my change was $8.25. Contrast this to a tale related to me by an old friend. Jim was in the U.S. Marine Corps when the flight of the Enola Gay took place. Shortly after, he and his group were sent up some river in China to ferret out some Japs...sorry...Asians who hadn't gotten the word yet that they had lost. The Marines set up a camp and immediately began a trade relationship with the local Chinese "service industry." Jim said it took all of 15-20 minutes for the natives to master the U.S. currency system. (It probably would have taken them a couple of hours to figure out the British system of the day [G]) |
Richard Clark wrote:
On Sat, 8 Jan 2005 05:52:39 -0800, "Ed Price" wrote: Those "Russian scientists" often seemed to come up with controversial and unrepeatable results. Hi Ed, snip Another story is their development of a supersonic torpedo. That's right, a jet powered torpedo that can dart through the ocean at 600MPH. It was speculated that it was the cause of the sinking of their submarine, the Kursk. It was thought that the propellant lit off in its bay, and the rest is history. Rocket powered, actually. Interesting how it works physically. I have read some speculation on making manned submarines on the same principle. I would think running into a whale would be a serious issue, though, even if unlikely. tom K0TAR |
Wes Stewart wrote:
If you would have just typed "cannobis" in Google, it would have asked: "Do you mean: cannabis?" Oops Wes, you have just joined the FBI's most wanted list. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
"Reg Edwards" wrote in message ... Kids considered by the City Authorities to be a nuisance, living with rats in the sewers of Rio are ocasionally culled, perhaps not explicitly by the Authorities, to reduce their nunbers by police armed with guns. Now selling cigarettes involves monetary and arithmetical transactions. Accepting bank notes and coins and giving correct change. Mental calculations involve percent of drugs per inch of cigarette length, the number of cigarettes in the pack, wastage etc. All must be done very fast before an armed policeman appears. And must be done accurately and honestly to avoid upsetting customers with the consequent longer-term bad effect of loss in trade. Or much more likely, a "culling" by customers / compettiors. So why would you expect this particular geographic environment to provide unique educational stimulus, above and beyond the crystal meth dealers of LA or the rock cocaine vendors of Chicago? There has evolved in the sewers of Rio an arithmetical method of addition, subtraction, multiplication and division, altogether different from the Arabic procedures now adopted by the rest of the educated world. Not so very long ago a small party of professors, Phd's, students etc., from an English univerity made an expedition to Rio specifically to investigate this apparent revolution in the very foundation of Mathematics. They returned with a new insight into how the human brain works with numbers and retired to study and then present their findings. Since then all has been silence. After they sobered up, they realized that the Brazilian Renaissance only changed the course of world thinking for 12 minutes. Ed wb6wsn |
"Reg Edwards" wrote in message ... "Richard Clark" wrote loaded with cannobis and more powerful drugs Hi Reggie, If you are expected to be taken seriously, even the sewer rats of Rio know how to spell hemp. ========================== Hi Dick, Yes, at the time, I was aware of the mis-spelling. But I could't think of the name 'hemp' which even I CAN spell correctly. Very interesting, its the only defect you could find in my story. Your "If you are expected to be taken seriously" is an indication that you think there is something serious in what I say. Regardless of South American un-culled sewer rats - Engineers who regularly demonstrate they are afraid of using numbers can hardly be considered to be well educated. (Refer to Kelvin). This criticism is not so much directed against individuals as it is against the present-day, Western World engineering educational system in which university professors just sit on their fat, lazy, well-paid, self-satisfied arses, obtaining easy money under mutually-plagiarising false pretences. ---- Reginald, G4FGQ But you just cited an example of profs and students organizing a research expedition to Rio to count the sewer rats, or was it to study how the sewer rats count? Ed wb6wsn |
"Wes Stewart" wrote in message ... On Wed, 12 Jan 2005 13:34:31 +0000 (UTC), "Reg Edwards" wrote: | |"Richard Clark" wrote | loaded with cannobis and more powerful drugs | | Hi Reggie, | | If you are expected to be taken seriously, even the sewer rats of Rio | know how to spell hemp. | |========================== |Hi Dick, | |Yes, at the time, I was aware of the mis-spelling. But I could't think of |the name 'hemp' which even I CAN spell correctly. Very interesting, its the |only defect you could find in my story. If you would have just typed "cannobis" in Google, it would have asked: "Do you mean: cannabis?" | |Your "If you are expected to be taken seriously" is an indication that you |think there is something serious in what I say. Never. | |Regardless of South American un-culled sewer rats - Engineers who regularly |demonstrate they are afraid of using numbers can hardly be considered to be |well educated. (Refer to Kelvin). Hmmm. The USA is now being overrun with denizens of the countries to the south, including no doubt some South American sewer rats. By your estimation, the education level here should have improved. I think not. For example, I left a pair of slacks at the dry cleaners a few days ago. The fee was $1.75 (USD). I gave the girl $10.00 and she broke out a calculator to determine that my change was $8.25. Contrast this to a tale related to me by an old friend. Jim was in the U.S. Marine Corps when the flight of the Enola Gay took place. Shortly after, he and his group were sent up some river in China to ferret out some Japs...sorry...Asians who hadn't gotten the word yet that they had lost. The Marines set up a camp and immediately began a trade relationship with the local Chinese "service industry." Jim said it took all of 15-20 minutes for the natives to master the U.S. currency system. (It probably would have taken them a couple of hours to figure out the British system of the day [G]) Thirty minutes after you acclimated them to US funding, the limeys would have been priced out of the market! No wonder Reg is perennially ****ed at the world; lackanookie! Ed wb6wsn |
"Tom Ring" wrote in message . .. Richard Clark wrote: On Sat, 8 Jan 2005 05:52:39 -0800, "Ed Price" wrote: Those "Russian scientists" often seemed to come up with controversial and unrepeatable results. Hi Ed, snip Another story is their development of a supersonic torpedo. That's right, a jet powered torpedo that can dart through the ocean at 600MPH. It was speculated that it was the cause of the sinking of their submarine, the Kursk. It was thought that the propellant lit off in its bay, and the rest is history. Rocket powered, actually. Interesting how it works physically. I have read some speculation on making manned submarines on the same principle. I would think running into a whale would be a serious issue, though, even if unlikely. tom K0TAR Now that would be darn considerate of them, as we could track them all without leaving Narragansett Bay. Ed wb6wsn |
Not so very long ago a small party of professors, Phd's, students etc., from an English univerity made an expedition to Rio specifically to investigate this apparent revolution in the very foundation of Mathematics. They returned with a new insight into how the human brain works with numbers and retired to study and then present their findings. Since then all has been silence. After they sobered up, they realized that the Brazilian Renaissance only changed the course of world thinking for 12 minutes. Ed wb6wsn =================================== More likely, out of necessity, the investigators had to buy so many cannabis-loaded cigarettes from sewer kids they returned from the expedition as confirmed addicts. ---- Reg |
Reg Edwards wrote:
More likely, out of necessity, the investigators had to buy so many cannabis-loaded cigarettes from sewer kids they returned from the expedition as confirmed addicts. Last I heard, there's no proof that cannabis is physically addicting. -- 73, Cecil http://www.qsl.net/w5dxp ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
If you stretch a string on a globe from London to Florida, it will show the 'great circle' route that's the shortest, and that should be your plane's path, barring storme, hurricanes, etc. You'll see that it comes really close to the eastern Canadian provinces. In fact the Avalon Peninsuala in the most eastern part of the island portion of the province of Newfoundland and Labrador, Canada, is a 'Way Point' for many transatlantic flights headed to/from Europe. Clear days Transatlantic flight con-trails, at 30,000 feet etc. can be seen almost continuously. That is why so many of the flights that were prevented from entering US air space 9/11 had to land in eastern Canada. Many US/Canada friendships were founded between grounded travellers that day and eastern and western Canadians who voluntarily accommodated them during the delay. Cape Spear near St John's is the most easterly point in North America. Marconi received the first transatlantic wireless telegraph signal near St John's in Dec. 1901. French is one of the 'Official Languages' in Canada. A significant percentage of the population, mainly in Quebec, New Brunswick, but also elsewhere in Canada, is French speaking. Many/most are bilingual. Same way Spanish is significant in the USA? The word 'Cajun' in southern US comes from the French word "Acadian"; originally inhabitants of Acadia or what is now the eastern Canadian Province of Nova Scotia. Terry. PS. Staff at the National Historic Park at Signal Hill, St. John's, which incorporates the memorial and events which celebrate Marconi's first wireless telegraph reception say that visitors unaware of the approximately 1800 miles across the Atlantic, (4.3 hours by jet to London-Heathrow) will sometimes ask "Can you see across to England/Ireland etc.". The answer is; "No, but sometimes you can see "Whales"! :-) And sometimes icebergs as well. |
AM radio reception inside passenger planes?
On Mon, 13 Dec 2004 08:47:43 -0600, Richard Harrison wrote:
Some Guy wrote: "I have no trouble receiving FM radio broadcasts on a small am/fm radio I sometimes listen to while onboard commercial jet sirliners (flying at cruise altitude), but I bever seem to be able to pick up AM radio stations. It`s just static across the AM band. Any explanation for this?" Fuselage of the airliner acts as a waveguide below cutoff frequency (where diameter is at least 1/2-wavelength). Below cutoff, attenuation soars rapidly. FM wavelength is about 3 meters. AM wavelength is about 300 meters. Propagation of FM inside the fuselage is OK. Propagation of AM inside the fuselage vanishes quickly. You need to stick the suction cups of your Zenith portable`s Wave Magnet to a window to get AM reception. Best regards, Richard Harrison, KB5WZI Years ago I could get some shortwave reception by placing the radio's whip antenna across the window and lowering the shade to keep in place (and hide the radio). MW stations were generally too weak to listen to. FM was a jumble at altitude. These days RFI from the cabin entertainment systems completely blanks out everything so don't bother trying. Be thankful MP3 players still work. -- Chuck Forsberg www.omen.com 503-614-0430 Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc "The High Reliability Software" 10255 NW Old Cornelius Pass Portland OR 97231 FAX 629-0665 |
AM radio reception inside passenger planes?
In message , Chuck
Forsberg WA7KGX N2469R writes On Mon, 13 Dec 2004 08:47:43 -0600, Richard Harrison wrote: Some Guy wrote: "I have no trouble receiving FM radio broadcasts on a small am/fm radio I sometimes listen to while onboard commercial jet sirliners (flying at cruise altitude), but I bever seem to be able to pick up AM radio stations. It`s just static across the AM band. Any explanation for this?" Fuselage of the airliner acts as a waveguide below cutoff frequency (where diameter is at least 1/2-wavelength). Below cutoff, attenuation soars rapidly. FM wavelength is about 3 meters. AM wavelength is about 300 meters. Propagation of FM inside the fuselage is OK. Propagation of AM inside the fuselage vanishes quickly. You need to stick the suction cups of your Zenith portable`s Wave Magnet to a window to get AM reception. Best regards, Richard Harrison, KB5WZI Years ago I could get some shortwave reception by placing the radio's whip antenna across the window and lowering the shade to keep in place (and hide the radio). MW stations were generally too weak to listen to. FM was a jumble at altitude. These days RFI from the cabin entertainment systems completely blanks out everything so don't bother trying. Be thankful MP3 players still work. With a window seat, FM works OK, especially (as has been said) with the whip held close to the window. You can also get some SW reception. [I remember listening to the BBC World service at 35,000 feet.] MW AM is pretty useless (at those frequencies, the airframe is a Faraday cage). Some airlines are/were OK about using radio receivers during the flight, but I understand that these days, regardless of what the airline says, you might get challenged by some 'over enthusiastic' security guy during the normal departure security checks. About 10 years ago (before the recent troubles), I did do some listening on a UK-USA transatlantic flight. On approaching North America, I was initially surprised that the first FM station I heard was French-speaking (from Quebec, of course). I was relieved when I realised that the 'driver' had not got lost. -- Ian |
AM radio reception inside passenger planes?
Chuck Forsberg WA7KGX N2469R wrote:
On Mon, 13 Dec 2004 08:47:43 -0600, Richard Harrison wrote: Some Guy wrote: "I have no trouble receiving FM radio broadcasts on a small am/fm radio I sometimes listen to while onboard commercial jet sirliners (flying at cruise altitude), but I bever seem to be able to pick up AM radio stations. It`s just static across the AM band. Any explanation for this?" Fuselage of the airliner acts as a waveguide below cutoff frequency (where diameter is at least 1/2-wavelength). Below cutoff, attenuation soars rapidly. FM wavelength is about 3 meters. AM wavelength is about 300 meters. Propagation of FM inside the fuselage is OK. Propagation of AM inside the fuselage vanishes quickly. You need to stick the suction cups of your Zenith portable`s Wave Magnet to a window to get AM reception. Best regards, Richard Harrison, KB5WZI Years ago I could get some shortwave reception by placing the radio's whip antenna across the window and lowering the shade to keep in place (and hide the radio). MW stations were generally too weak to listen to. FM was a jumble at altitude. These days RFI from the cabin entertainment systems completely blanks out everything so don't bother trying. Be thankful MP3 players still work. One notes that you need to have permission from the plane's pilot to operate any sort of radio (including a receiver) while in flight. With receivers, the concern is with things like Local Oscillator or other leakage signals. Whether this is a legitimate concern is a topic of discussion (e.g. they've flown commercial planes with an antenna and logging spectrum analyzer in an overhead bin, and discovered that lots of folks forget to turn off their cell phones), but the fact remains that the regulations say no radios, except those permitted by the pilot in command. |
AM radio reception inside passenger planes?
Jim Lux wrote:
Chuck Forsberg WA7KGX N2469R wrote: On Mon, 13 Dec 2004 08:47:43 -0600, Richard Harrison wrote: Some Guy wrote: "I have no trouble receiving FM radio broadcasts on a small am/fm radio I sometimes listen to while onboard commercial jet sirliners (flying at cruise altitude), but I bever seem to be able to pick up AM radio stations. It`s just static across the AM band. Any explanation for this?" Fuselage of the airliner acts as a waveguide below cutoff frequency (where diameter is at least 1/2-wavelength). Below cutoff, attenuation soars rapidly. FM wavelength is about 3 meters. AM wavelength is about 300 meters. Propagation of FM inside the fuselage is OK. Propagation of AM inside the fuselage vanishes quickly. You need to stick the suction cups of your Zenith portable`s Wave Magnet to a window to get AM reception. Best regards, Richard Harrison, KB5WZI Years ago I could get some shortwave reception by placing the radio's whip antenna across the window and lowering the shade to keep in place (and hide the radio). MW stations were generally too weak to listen to. FM was a jumble at altitude. These days RFI from the cabin entertainment systems completely blanks out everything so don't bother trying. Be thankful MP3 players still work. One notes that you need to have permission from the plane's pilot to operate any sort of radio (including a receiver) while in flight. With receivers, the concern is with things like Local Oscillator or other leakage signals. Whether this is a legitimate concern is a topic of discussion (e.g. they've flown commercial planes with an antenna and logging spectrum analyzer in an overhead bin, and discovered that lots of folks forget to turn off their cell phones), but the fact remains that the regulations say no radios, except those permitted by the pilot in command. And the reality is the pilot in command of commercial aircraft has to follow the policies of his employer, most of which take the safe route of banning everything that might even remotely cause a problem. -- Jim Pennino Remove .spam.sux to reply. |
AM radio reception inside passenger planes?
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