don (05/09/83)
Subject: Tesla and AC Yes, Tesla invented the polyphase motor which he sold to Westinghouse. That was a good ten years or so before he began playing with High frequency current, so the Tesla coil really had nothing to do with that. Tesla is also acknowleged as one of the first people to use tuned coupled circuits in wireless telegraphy. In a long series of court battles that eventually overturned Marconi's patents, Tesla and an American inventer named Stone were both credited with inventing the items that Marconi (who was a really somewhat of a crook by the way) had claimed. (Imagine the mess if Henery Ford had patented the automobile. The situation was similar.) Radio was one of those ideas whose time had come. So many people invented wireless telegraphy at the same time its hard to tell who deserves credit. I think most people now agree that Lodge in England and Popov (sp?) in Russia were the earliest workers.
markb (05/12/83)
There is some evidence to show that Edison invented a wireless telegraphy system even before Hertz discovered EM waves. The only application Edison ever used it for was a method for a train the pick up telegraph messages off the wire parallel to the track while moving. Sorry there is no reference for this it was in a popular electronics around 1972-3. Mark Biggar ...decvax!trw-unix!sdcrdcf!markb
eugenez@azure.UUCP (Eugene Zinter) (03/01/85)
When Tesla came the the United States (from Yugoslavia), he had heard of Edison. I believe he actually looked up to him as a great person. AS someone to be like. This all changed after being employed under Edison. Tesla had at one time wondered if the time he spent in college was wasted. This was because he noted that Edison had no college education. But when he discovered how Edison did things, he decided his college years were well spent. Tesla reasoned this way with how Edison solved problems. If Edison were looking for a needle in a haystack, Edison would examine every straw until he found the needle. Tesla, however, would design some aparatus for sensing the needle so it wouldn't be necessary to search through every straw. An example of this is when Edison was looking for something that would make an acceptable filamint in his light bulbs. He tried hundreds of things as well as ANYTHING!!! Even had expeditions bring him back bamboo, etc. Instead of reasoning out what might be a good thing to try, he simply tried everything under the sun. I believe he finally settled on tungsten? Not sure on that though. Edison only did what he did because he had several people working under him at all times. It was a joint effort. Tesla had NO ONE helping him designing his devices. Tesla's effect on the world was FAR greater than Edison's. I would like to know where Kevin Szabo got his information about Tesla sending Edison's technicians strange devices. This is new to me and sounds fascinating. Perhaps some of these are locked up somewhere. Please expand Kevin. Tesla indeed sold his patents to Westinghouse. Westinghouse himself wanted to pay Tesla, but the board of directors overuled. Tesla wanted his great work to get to the world in a usable form. So he decided to lose a fortune to give the world such technical advances. Alternating Current as we use it today is directly attributed to Nikola Tesla. The inventer of the Alternating Current Motor, Alternating Current Power Transmitting Systems, and a host of other things. Had Westinghouse paid Tesla the money promised, we would have an entirely different method of radio communication and power transmission. It would have put us another 50 to 100 years ahead in these areas. I never heard (Jim Stekas) of Edison electrocuting an elephant. I read of Edison paying kids to round up cats so he could have public demonstrations of the true dangerousness of Alternating Current by electrocuting cats in front of crouds of people. And, at the same time while Tesla would be at the World Fair, etc. passing 1, 2, or MORE MILLION volts of Alternating Current through his body while he held a glass bulb containing a metal bar. The metal bar would vaporize, but he was unharmed. Tesla NEVER used any dirty tricks on Edison. He was too good of a person. Edison, however, was a different story. If Edison had had his way, our cities would now have DC power plants spaced out about 1 mile from each other scattered all over the city. Yep, LOTS of em. And the people at the end of the DC power line would have DIM light, while the people nearest the DC POWER plant would have too bright of lights (bulbs burning out too soon also), etc. A real mess---but that's what Edison wanted. Keith Doyle: If you find out where the elephant eloctrocution footage is, please tell me. I sure never heard of this one. I have a VERY poor opinion of Edison. And this will seal my opinion. Also, for those curious about Tesla, look in your library. John J. O'neil wrote Tesla's biography and there are SEVERAL books about him. Not to mention a book devoted to showing ALL of his Patents. I believe he has over 200 of them. Some books are VERY interesting (Margaret Storm wrote another one). Tesla's Mother had NOT a photographic memory, but an audiographic one. That is, anything She heard, she could repeat. Whether or not it was in a language she understood or not. And repeated word for word, no matter how many words. She was also an inventer, which was unusual in Yugoslavia. Tesla's father was a minister, who could recite any verse in the entire Bible. Tesla himself had a total photographic memory. Anything he saw, he could remember and picture it again. After being burned a number of times by people, he stopped writing things down. After all, he had no need to really. He used to be followed by secret agents from both our country and Russia, and ?. They would pick up any scrap of paper that he might have written anything on-- when he would go to a restaurant, etc. Anywhere. He was no doubt aware of this. I have always wondered what he may have written down (diagrams, or messages, or ?). Since he no doubt knew of their presence, I bet he pulled some good tricks on them. Does anyone know if there any photographs available of Teslas's experiments in Colorado Springs (I have the Colorado Springs Notebook---it's in print for those who don't know). But I want to see some photographs of the experiments he did to generate lightning bolts in EXCESS of 100 FEET (yes, FEET). I've seen the normal 30 to 40 foot lightning bolt pictures. I want to see the HEAVY DUTY photos!! Another curious bit of information. Tesla's main technician still lives in Canada. He is the one who worked with Tesla in Colorado Springs during the Transmission of Power Without Wires experiments and the "Death Ray" experiments. He knows how to build all these things. But he is passed of as being crazy and won't show anyone anything anyway. This is because he is bitter about how the world treated Tesla. Besides, can you imagine how the "Death Ray" device would have been used? We would have had them on the borders of our country and spaced throughout the country. Tesla agreed to build one for only $2 million dollars for the government. There was one catch: It had to be used as offensive ONLY. It couldn't be made mobile. The government refused to agree---Tesla refused to build it. It would have been quite interesting to see Nuclear war averted by a device that could vaporize any missile within a 200+ MILE range. Nuclear war would be impossible with such a device---at least missiles fired at us from other countries anyway. They would be simply destroyed as soon as they got within the 200 mile range!! I suspect Tesla could have made Star Trek reality at LEAST by NOW!! Eugene C. Zinter
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (03/03/85)
> I believe [Edison] finally settled on tungsten? Nope, carbon. I don't know who came up with tungsten. > Besides, can you imagine how the "Death Ray" device > would have been used? Yup, good thing we don't have one. > It would have been quite interesting to see Nuclear war > averted by a device that could vaporize any missile within > a 200+ MILE range. It isn't that easy. I would like to see a good missile defense, but I doubt that there is a perfect one.
davet@oakhill.UUCP (Dave Trissel) (03/04/85)
In article <131@azure.UUCP> eugenez@azure.UUCP (Eugene Zinter) writes: > >I never heard (Jim Stekas) of Edison electrocuting an elephant. ....... > >Keith Doyle: If you find out where the elephant eloctrocution >footage is, please tell me. I sure never heard of this one. >I have a VERY poor opinion of Edison. And this will seal >my opinion. > I have seen a film of Edison electrocuting a large horse in New York City. I think it was on a local PBS documentary. It was so gross I'll never forget it. What about the remote control model submarine he built? That man was something else. Motorola Semiconductor Inc. Dave Trissel Austin, Texas {ihnp4,seismo,ctvax,gatech}!ut-sally!oakhill!davet
keithd@cadovax.UUCP (Keith Doyle) (03/05/85)
[......] >I would like to know where Kevin Szabo got his information >about Tesla sending Edison's technicians strange devices. >This is new to me and sounds fascinating. Perhaps some of >these are locked up somewhere. Please expand Kevin. Me too! This does sound interesting. >Keith Doyle: If you find out where the elephant eloctrocution >footage is, please tell me. I sure never heard of this one. >I have a VERY poor opinion of Edison. And this will seal >my opinion. I'll try to chase it down some more. I have the footage on video from some PBS program (not about Tesla or Edison) one of the 'Walk thru the 20th Century' I think. I'll try to dig it up and see what more I can find out. In the Tesla biographies, they definately mention he used horses, and in at least one the elephant is mentioned. I'll post what references I find. >Also, for those curious about Tesla, look in your library. >John J. O'neil wrote Tesla's biography and there are SEVERAL >books about him. O'neill's book is no longer in print, though it is probably in the library. Margaret Cheney's book 'Tesla - Man out of Time' is a more recent book, and I thought it was a little better. It's still in print. >Does anyone know if there any photographs available of Teslas's >experiments in Colorado Springs (I have the Colorado Springs >Notebook---it's in print for those who don't know). But I want >to see some photographs of the experiments he did to generate >lightning bolts in EXCESS of 100 FEET (yes, FEET). I've seen >the normal 30 to 40 foot lightning bolt pictures. I want to >see the HEAVY DUTY photos!! All I've seen are the interior shots from Colorado Springs, with Tesla calmly sitting in a chair while multi-mega-volts dance around the room. >I suspect Tesla could have made Star Trek reality at LEAST >by NOW!! Beam me up, Nikola! I've been looking for some sort of reference in Mark Twain's writings about Tesla. Since they were friends, you'd think that somewhere Twain might have mentioned him. Does anyone know of such a reference? Keith Doyle # {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd
chongo@nsc.UUCP (Landon C. Noll) (03/05/85)
In article <131@azure.UUCP> eugenez@azure.UUCP (Eugene Zinter) writes: > ... Tesla, >however, would design some aparatus for sensing the needle >so it wouldn't be necessary to search through every straw. Tesla worked on an invention from two ends, in "day dreams" and on paper. Normally, Tesla would get inspired about an idea and he would begin to dream about how it would look, feel, and be used. On the other hand he would begin to gather facts, both in experimeants (i.e. the some "aparatus" you talked about) and in theory. At first there would be a wide gap between what Tesla could prove, and what he could dream of. But as time went on, he would get more facts and his vision would become even more clear. (Tesla claimed that he knew the shape, sound, principle and usefulness of the 3-phase A/C motor in his mind years before it ever went down on paper) One day, his dream and his research would meet half way and quickly an invention would follow. What was real, law of physics, cost, etc., did not stop Tesla from dreaming. His dreams would become more real as time went on. One can see this in some of the laughable things he tried to make. Yet it was the fact that people laughed at too many of his early staged ideas that forced him to work more and more alone. Tesla said: "A fatal flaw in a dream is not a reason to quit the dream; it need to understand your dream better" >Tesla had NO ONE helping him designing his devices. This was mostly because it was hard for Tesla to explain an idea when the facts and his dreams were so far apart. By the time Tesla could explain to someone an idea and have the facts to justify it, the work was nearly (if not already) done. >I would like to know where Kevin Szabo got his information >about Tesla sending Edison's technicians strange devices. >This is new to me and sounds fascinating. Perhaps some of >these are locked up somewhere. One must be careful about some of the stories invented around Tesla. Here is an example: There is a myth given in a number of books around the fact that Tesla could make a sort of fire ball on command. This fireball was said to be about baseball sized and could last a number of seconds. The myth is in how he formed it and that it has never been duplicated. Tesla could make such things, but only in a very controlled setting. He made it look like the snap of the finger made it, but it was mearly a trigger to start up his fireball machine. What Tesla did was made what is known as St. Elmo's fire. I don't understand it very well (but then nobody does) but it has something to do with forming a magnetic knot in a high energy electric field. Folks at Sandia labs, for example, have formed similar things though not as simply as the tales of Tesla state. This is not ment to take anything away from what Tesla did, just that folks did figure out how to make such fireballs (only much later). The fireball effect can be created in nature as well. St. Elmo's fire is often seen during very high wind storms in connection with lightning. I myself saw such a thing in Oregon (1981) that lasted for nearly 60 seconds. It was a white glowing ball about grapefruit in size. It floated slowly in mid air and moved around a car for a while and then went out. >Tesla indeed sold his patents to Westinghouse. Westinghouse >himself wanted to pay Tesla, but the board of directors >overruled. J.P. Morgan (sp?) figured out how much money Tesla stood to collect in royalty from A/C power and got scared. I have heard that Tesla first had a deal where he got a 15 cents(confirm?) for every kilowatt generated from one of his A/C power plants. Morgan guessed that Tesla stood to collect close to a BILLION dollars (and these are early 1900's dollars folks!) during his life. Such a sum was seen as a threat to Morgan's power (or so Morgan thought. one wonders what Tesla would have built with the $'s) so Morgan pulled the strings on Westinghouse company to force them to buy out Tesla. > Alternating Current as >we use it today is directly attributed to Nikola Tesla. >The inventor of the Alternating Current Motor, Alternating >Current Power Transmitting Systems, and a host of other things. Don't forget the invention of radio! Books don't always show it, but Tesla won (after he already died) the first patent for a wireless communication device in a Supreme court case. (or so the story goes does anyone know more about this legal case?) >Tesla NEVER used any dirty tricks on Edison. He was too good of >a person. Tesla loved to make strange toys however. In about 1890(?) he built a radio controlled mini-sub (about 2 feet long) and had it spin around New York Harbor. Lots of folks freaked out when they saw the metal "monster". During one period he had an electric field around his law that extended for a mile or two (he once lighted 100 Watt tubes at a dist. of 50 miles with such a field). He would make little mobile "things" powered off of the field and send them off down the hill. (saw a picture of a "quasi-tank" like object the police picked up once) You might think of them as the early version of remote controlled cars. >Keith Doyle: If you find out where the elephant eloctrocution >footage is, please tell me. I sure never heard of this one. >I have a VERY poor opinion of Edison. And this will seal >my opinion. I too have seen this film. There is a major film about animal rights which shows this event, though I forget the name. I have a very poor opinion of Edison. And let me tell you, that elephant simply did not just fall over, it died in pain. > ...I have always wondered what he may have >written down (diagrams, or messages, or ?). Since he no doubt >knew of their presence, I bet he pulled some good tricks on them. The dreams of a person can be unbounded. But my guess is that we know most of what Tesla was able to actually do (see below). The loss is perhaps his dreams that others could have followed. *snif* A group that went around hounding him was the media. The early MAD scientist that one sees in a lab full of strange sounds and sparking things (Jacob ladders, dials, Tesla coils...) was patterned after his labs. Take a look at some photos on some of his labs and then look at a MAD scientist lab in an old silent film. At one time, after his public demos of how safe A/C could be, Tesla got hooked up in showmanship. He got thrills out of playing the role of an "electrical magic showman". He later had to hind himself away when people began hounding him for his stage shows. This period in Tesla's life did not help his "MAD scientist" image. It is also a period from which many mythical stories written by unknowing reporters were generated. > ... the "Death Ray" experimeants. He knows >how to build all these things. But he is passed of as being >crazy and won't show anyone anything anyway. This is because >he is bitter about how the world treated Tesla. ... It is my guess that the Tesla "Death Ray" was built around the formation of St. Elmo fireballs under very high power at long dist. One would think that such a device would be easy to defeat and/or defend against. Anyone have a guess as to what it might have been? chongo <zappppp> /\ee/\ -- If Tesla had been born in the early 60's, he might have been the builder of desk top Cray-VI like computers running a super 4.9BSD like operating system. Edison on the other hand, would have searched by trial and error for the ultimate 4004 based j-random spread sheet micro while claiming that the power of the Tesla machine could kill a programming project. Worse yet, historians might later credit Edison with forming the personal computer industry.
chris@umcp-cs.UUCP (Chris Torek) (03/05/85)
I think you've confused St. Elmo's fire with ball lightning. St.
Elmo's fire is merely corona discharge, easily demonstrated with a
small HV coil and a sharp object. Electrons will ``spray'' off the
point of a pin attached to a Tesla coil, for example. (I have a
four-foot secondary wrapped with AWG30 wire I used to play with...)
--
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
UUCP: {seismo,allegra,brl-bmd}!umcp-cs!chris
CSNet: chris@umcp-cs ARPA: chris@marylandfowler@uw-beaver (Rob Fowler) (03/06/85)
I posted something on this to net.rumor, but since Tesla came up again ... One of the things that Tesla was into was power transmission by novel means. Fer instance, apparently a lot of the stuff in the Colorado Springs lab had portable power supplies consisting of secondary coils coupled to the huge primary that surrounded the building. Another scheme that he experimented with was long distance power transmission (AC) using a single phase and a single wire and using the Earth as the return path. I've heard and read about these experiments in several places, but don't really know anything about the results. Using ground loops is something I've been trained to avoid. About 6 or 7 years ago there were a couple of really bad years of Winter weather in North America. The jet stream had wandered all over the place. The Northwest was relatively dry and sunny. There was speculation about "power droughts" (enough to drink, but not make electricity). The Midwest and East were extremely cold and were getting hit by blizzard after blizzard. In the midst of this there was an employee (a "scientist" of undetermined vintage and credentials) of the National Research Council of Canada who managed to get the Canadian press to print his version of what was going on. To paraphrase it: It was just another nefarious plot by those damn Russkies!!. They had been studying Tesla's work initially because they were interested in communicating with their submarines. The idea was to avoid using a special purpose system (like Project Sanguine in Wisconsin) by using (parts of) their existing power grid as an antenna. By unbalancing the power grid you can somehow create a ground current that is somehow detectable by a submerged sub. Well, we don't know how successful they were at communication, but they apparently detected some climate modification. Aha!! says some commisar, we will wage economic warfare!. We jack around our power grid, this pushes global air currents off their normal courses, warm moist air is sucked up over the Ukraine thus causing bumper crops, cold Arctic air is pushed off of the North Pole into the middle of North America causing all kinds of suffering, and finally, the winter long low pressure systems that usually hang around off the British Columbia coast head South and flood California!! A despicable, but brilliant, plan! This guy from NRC wound up getting the ear of several reporters over the course of two or three years. As I recall, he was explaining North American inaction on his theory by saying that although the governments recognized the correctness of his position that they had no reasonable form of retaliation prepared. After all, we couldn't just tell them to stop screwing around with our weather or it's "Nuke City". So much for the theory. I'd stumbled across these articles in the Canadian popular press up until '78 when I left Vancouver. Since then I've seen nothing. A couple of years later I happened upon some of the Tesla biographies/hagiographies, but they are pretty non-technical. This leads to a couple of questions (discussion topics): What exactly was Tesla doing w.r.t. power transmission and/or communication using ground returns? His tower on Long Island was going to use this, but how? Marconi had heard of Hertz and Maxwell and used the theory of electromagnetic waves. Tesla's tower seems to be to be a kludge left over from an earlier, pre-EM era. (I recall mention of very low bandwidth and using the entire Earth/atmosphere system as a resonator. Not so good for Hi-Fi, but Ok for calling subs?) What are the power transmission aspects of this? Does anyone else out there recall anything about the guy in Ottawa and his weird rantings? Does he still work for NRC? Is there any scuttlebutt about these rumors, theories, accusations? -- Rob Fowler ( ... uw-beaver!fowler or fowler@washington.arpa)
wb@hou4a.UUCP (W.Baumgartner) (03/06/85)
I have been reading the discussion about Tesla with great interest. Some of his experiments have always facinated me, in particular the Tesla Coil. I was wondering if anyone out there knows where I can find the plans to build one using modern components such as transistors, flyback transformers (from TV) etc.etc. I do not relish the task of winding my own coils. Any information would be appreciated (I would like BIG sparks) Thanks, Werner B. AT&T-IS Holmdel, NJ
keithd@cadovax.UUCP (Keith Doyle) (03/07/85)
[........] >Don't forget the invention of radio! Books don't always show it, but >Tesla won (after he already died) the first patent for a wireless >communication device in a Supreme court case. (or so the story goes >does anyone know more about this legal case?) I do know that the court case did decide that Tesla, and not Marconi is now credited with the first invention of radio. Teslas knowledge of resonance has not been equaled since. >Tesla loved to make strange toys however. In about 1890(?) he built a >radio controlled mini-sub (about 2 feet long) and had it spin around >New York Harbor. Lots of folks freaked out when they saw the metal >"monster". Unfortunately, much of the response was of the sort 'OBOY, we can put a BOMB in it and BLOW ships up!'. I think Tesla was a little disappointed that this was perceived as the most significant aspect of this type of technology. Another one of his strange toys was a compressed air operated 'tapping' or vibrating device which he demonstrated could be used to build up a resonant wave in buildings to the point that they could be demolished. During one of his experiments with this device on a piling in the basement of one building the surrounding buildings began to build up waves first, before Tesla realized he was having any effect as the building he was in had not started to react yet. He was quite surprised when some of the local gendarmes burst in just as the building he was in did start to react, as he had just noticed these effects himself moments ago. We can credit Tesla with AT LEAST the following inventions: 1. A.C. motors, generators, transmission systems 2. Radio transmission 3. Fluorescent Lighting and the Neon Sign 4. First radio controlled devices And perhaps he should be credited with others, such as possibly the discovery of X-Rays (not by that name however) , or perhaps the artificial generation of X-Rays. And, I'm sure there are others. > ...I have always wondered what he may have >written down (diagrams, or messages, or ?). Since he no doubt >knew of their presence, I bet he pulled some good tricks on them. Some of his writings are quite readable. He published several articles in Electrical Experimenter in the 1910-1920 era, in a column called 'My Inventions'. BY the way, there is a unit of measurment called the 'Tesla' but I forgot for the moment what it's for. Anyone remember? Keith Doyle # {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd
keithd@cadovax.UUCP (Keith Doyle) (03/09/85)
[............] >I have been reading the discussion about Tesla with great interest. >Some of his experiments have always facinated me, in particular >the Tesla Coil. I was wondering if anyone out there knows where >I can find the plans to build one using modern components such >as transistors, flyback transformers (from TV) etc.etc. >I do not relish the task of winding my own coils. >Any information would be appreciated (I would like BIG sparks) > Thanks, Werner B. AT&T-IS Holmdel, NJ I'll give this one a try. There are plans out there for coils, you might check the readers guide at a local library. I once found a Popular Science/Mechanics/Electronics article that used a T.V. HV regulator tube as driver for an oscillator. Although you indicated you're not crazy about coil winding, I found that it really wasn't all that bad. I used a bolt in one end of my coil form and put it in the chuck of a variable speed hand drill, and anchored the other end so it would turn. With a buddy on the drill, I wound my coil in about 1/2 hour. If anyone knows of the source of some less crude (than my following instructions) yet accesible method of constructing coils, I'd like to hear about it too. My present coil is constructed using a 15000v neon sign transformer. Check for local neon sign repair outlets in your area. You can usually obtain used sign transformers fairly cheap ($10-$20). CAREFUL, 15000v is a lot of juice, and mine will deliver 60ma (30 is also common). These come in about a 3x4x10 size package that weighs 30lbs or so, with large ceramic insulators on either end. Just plug one into 115v, and instant 15kv. ALso watch that the center tap of the transformer may be connected to the metal case of the transformer, which means that either insulated end (or your resulting coil) are a good 7.5kv hot with respect to this transformer case. Next you need a H.V. capacitor. I initially went to a glass shop, and had them cut me about a dozen glass tiles 1 foot square, out of 1/4 inch glass. You can home make a H.V. cap by layering glass and aluminum foil in a stack. Every other aluminum layer should be connected together on one side, and the leftover layers on the other. Make sure that you have plenty of margin between the end of a sheet and the side it's NOT connected to, as 15kv will jump a couple of inches easy. Illustration: --> |--------------------| plenty of margin | glass | --> | |----------| | | | | | 15kv worth | | | | | | foil | | | | | | | | | | | | | | |----|---| |---|----| | | ^ ^ |\----- connection here | | 7.5k worth of margin basically, you can just contstruct one of these for each sheet of glass you have, and then pile them up so that every other one is rotated 180 degrees. Connect all of the connection points on either end together, and you have a H.V. capacitor. Note that you can make them bigger than 1 foot square, I found that I needed so much margin that the foil area was fairly small, and didn't deliver much capacitance. Thinner glass might work too, but you're depending on the thickness of this glass to insulate to the full 15k. I feel the more capacitance the better, as it keeps the frequency of the resultant coil down to a signal that is more effective and carries more 'punch'. After my first glass cap, I was later able to find a surplus oil-filled H.V. cap which GREATLY improved the efficiency of my coil. Unfortunately these have been hard to find. (I'd grab another if I found one). I used Scotch tape to anchor the foil to the glass. Ok. Now on to the coil. I used a 2-1/2 to 3 inch mailing tube. Larger tubes are certainly workable, but I didn't have a lot of space, and the tube was handy. Smaller ones probably work too, you can certainly get more turns/ratio on a smaller core. You probably want a tube that is at least a couple of feet long. The next step is to buy a load of enameled magnet wire. Basically, you just start winding from one end to the other, or until you run out of wire (splicings ok, but be neat!). The voltage step-up ration of your coil is theoretically the number of turns in the secondary divided by the number of turns in the primary (haven't got to the primary yet). Realistically, I have no idea how to compute the practical ratio as there are losses all over the place in a kludge like this. At any rate, use your own judgement, generally, the more turns the better. I would suggest that you wrap cleanly, and don't over-wrap previous turns. There are ways of over-wrapping such coils, but I don't know what they are, and you don't want the coil to arc accross the windings. When you're done winding, you might want to consider some kind of fixative process. Some people boil the whole thing in wax, I just anchored the ends, and painted them with corona-dope (an insulative paint that you can get at local T.V. repair oriented electronics shops). It's not necessary to do either, but it may cut down on inter-coil (?) emmisions. Ok, now we need the primary. I used very-few turns of a T.V. H.V. wire (I think 6 turns), and just wrapped it on the base of my secondary coil as if it was a continuation of it's windings. The resonant frequency of the coil is related to the number of turns in the primary and the capacitance of the H.V. cap. So few turns and so little capacitance tend to run at frequencys so high that the efficiency of the coil is not that great. You can improve efficiency by adding more primary turns but this will drop the turns-ratio you worked so hard to get for that H.V. It would be better to use more capacitance to bring the resonant frequency down to more efficient ranges. You don't have to use H.V. wire for the primary, just about anything will work. An earlier coil of mine just used some medium gauge solid wire insulated to 600 volts. The voltage difference from one winding to the next is not enough to worry about. Lastly, you need a spark gap. I used a couple of peices of heavy gauge wire mounted in a plastic box so that they are insulated from each other. I've heard of people using lead pencils mounted with the points facing each other, and using the lead as the conductor, but I've never tried that. You want to position whatever you use as conductors so that they never come closer than about 1 inch at any point (for 15kv anyway, lower voltages you may have to position closer). I mounted mine in an enclosed plastic box, because when the sparks fly, it makes ALL KINDS of NOISE, and emits ALL KINDS of OZONE (operate in well ventilated area). Ok, now lets see if I can draw a schematic: (----> output ( ( ( secondary windings ( ( ( ( ( (---------------| primary windings ( | (----| ===== capacitor | | | | spark gap +---> <---+ | | | | ~~~~~~~~~~~~ neon sign transformer # #============< from 115v A.C. ~~~~~~~~~~~~ (whew!) That's about it. All sorts of substitutions can be made, you might try using a car coil instead of a neon transformer as a driver, (I've seen circuits that use an SCR and a little neon glow light that smack a car coil with 115v for turning flouorescent tubes into strobe lights, the coil can get a little hot, you might try a lower-voltage oscillator circuit to drive the car coil). You can play with all the parameters, capacitance, size of coil, number of turns, etc. to try to get a more efficent coil. I noticed, for instance, that if you use a fan to blow over the spark gap, it's extra agitation works to improve efficiency, some schemes use a rotating disk with holes in it to 'interrupt' the circuit more often which helps. Basically, the spark gap serves to generate high frequency 'glitches' that exite the coil, as only the high frequency components of the signal into the primary actually goes through the coil. The capacitor takes these 'glitches' and by working as a tuned circuit with the primary windings, serve to sustain oscillation at these high frequencys. What can you do with it now that you've made one? Well, besides fouling up all the T.V.'s in the neighborhood, and amazing your friends, the coil will exite the gas in any fluorescent tube held within a couple of feet of the coil, and other than that, I can't think of anything right now. Some of my Tesla books indicate experiments with light pieces of wire hung of the secondary that emit sparks and spin around, etc. Note that because of the spark gap, the thing is VERY noisy, and the gap itself emits more light than the secondary (another good reason why I hid it in a plastic box). Any more questions about this one, address them to me. And if anyone has further suggestions for improvements, I'd like to hear them. About once every 6 months I drag the thing out and start it up, and think about what I might do to improve its efficency, or quiet it's noise etc. (mine puts out about 10-inch sparks) This was inspired by a coil that was in my High-School electronics class, a slightly larger model that would produce sparks of 1-1/2 to 2 feet long, with basically the same design but a larger coil and capacitor. I don't have much access to machine shop tools etc, and didn't have a lot of space for storage, so I kept mine rather small. Have fun, and don't electrocute yourself. Keep in mind that the 15kv primary is a lot more dangerous than the secondary emmisions. If you get zapped by the secondary, chances are it will do little more than curl your hair or give you a tickling sensation, but 15kv could knock you around the room! Keith Doyle # {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd
josh@v1.UUCP (Josh Knight) (03/12/85)
> BY the way, there is a unit of measurment called the 'Tesla' but I forgot > for the moment what it's for. Anyone remember? > > Keith Doyle > # {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd magnetic field, 1 gauss = 0.0001 tesla (try asking units, it knows). Josh Knight, IBM T.J. Watson Research josh at YKTVMX on BITNET, josh.yktvmx.ibm on CSnet, ...!philabs!v1!josh
friesen@psivax.UUCP (Stanley Friesen) (03/12/85)
In article <2436@nsc.UUCP> chongo@nsc.UUCP (Landon C. Noll) writes: > > > ... the "Death Ray" experimeants. He knows > >how to build all these things. But he is passed of as being > >crazy and won't show anyone anything anyway. This is because > >he is bitter about how the world treated Tesla. ... > >It is my guess that the Tesla "Death Ray" was built around the formation >of St. Elmo fireballs under very high power at long dist. One would think >that such a device would be easy to defeat and/or defend against. > > >Anyone have a guess as to what it might have been? > > My guess would be some sort of high-power laser. -- Sarima (Stanley Friesen) {trwrb|allegra|cbosgd|hplabs|ihnp4|aero!uscvax!akgua}!sdcrdcf!psivax!friesen or {ttdica|quad1|bellcore|scgvaxd}!psivax!friesen
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (03/17/85)
> My guess would be some sort of high-power laser.
Now you're telling me that Tesla figured out quantum optics...jlg@lanl.ARPA (03/20/85)
> >It is my guess that the Tesla "Death Ray" was built around the formation > >of St. Elmo fireballs under very high power at long dist. One would think > >that such a device would be easy to defeat and/or defend against. > > > > > >Anyone have a guess as to what it might have been? > > > > > My guess would be some sort of high-power laser. There is no indication in the works of Tesla or in the reports of any of his biographers that he had either the theoretical or the practical knowledge required to build a laser. Lasers only work because of quantum mechanics, which Tesla had no knowledge of either. Tesla was severly underrated in his time, but this does not imply that he knew EVERYTHING. J. Giles
hes@ecsvax.UUCP (Henry Schaffer) (08/23/85)
<> The Denver Museum of Natural History has a demonstration/show several times a day called "ZAP" which has a Tesla coil as its main ingredient. It is fed by 15,000 VAC (at 1 amp) and can produce sparks of 2 million volts which jump over 5 feet, produce nice loud noises and a strong smell of ozone. There is a series of demonstrations, including handing out floursecent tubes to the audience, which holds them vertically while the coils sends out sparks (lightning bolts!), and the tubes glow. I was clearly involved in the current flowing through the tube (as a result of the EM field) because when I moved my hand further up the tube only the portion above my hand glowed strongly, below my hand it was relatively dark. (They warn people with pacemakers, etc. against attending.) One exciting demo was having a volunteer get inside an on-stage cage made of hardware cloth (about 1/2" squares) and shooting 2 million volt sparks at it, proving the effectiveness of the Faraday cage. I was there, in the cage, and it did work! The flourescent tube I held stayed dark, and I felt no electrical sensations at all - just light, noise and ozone. The show is supposed to continue through September. They pointed out that Tesla had a lab in Colorado Springs for a couple of years, and also mentioned that the museum bookshop had several books on Tesla. I bought "My Inventions", the autobiography of Nikola Tesla (published by Hart Brothers in 1982), and it is quite readable, but doesn't give much technical explanation. --henry schaffer n c state univ
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (08/25/85)
> They pointed out that Tesla had a lab in Colorado Springs for a > couple of years, and also mentioned that the museum bookshop had > several books on Tesla. I bought "My Inventions", the autobiography > of Nikola Tesla (published by Hart Brothers in 1982), and it is quite > readable, but doesn't give much technical explanation. Tesla's Colorado Springs notes, with additional annotations by a commentator, were published in book form in Bulgaria. I have a copy (found it in a rare book shop).
hes@ecsvax.UUCP (Henry Schaffer) (08/27/85)
> > They pointed out that Tesla had a lab in Colorado Springs for a > > couple of years ... > Tesla's Colorado Springs notes, with additional annotations by a > commentator, were published in book form in Bulgaria. I have a > copy (found it in a rare book shop). This sound like a book I saw in the Denver Museum of Natural History bookshop. Title: Colorado Springs Notes 1899-1900. Author: Nikola Tesla, with commentary by Aleksandar Marincic. Publisher: Nolit Beograd, Terazije 27, Yugoslavia. 1978 In English. $40.00. It is hardbound, 8 1/2" by 11", and close to an inch thick, and looked quite interesting - but I didn't buy a copy. --henry schaffer
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (08/29/85)
> This sound like a book I saw in the Denver Museum of Natural History > bookshop. Title: Colorado Springs Notes 1899-1900. Author: Nikola > Tesla, with commentary by Aleksandar Marincic. Publisher: Nolit > Beograd, Terazije 27, Yugoslavia. 1978 In English. $40.00. > It is hardbound, 8 1/2" by 11", and close to an inch thick, and looked > quite interesting - but I didn't buy a copy. Oops, I meant Yugoslavia. Thanks, Henry. I forgot to mention that it includes several photgraphs of Tesla's apparatus in operation. Nice long sparks.. I believe that some fool allowed Yugoslavia to carry away much of Tesla's notes and equipment after his death, even though he was a naturalized American citizen.