Date: 06-01-94 17:15 From: Richard Quick To: Bruce Ratcliffe Subj: electronics project ideas ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ AS| Does anyone have any suggestions as to where I could find AS| plans or a book on building a small tesla coil? ... AS| (not a) monster, just a small scale coil that would make a AS| good summer project. DH> Hi Andrew - I don't know of any books that give hands-on DH> construction plans but there are several people here who DH> are active. I friend of mine is building a "tabletop" coil DH> 3" diameter, 12" long... DH> You will need to collect some neon sign transformers DH> (12-15Kv), build a spark gap, put together a capacitor and DH> wind the primary and secondary coil. I just passed this along if you are interested. R.Q. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 17:52 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ You were posting this to Blair Groves, but I finally succumbed.. AS> (hence the burning of fossil fuels that destroy the ozone AS> layer) From what I have read it is chloroflorocarbons that have been firmly identified as responsible for atmospheric ozone depletion, products such as "freon" used in the chillers of air conditioning systems and propelents in spray cans. AS> I heard that Tesla himself build a 10 story coil that was AS> capable of lighting up bulbs 20 miles away.... The tower of the Wardenclyffe commercial plant built in 1901 was 167 feet tall (air terminal) on a stone and concrete foundation that exended 50 feet below the water table (the ground terminal). The power station built near the tower had footings poured for four massive multi-phase generators to drive what at the time was the largest capacitor bank in the world. The coil was steam powered, with one boiler and generator operational. AS> ... (the coil) caused all the corn fields within a 20 mile AS> radius to spontaneously combust :) -Andrew Nothing like this ever occured, though many of the effects of his oscillators were even stranger. He experimented with mechanical, and electromechanical, oscillators in addition to the purely electrical devices such as the Tesla coil. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-01-94 06:48 From: Bob Patten To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ AS> Does anyone have any suggestions as to where I could find AS> plans or a book on building a small tesla coil? (Is this a AS> stupid question?) I really don't want a monster, just a small AS> scale coil that would make a good summer project. How about an ignition coil using a K-Mart universal coil (abt $12) and a 555 timer chip? Makes about 40KV, easy to build, and cheap. For an S.A.S.E., can copy the book and send it to you. Bob Patten 2841 N.W. 112 Terrace Plantation, Fl. 33323 ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-02-94 07:10 From: Bob Patten To: All Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ I'm interested in building a Tesla coil using a ham transmitter as the power source (if it's possible). The lowest frequency available to me is 1.8Mhz at 100w or 3.5Mhz at 1000w, both at an impedance of 50 ohms. I know that the conventional Tesla coils with spark gaps operate at much lower frequencies. Does anyone have any experience in this area? ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 00:17 From: Michael Diresta To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Richard, hope it's ok to jump in. Many years ago (30) I built a Tesla Coil for a school project. The unit got packed up and put away. After seeing so many messages here it renewed my interest. I unpacked it and although it looks perfect it don't work. I never saved the schemetic and haven't a clue where to find one. I do remember that it came out of a Popular Science/Mech mag back in the 60's. The unit has from memory a 30" coil of # 32 wire that I wound by hand on a wooden Dowel. There a big transformer, can't remember where I found it and a smaller 6.3V transformer used to run two 611A tubes. There are also a couple of barrel type caps that I got from an old B/W TV set, a couple of switches one of each transformer and a few other parts. Have you any ideas where I should start?? ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 11:15 From: Andrew Sempere To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >monster, just a small scale coil that would make a >good summer project. BP> How about an ignition coil using a K-Mart universal coil BP> (abt $12) and a 555 timer chip? Makes about 40KV, easy to BP> build, and cheap. For an S.A.S.E., can copy the book and BP> send it to you. BP> Bob Patten BP> 2841 N.W. 112 Terrace Great! I'll send you an SASE ASAP Thanks! -Andrew ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 11:29 From: Dave Halliday To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DH> I friend of mine is building a "tabletop" coil - 3" DH> diameter, 12" long. You will need to collect some neon sign DH> transformers (12-15Kv), build a spark gap, put together a DH> capacitor and wind the primary and secondary coil. Key DH> thing with coils - stay away from PVC pipe AS |Thanks for the help, a 3 X 12 sounds like a good size... Hi Andrew - I saw that Richard QUick also responded to your question - he has a lot of great information that he has posted. I was initially interested in Tesla Coils back when I was in High School and built one along the "classical" lines and was very disappointed with the results. The "classical" school of thought then was to go for a long skinny secondary, just a few turns on the primary and a large capacitance. This turns out to be 150% wrong! You need a short squat secondary, about 5-15 turns and a smaller capacitance for optimal performance. The secondary should be about 1:4 ratio dia to height. ! Origin: Grey Matter * Seattle, WA * (206) 528-1941 (1:343/210) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 18:37 From: Roy J. Tellason To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 30 May 94, Andrew Sempere writes to All: AS> Does anyone have any suggestions as to where I could find AS> plans or a book on building a small tesla coil? (Is this a AS> stupid question?) I really don't want a monster, just a AS> small scale coil that would make a good summer project. Some years ago there were a couple of articles published on this in Popular Electronics. One was about 3 or 4 feet tall, and would generate anywhere from 250,000-750,000 volts depending on how many glass-plate capacitors you added to it. The other was a somewhat smaller unit which sounds like it would be what you're looking for. If anyone out there has a copy of this magazine, I'd sure love to get copies of the articles again, I lost my copy of it years ago... That big one would light a flourescent tube 6 feet away with no wires! ! Origin: TANSTAAFL BBS (1:270/615) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 00:24 From: Andrew Sempere To: Richard Quick Subj: 10KVA TESLA COIL ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ * Original From: Norman Cardillo (1:324/114) * Original To : Andrew Sempere (1:324/114) Somebody once said that power should be transmitted with Tesla Coils instead of using wires, because those wires running every- where cause a health problem. This would probably cause more problems than transmission lines. ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-04-94 00:37 From: Terry Smith To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BP> I'm interested in building a Tesla coil using a ham BP> transmitter as the power source (if it's possible). BP> The lowest frequency available to me is 1.8Mhz at 100w BP> or 3.5Mhz at 1000w, both at an impedance of 50 ohms. BP> I know that the conventional Tesla coils with spark gaps BP> operate at much lower frequencies. Does anyone have any BP> experience in this area? You could quite easily turn a Tesla coil into a transmitter, generating signal types not approved for HAM use, at strengths well above Part 15 limits. Below 9 kHz such limits would not apply. Other than by only operating it well inside the boundaries of a BIG piece of private property, I wonder what kind of induced and radiated signal strenghts are produced by large Tesla coils. I'd guess that what sounds like a 50 KVA unit discussed here probably substantially exceeds Part 15 unintentional radiator emmissions limits. If Richard, or the others playing with toys, notice... Over what range of frequencies are you guys producing emmissions, and at what kind of field/distance? I'd imagine some coils produce an unstable (in terms of frequency) output over a 10 or 100 to 1 range, while others may be stable within 5% or less. Is this a reasonable presumption? Have any of these coils been monitored with field strength meters, or spectrum analyzers with calibrated antenna sets? Terry ! Origin: Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 00:26 From: Andrew Sempere To: Dave Halliday Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DH> I was initially interested in Tesla Coils back when I was in DH> High School Sounds like me... I always thought I was the only DH> high school kid who thought that building a tesla coil might DH> be fun... Oh well :) DH> and built one along the "classical" lines and was very DH> disappointed with the results. The "classical" school DH> of thought then was to go for a long skinny secondary, DH> just a few turns on the primary and a large capacitance. DH> This turns out to be 150% wrong! You need a short squat DH> secondary, about 5-15 turns and a smaller capacitance for DH> optimal performance. DH> The secondary should be about 1:4 ratio dia to height. Thanks for the tips, as I am entirely new to Tesla coils, anything is helpful, this promises to be quite interesting... -Andrew ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 00:29 From: Andrew Sempere To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RJT> Some years ago there were a couple of articles RJT> published on this in Popular Electronics. One was RJT> about 3 or 4 feet tall, and would generate anywhere RJT> from 250,000-750,000 volts depending on how many glass- RJT> plate capacitors you added to it. The other was a RJT> somewhat smaller unit which sounds like it would be RJT> my copy of it years ago... I think I'm going to check my local library, they offer a service that can fax a copy of almost any article you want for a small charge, I used it to get a few other old Popular Electronics articles. If I find it I'll let you know (If you want a copy just let me know) Anyway, thanks for the note -Andrew RJT> That big one would light a flourescent tube 6 feet away RJT> with no wires! Cool! 8-) ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 18:25 From: Richard Quick To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Bob Patten to All <=- BP> I'm interested in building a Tesla coil using a ham BP> transmitter as the power source (if it's possible). There are at least two ways that I can think of to run a coil from a driver such as this. But I would not advise doing it. The ham equipment, powerful as it is, is not designed to drive a coil to spark. You would be better (and it would be much safer for the HAM xmittr) to design a tube driven or spark gap excited tank circuit to drive a coil. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 18:25 From: Richard Quick To: Michael Diresta Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Michael Diresta to Richard Quick <=- MD> Richard, hope it's ok to jump in. We love to jump in! MD> Many years ago (30) I built a Tesla Coil for a school MD> project. The unit got packed up and put away. After MD> seeing so many messages here it renewed my interest. I MD> unpacked it and although it looks perfect it don't work. I MD> never saved the schemetic and haven't a clue where to find MD> one. I do remember that it came out of a Popular MD> Science/Mech mag back in the 60's. The unit has from memory MD> a 30" coil of # 32 wire that I wound by hand on a wooden MD> Dowel. There a big transformer, can't remember where I found MD> it and a smaller 6.3V transformer used to run two 611A MD> tubes. There are also a couple of barrel type caps that I MD> got from an old B/W TV set, a couple of switches one of each MD> transformer and a few other parts. Have you any ideas where MD> I should start?? I will start by telling you that I am not an expert on tube coils; though I am familiar with them, I have never designed or built one. With that out of the way, I will let you know what I can, and reference the rest. Most likely the project you are looking at was titled "Lil' Tesla Coil",(or somesuch), and was built by a lot of Popular Science readers of the era. The design is so dated by modern standards that I would scavenge the tubes, caps, and power supply; the rest I would scrap and rebuild. The reasons for this are nearly too numerious to list... 1) Wood is at the bottom of the list of suitable coil form materials. This coil should be wound on acrylic, polyethylene, polystyrene, polypropylene, or some other high Q plastic. 2) The wire (#32) is too thin for excellent efficiency. Move up to #24, or larger, double Formvar covered magnet wire. 3) The coil form is too skinny; it needs to be fatter for a higher inductance, higher Q coil, using the heavier wire. The new plastic secondary coil should have an aspect ratio (height to width ratio) of no more than 4:1, 3:1 being close to ideal. 4) The primaries need to be rebuilt to match the new higher Q secondary design. Greater surface area conductors (thin wall pipe, coax shield, strap, strip, etc.) should be substituted for the solid bare copper wire typically used on early tube coils. By far and away the most exhaustive reference on tube circuits was done by James and Kenneth Corum and is titled "VACUUM TUBE TESLA COILS", published by Corum & Assoc, 8551 State Route 534, Windsor, Oh. 44099, available from the International Tesla Society, P.O. Box 5636, Colorado Springs, CO. 80931. A second book that features what I believe is the same or similar coil is "Tesla Coils! 100 Years of Electrical Magic" by Brent Turner, and most likely available at the address above. Mr. Turner's book has a lot of info on the solid state drivers for inductively coupled Tesla coils. His coil is a historical reproduction of the tube coils popularized in the 60's. Harry Goldman at The Tesla Coil Builders Association will have additional book sources: TCBA, 3 AMY LANE, QUEENSBURY, NEW YORK 12804. (Tell him I refered you) This will get you started, if you need any more help please let me know. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 23:34 From: Andrew Sempere To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> From what I have read it is chloroflorocarbons that have RQ> been firmly identified as responsible for atmospheric ozone RQ> depletion, products such as "freon" used in the chillers of RQ> air conditioning systems and propelents in spray cans. I suppose that I really was rolling two issues together: Ozone depletion and global warming. One of the biggest "greenhouse gasses" is carbon dioxide, a result of combustion, while the ozone aspect is mainly the result of CFC's... RQ> The tower of the Wardenclyffe commercial plant built in 1901 RQ> was 167 feet tall (air terminal) on a stone and concrete RQ> foundation that exended 50 feet below the water table (the RQ> ground terminal). Wow :) Sounds like a very large, very expensive project. Incidentally, was it ever operational? AS> ... (the coil) caused all the corn fields within a 20 mile AS> radius to spontaneously combust :) -Andrew RQ> Nothing like this ever occured, though many of the effects RQ> of his oscillators were even stranger. He experimented with RQ> mechanical, and electromechanical, oscillators in addition RQ> to the purely electrical devices such as the Tesla coil. Too Bad... I heard the story at an electricity demonstration using a three story Van de Graph generator, a tesla coil, and a few other devices at the Boston Museum of Science. While I had my doubts, the image of exploding cornfields amused me... Oh Well... -Andrew ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 19:36 From: Richard Quick To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Bob Patten <=- BP> I'm interested in building a Tesla coil using a ham BP> transmitter as the power source (if it's possible). BP> The lowest frequency available to me is 1.8Mhz at 100w or BP> 3.5Mhz at 1000w, both at an impedance of 50 ohms. BP> I know that the conventional Tesla coils with spark gaps BP> operate at much lower frequencies. Does anyone have any BP> experience in this area? -=> Sez Terry Smith to Bob Patten <=- TS> You could quite easily turn a Tesla coil into a transmitter, TS> generating signal types not approved for HAM use, at TS> strengths well above Part 15 limits. Below 9 kHz such TS> limits would not apply. He wants to drive a coil with xmitr outputs, not set up a coil to mimic xfrmr output (ie make a transmitting Tesla Coil). There is a big difference in making a coil transmit, and making a transmitter drive a coil to spark. TS> Other than by only operating it well inside the boundaries TS> of a BIG piece of private property, I wonder what kind of TS> induced and radiated signal strenghts are produced by large TS> Tesla coils. I'd guess that what sounds like a 50 KVA unit TS> discussed here probably substantially exceeds Part 15 TS> unintentional radiator emmissions limits. The only large coil I have heard discussed here is mine, and it is 10 KVA (where did 50 KVA come from anyway?) coil. As for induced and radiated signal strengths... Oh there is some, I won't deny it. Up close the field strength will damage modern electronics. But my REAL emmissions are neglible, most everthing I generate goes to ground. TS> If Richard, or the others playing with toys, ^^^^ I love this guy! TS> notice... Over what range of frequencies are you guys TS> producing emmissions, and at what kind of field/distance? TS> I'd imagine some coils produce an unstable (in terms of n TS> frequency) output over a 10 or 100 to 1 range, while others TS> may be stable within 5% or less. Is this a reasonable TS> presumption? Uh, yeah I guess so... TS> Have any of these coils been monitored with field strength TS> meters, or spectrum analyzers with calibrated antenna sets? Oh, man... You put a calibrated antenna set anywhere within 50-60 feet of one of my experiments and you are going to instantly fry some real expensive equipment. Spectrum anyalizer??? I can usually measure field strength with volt/ohm meter, and I register on the volts scale, (not milivolts) with a resistor and rectifier in the probe antenna. Better yet, just grab the closest tube with any vacuum in it, does it glow bright? Yup, the coil is firing..... Of course, whether or not I am causing anybody any problem is another, completely different, story. My equipment is responsibly built and operated. I have had ZERO complaints about RFI, and I have checked. My biggest complaint? My sparkgaps sound like unmuffled chainsaws, and people complain about the noise... ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 05:13 From: Bob Patten To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> BP> How about an ignition coil using a K-Mart universal coil -> BP> Makes about 40KV, easy to build, and cheap. -> BP> S.A.S.E., can copy the book and send it to you. -> BP> Bob Patten -> BP> 2841 N.W. 112 Terrace -> Great! I'll send you an SASE ASAP Thanks! -Andrew I think you'll have fun with it! You can get all the other parts at your local Radio Shlock and the whole project won't cost you a ton of time or money... 73, BP ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 18:47 From: Roy J. Tellason To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 02 Jun 94, Bob Patten writes to All: BP> I'm interested in building a Tesla coil using a ham BP> transmitter as the power source (if it's possible). Why would you want to do that? TANSTAAFL BBS (1:270/615) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 19:16 From: Roy J. Tellason To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 05 Jun 94, Andrew Sempere writes to Roy J. Tellason: RJT>> Some years ago there were a couple of articles published RJT>> on this in Popular Electronics. One was about 3 or 4 feet RJT>> tall, and would generate anywhere from 250,000 -750,000 RJT>> volts depending on how many glass-plate capacitors you RJT>> added to it. The other was a somewhat smaller unit which RJT>> sounds like it would be my copy of it years ago... AS> I think I'm going to check my local library, they offer a AS> service that can fax a copy of almost any article you want AS> for a small charge, I used it to get a few other old Popular AS> Electronics articles. If I find it I'll let you know (If you AS> want a copy just let me know). Great! Sorry I can't be more specific about what issue it was in, or even the year. I'd say that the odds are pretty good that it was 1965 or earlier, if I had to take a guess. Yeah, if you get this let me know what it amounts to and I'll get back to you about copies, etc. ! Origin: TANSTAAFL BBS (1:270/615) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 02:41 From: Bob Patten To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BP> I'm interested in building a Tesla coil using a ham BP> transmitter power source (if it's possible). The lowest BP> frequency available is 1.8Mhz at 100w or 3.5Mhz at 1000w, BP> both at an impedance of 50... I know that the conventional BP> Tesla coils with spark gaps operate lower frequencies. BP> Does anyone have any experience in this area -> You could quite easily turn a Tesla coil into a transmitter, -> generating types not approved for HAM use, at -> strengths well above Part 15 limits. Below 9 kHz such limits -> would not apply. Well, in my case, I could always key it and make some CW QSO's whilst demonstrating the effects of the Tesla coil. I imagine it would radiate a clean CW signal... ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 19:57 From: Randy Dixon To: Andrew Sempere Subj: Tesla coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ I knew a Guy whom made one and lit up a guy 2 houses down whom was using his telephone, so please be careful when testing these toys... Randy ! 1.58/004124 Pleasure Palace BBS (1:3642/506) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 23:03 From: Michael Diresta To: Andrew Sempere Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Hi, If you get the plans I'd like a copy. I built one years ago and it not longer works and naturally I lost the plans. I love to see if I could get it running again. ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 23:46 From: Andrew Sempere To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RJT>> Popular Electronics. One was about 3 or 4 feet tall, RJT>> and would generate anywhere from 250,000-750,000 volts RJT>> depending on how many glass-plate capacitors... RJT> Great! Sorry I can't be more specific about what RJT> issue it was in, or even the year. I'd say that the RJT> odds are pretty good that it was 1965 or earlier, if RJT> I had to take a guess. Yeah, if you get this let me Well, I checked one database, and the only entry they had was for Radio Electronics, Sept '91, p33: "plans for construction of a solid state Tesla coil" The issue was checked out so I didn't get a chance to look at it, although I don't think this is the same artical you are talking about... I'll keep looking and keep you posted... -Andrew ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-07-94 21:59 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> The tower of the Wardenclyffe commercial plant built in 1901 RQ> was 167 feet tall (air terminal) on a stone and concrete RQ> foundation that exended 50 feet below the water table (the RQ> ground terminal). AS> Wow :) Sounds like a very large, very expensive project. Yes. AS> Incidentally, was it ever operational? Briefly at reduced powers. The transmitter had it's own power plant and shop. Tesla remarked in foreclosure hearings and depositions relating to this work on the coal expense at Wardenclyff. During depositions, he submitted photos of multi- phase high speed generators weighing several tons... "Reduced power" on the Wardenclyff machine would be around 250 KVA guesstimate. Note that this is not the Colorado Springs machine which processed around 250 KVA when maXed. AS> ... (the coil) caused all the corn fields within a 20 mile AS> radius to spontaneously combust :) -Andrew RQ> Nothing like this ever occured... AS> Too Bad... I heard the story at an electricity demonstration Not that I am aware of anyway. There are some pretty wild "eyewitness" reports of effects. Most people don't pay attention to the solid evidence such as photographs, notes, court hearings, etc., that document the size and power levels of his equipment. The facts are so commonly distorted that what is popularized is almost as damaging as what was left unsaid. Tesla is the father of an entire age of man's history. Long before lightning at Colorado Springs, Tesla had designed and patented key aspects of the nations 60 cycle power grid. His work with higher frequency electricity led him to key patents in Radio, confirmed by the US Supreme Court in 1943. His list of related diagrams and patents for mechanical, electro-mechanical and electrical equipment leaves little to the imagination when taken as a whole. His work was revolutionary. Long before Marconi could send a "click" across the English Channel; Tesla had equipment that was capable of sending and receiving signals hundereds, if not thousands, of miles. As the inventor of the first commercial alternating current power system at Niagra Falls, now in use worldwide, he was quite familiar with industrial scale operations. His work with the experimental oscillator at Colorado Springs, and later the unfinished (but operational) commerical plant on Long Island (Wardenclyff), were his efforts to globally supply both information and energy without wires. These plants required conventional (hydro, steam) power supplies. No energy was "created" or "free". In the Wardenclyff plant, the coal bill for operations was a stress on Tesla's finances, and the plant later went into forclosure. The major components of these systems were simple: Ground, primary coil, secondary or "driver" coil, extra coil, air terminal, and power supply components to drive the primary coil; such as high voltage pulse discharging capacitors, step up xfmrs, and primary spark gap or break device. The principal of operation would take another post of this length to cover in any detail, but suffice now to say that the ground and air terminal currents were very very large. Side effects from operation of the coil system at Colorado Springs were noted by Tesla as well as others, and were frequently repeated. These effects included; people reported drawing electrical arcs (not static electricty) from water pipes to their bodies throughout the town of Colorado Springs, insects took flight covered in St. Elmo's Fire, horses were pulling electrical arcs (not static electricity) from the ground to their shoes, local atmospheric illumination (corona type effects) around the machine, etc.. Like I said, too much has been sensationalized, but the true facts really strike home. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-03-94 17:52 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ You were posting this to Blair Groves, but I finally succumbed.. AS> (hence the burning of fossil fuels that destroy the ozone AS> layer) From what I have read it is chloroflorocarbons that have been firmly identified as responsible for atmospheric ozone depletion, products such as "freon" used in the chillers of air conditioning systems and propelents in spray cans. AS> I heard that Tesla himself build a 10 story coil that was AS> capable of lighting up bulbs 20 miles away.... The tower of the Wardenclyffe commercial plant built in 1901 was 167 feet tall (air terminal) on a stone and concrete foundation that exended 50 feet below the water table (the ground terminal). The power station built near the tower had footings poured for four massive multi-phase generators to drive what at the time was the largest capacitor bank in the world. The coil was steam powered, with one boiler and generator operational. AS> ... (the coil) caused all the corn fields within a 20 mile AS> radius to spontaneously combust :) -Andrew Nothing like this ever occured, though many of the effects of his oscillators were even stranger. He experimented with mechanical, and electromechanical, oscillators in addition to the purely electrical devices such as the Tesla coil. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-05-94 00:24 From: Andrew Sempere To: Richard Quick Subj: 10KVA TESLA COIL ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ * Original From: Norman Cardillo (1:324/114) * Original To : Andrew Sempere (1:324/114) Somebody once said that power should be transmitted with Tesla Coils instead of using wires, because those wires running every- where cause a health problem. This would probably cause more problems than transmission lines. ! Origin: AEOLUS - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-06-94 18:25 From: Richard Quick To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Bob Patten to All <=- BP> I'm interested in building a Tesla coil using a ham BP> transmitter as the power source (if it's possible). There are at least two ways that I can think of to run a coil from a driver such as this. But I would not advise doing it. The ham equipment, powerful as it is, is not designed to drive a coil to spark. You would be better (and it would be much safer for the HAM xmittr) to design a tube driven or spark gap excited tank circuit to drive a coil. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-07-94 01:22 From: Bob Patten To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> BP> I'm interested in building a Tesla coil using a ham -> BP> transmitter power source (if it's possible). -> -> Why would you want to do that? Because it's there! (The Kenwood TS-430S on my desk). I have an RF source, I don't have a neon sign xfmr, etc. For economy, out of curiosity, etc. ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-07-94 18:07 From: James Meyer To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ On 06-05-94, ROY J. TELLASON wrote to BOB PATTEN and said: RJ> BP> building a Tesla coil using a ham transmitter as the RJ> BP> power source (if it's possible). RJ> RJ> Why would you want to do that? Efficiency, Roy. That and the fact that it would be much easier to only have to wind and tune the high voltage secondary. You don't have to mess around with neon sign transformers and spark gaps. If Tesla were alive and experimenting today, he wouldn't still be using spark gaps to produce his RF to drive his coils with. Jim ! Origin: (Durham, NC) 919-286-4542 (1:3641/224) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 07:07 From: Dave Mcknight To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> Nothing like this ever occured, though many of the effects RQ> of his oscillators were even stranger. He experimented with RQ> mechanical, and electromechanical, oscillators in addition RQ> to the purely electrical devices such as the Tesla coil. Although this might be off topic, could you post a brief explanation of the mechanical and electromechanical oscillators Tesla experimented with? I've read a number of books on his coils, but this is the first I've heard of this. ! Origin: (614)861-8377 (1:226/110) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 01:18 From: Bob Patten To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> There are at least two ways that I can think of to run a coil -> from a driver such as this. But I would not advise doing it. -> The ham equipment, powerful as it is, is not designed to drive -> a coil to spark. -> You would be better (and it would be much safer for the HAM -> xmittr) to design a tube driven or spark gap excited tank -> circuit to drive a coil. The KW amplifier is tube drive, but lowest frequency it works on is 3.5Mhz. So what are the two ways that you can think of? I'm just trying to collect all the possibilities before I decide how to go. I may end up shopping for a neon sign xfmr and building the conventional design... ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 20:37 From: Michael Diresta To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Thanks Richard, That info should keep me busy for some time. I'll let you know how I make out. (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-09-94 18:03 From: Andrew Sempere To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> "Reduced power" on the Wardenclyff machine would be around RQ> 250 KVA guesstimate. Note that this is not the Colorado RQ> Springs machine which processed around 250 KVA when maXed. RQ> ... Colorado Springs, insects took flight covered in RQ> St. Elmo's Fire, horses were pulling electrical arcs (not RQ> static electricity) from the ground to their shoes, local RQ> atmospheric illumination (corona type effects) around the RQ> machine, etc.. Really very interesting... I think I might do some research on Tesla myself, sounds quite fascinating. Do any of Tesla's plants (besides Niagra) still exist? What about the Wardenclyff plant? -Andrew - Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 03:46 From: Greg Purvis To: Norman Cardillo Subj: TESLA COIL, But Power & O ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ NC> Somebody once said that power should be transmitted with NC> Tesla Coils instead of using wires, because those wires NC> running everywhere cause a health problem. I read an article in the New Yorker some years back which I tore out and kept, about some people who were hunting down evidence that powerline EMF's were causing their own honorable amount of havoc with white cells, fetal gestation, and other problems within the systems of people who lived close to HTWires and transformers, and so on. I've since seen other references (and I DON'T have copies, unfortunately) to one or more people mentioned in this first article which refutes either the motives of these people or the conclusions that they've come to. The New Yorker article is several pages each over three issues, so if you are interested in reading it, please let me know where I can send photocopys. I'm afraid it's too much to scan and have our NEC's travel along on their dime. I can't and don't dwell on this subject about how the raw bi- product(s) of electricity may harm people. Who can? Still, if within my lifetime and my financial means there is a way to identify problems and compensate for those problems, I'd like to know of them, and how I may be able to take part in a 'cleaner electrical future'. I need information too, so just leave a note to me if you want copies of this article and you've got it. I look forward to more discussion on this topic. ... Three types of lies: lies, damn lies, and statistics - Mark Twain Pembroke Ont. CAN. 613-735-5170 (1:241/12) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 19:44 From: Andrew Sempere To: Randy Dixon Subj: Tesla coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RD> I knew a Guy whom made one and lit up a guy 2 houses RD> down whom was using his telephone, so please be careful RD> when testing these toys... Randy Hmmmm... I can think of a few people I'd like to light up :) Just kidding, thanks for the warning, I'll keep it in mind when it comes time to flip the switch.. Andrew (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 20:54 From: Richard Quick To: Dave Mcknight Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Dave Mcknight to Richard Quick <=- DM> Although this might be off topic, could you post a brief DM> explanation of the mechanical and electromechanical DM> oscillators Tesla experimented with? I've read a number of DM> books on his coils, but this is the first I've heard of DM> this. OK, Real brief... Tesla invented some very accurate mechanical and electro- mechanical oscillators. Several of these were patented. These oscillators were steam or compressed air fired. The electromechanical oscillators were made to produce a frequency stable alternating current by mounting a coil around a mechanically oscillating armature. Tesla also held patents on high speed, high frequency alternators. By using the frequency stable output from a steam fired electromechanical oscillator to excite the field windings on the high speed alternator, a high power, frequency stable, CW RF current was produced. This is radio. Tesla continued to develop the circuit for power and efficiency and included many variations and modifications in his patent applications covering all aspects of his grounded tuned circuit (multiplexing, receiver circuits, power supplies, etc) 1890-1893 The radio circuits are not that obvious until you look at the steam fired generator sets that were used power them. The RF alternators were weighing several hundreds of pounds by 1893; they were steam engine driven (later turbine), ran up to 20,000 RPM, and produced 8 KVA (plus) of RF signal. The field coils on the high speed alternator could be excited by frequency stable AC signal from an electromechanical oscillator (these were running 10+ horsepower in 1893) and the steam pressure was closely regulated. The signal from the antenna was very stable CW. The high speed alternators were patented under the description "System for Arc Lighting", and indeed, he did sell a generator set to the city if New York for powering several blocks of his arc lamps. Run unregulated, they could be used to make killer light shows, run with speed regulation they made excellent CW RF power supplies. By this time he was also patenting vacuum sealed oil capacitors, high speed mechanical breaks (sparkgaps), air core (coil) transformers, to name a few. The Complete Patents shows the parallel development in these areas; both the complexity of the circuits, and the power of the steam driven alternators and electromechanical oscillators. I should note here that many patents were issued years after they were submitted (and many years after their invention), and many many more ideas and techniques went unpatented. Photos, sketches, and the related patent numbers and dates of much of this equipment is discussed by Tesla in his depositions to his attorneys, and these depositions are published as: Nickola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power. Note this work was all done after he patented a motor based on a rotating magnetic field (AC induction motor) and other key elements of our "modern" power grid, and that this was before his high powered resonator work at Colorado Springs and Wardenclyff. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 22:43 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ AS> Do any of Tesla's plants (besides Niagra) still exist? What AS> about the Wardenclyff plant? -Andrew Not to my knowledge, all the later stuff... gone. Wardenclyff was broken into by vandals who smashed Tesla's lifetime accumulation of tubes, xfmrs, radios, robot projects, etc.. The thieves stole for scrap what they could not smash; all the boiler brass, copper motor/generator windings, etc.. were stripped. Witnesses stated that after one particularly bad week of vandalism all the windows had been smashed, office furnature lay broken outside in the rain, and pages of Tesla's hand written notes were blowing in the wind. At this point Tesla was close to destitute and could not afford a caretaker at the uncompleted plant. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 22:25 From: Richard Quick To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> There are at least two ways that I can think of to run a coil -> from a driver such as this. But I would not advise doing it. -> The ham equipment, powerful as it is, is not designed to -> drive a coil to spark. BP> The KW amplifier is tube drive, but lowest frequency it BP> works on is 3.5Mhz. Tube coils work best around 450 kHz or less. Your output will be more corona than lightning at 3.5 mHz; excellent for lighting up vacuum tubes and what not, but not a good sparker. BP> So what are the two ways that you can think of? I'm just BP> trying to collect all the possibilities before I decide how BP> to go. I may end up shopping for a neon sign xfmr and BP> building the conventional design... The first way is to wind ~3.5 mHz coil, then carefully match the frequency output of the transmitter to the frequency of the coil, (they must be within a few kHz). When both xmitr and coil are at the same frequency, the output of the xmitr may be run directly into the coil base wire. This is a base fed secondary coil driven by an RF current. Problems include impedance matching, and frequency drift. The second way is to inductively couple a coil set. A primary coil is made up of 5-8 turns of heavy conductor. One end of the primary coil is grounded with the xmitr housing, the other end is fed the xmitr output. The 3.5 mHz coil is set inside (or placed in close proximity to) the heavy primary coil, and the base wire of the secondary is grounded as well. The coil will be excited by induction from the energized primary. Problems include low efficiency (due to low coupling coefficients, and low peak powers), and difficulties in frequency matching the two circuits. Depending on the nature of the experiments to be performed, each method has it's advantages and disadvantages. You would probably end up switching back and forth between these two. The driver (radio transmitter in this instance) will not give any real goose to a Tesla coil (which is simply a 1/4 wave resonator). In practice tube coilers tend to operate at much lower frequencies with a Class C type amplifier, where additional power tubes may be ganged up for more KVA. But all of these CW (Continuous Wave) circuits are peak power limited: In other words your peak coil discharges are not much greater than the rms ratings of your power tube(s). When you go to spark gap excited tank circuits you lose most of your CW (unless your are a real spark gap engineer) but your peak powers climb through the proverbial roof. Even a cheapy, home built in three hours, salt water capacitor will give you a much greater peak power than your 3 KVA xmitr run flat out. A cheapy salt water cap is much less expensive to replace or simply scrap than a quality power tube(s). If you are really serious about tube coils, use the proper frequency range class C amplifier circuit. VACUUM TUBE INDUSTRIES, INC., 506 North Warren Ave., P.O. Box 2009, Brocton, Massachusetts, 02405-2009, specializes in 450 kHz power tubes for use in commercial RF induction heaters. They carry a full line of filament xfrmrs and HV plate xfmrs, cooling jackets, power controllers etc.. These are the ideal type tubes for Tesla Coils that are driven by Class C amplifiers. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 23:21 From: Richard Quick To: Randy Dixon Subj: Tesla coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Randy Dixon <=- RD> I knew a Guy whom made one and lit up a guy 2 houses RD> down whom was using his telephone, so please be careful RD> when testing these toys... Randy The biggest thing missed for safe coil operation is a heavy, dedicated, RF ground that is completely electrically isolated from all other ground points. If you have a ground loop problem (Tesla Coil), and your ground is the same as Ma Bell is using, then you can expect some complaints/problems. Tesla coil experiments require that the system ground have enormous surface area in contact with moist earth. All ground connections must be short, direct, and traversed with large surface area conductors such as strap, heavy coax shield, copper pipe, aluminum strips etc.. Don't ground to the water pipe! Don't ground your coil to your breaker box! Avoid: telephone, cable TV, antenna or power utility grounds, and gas pipes. Don't ground to conductors that stick up in the air: gutters, downspouts, fences, etc.. Do sink pipes and rods into the ground. Bury wire screen mats. Throw aluminum flashing into a water filled ditch, well, stream, pond, or lake. Connect iron or galvinized sewer pipe and culverts. Grounds should be kept wet. All connections should be short with lots of surface area. I like a bunch of 8' copper pipes driven into small depressions around a back yard: soldered connections, 1/2" ground strap, central connection made no more than 20 feet from the base of the coil. Another favorite: buried hydraulic car lift lacking a direct metal connection to the compressor. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 07:07 From: Dave Mcknight To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> Nothing like this ever occured, though many of the effects RQ> of his oscillators were even stranger. He experimented with RQ> mechanical, and electromechanical, oscillators in addition RQ> to the purely electrical devices such as the Tesla coil. Although this might be off topic, could you post a brief explanation of the mechanical and electromechanical oscillators Tesla experimented with? I've read a number of books on his coils, but this is the first I've heard of this. OH (614)861-8377 (1:226/110) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 20:54 From: Richard Quick To: Dave Mcknight Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Dave Mcknight to Richard Quick <=- DM> Although this might be off topic, could you post a brief DM> explanation of the mechanical and electromechanical DM> oscillators Tesla experimented with? I've read a number of DM> books on his coils, but this is the first I've heard of DM> this. OK, Real brief... Tesla invented some very accurate mechanical and electro- mechanical oscillators. Several of these were patented. These oscillators were steam or compressed air fired. The electromechanical oscillators were made to produce a frequency stable alternating current by mounting a coil around a mechanically oscillating armature. Tesla also held patents on high speed, high frequency alternators. By using the frequency stable output from a steam fired electromechanical oscillator to excite the field windings on the high speed alternator, a high power, frequency stable, CW RF current was produced. This is radio. Tesla continued to develop the circuit for power and efficiency and included many variations and modifications in his patent applications covering all aspects of his grounded tuned circuit (multiplexing, receiver circuits, power supplies, etc) 1890-1893 The radio circuits are not that obvious until you look at the steam fired generator sets that were used power them. The RF alternators were weighing several hundreds of pounds by 1893; they were steam engine driven (later turbine), ran up to 20,000 RPM, and produced 8 KVA (plus) of RF signal. The field coils on the high speed alternator could be excited by frequency stable AC signal from an electromechanical oscillator (these were running 10+ horsepower in 1893) and the steam pressure was closely regulated. The signal from the antenna was very stable CW. The high speed alternators were patented under the description "System for Arc Lighting", and indeed, he did sell a generator set to the city if New York for powering several blocks of his arc lamps. Run unregulated, they could be used to make killer light shows, run with speed regulation they made excellent CW RF power supplies. By this time he was also patenting vacuum sealed oil capacitors, high speed mechanical breaks (sparkgaps), air core (coil) transformers, to name a few. The Complete Patents shows the parallel development in these areas; both the complexity of the circuits, and the power of the steam driven alternators and electromechanical oscillators. I should note here that many patents were issued years after they were submitted (and many years after their invention), and many many more ideas and techniques went unpatented. Photos, sketches, and the related patent numbers and dates of much of this equipment is discussed by Tesla in his depositions to his attorneys, and these depositions are published as: Nickola Tesla On His Work With Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power. Note this work was all done after he patented a motor based on a rotating magnetic field (AC induction motor) and other key elements of our "modern" power grid, and that this was before his high powered resonator work at Colorado Springs and Wardenclyff. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-10-94 22:43 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ AS> Do any of Tesla's plants (besides Niagra) still exist? What AS> about the Wardenclyff plant? -Andrew Not to my knowledge, all the later stuff... gone. Wardenclyff was broken into by vandals who smashed Tesla's lifetime accumulation of tubes, xfmrs, radios, robot projects, etc.. The thieves stole for scrap what they could not smash; all the boiler brass, copper motor/generator windings, etc.. were stripped. Witnesses stated that after one particularly bad week of vandalism all the windows had been smashed, office furnature lay broken outside in the rain, and pages of Tesla's hand written notes were blowing in the wind. At this point Tesla was close to destitute and could not afford a caretaker at the uncompleted plant. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-08-94 19:00 From: Don Kimberlin To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS>You could quite easily turn a Tesla coil into a transmitter, TS>generating sign types not approved for HAM use, at strengths TS>well above Part 15 limits. Below 9 kHz such limits would not TS>apply. TS>Other than by only operating it well inside the boundaries of TS>a BIG piece of private property, I wonder what kind of induced TS>and radiated signal strenght are produced by large Tesla TS>coils. I'd guess that what sounds like a 50 KVA unit TS>discussed here probably substantially exceeds Part 15 TS>unintentional radiator emmissions limits. TS>If Richard, or the others playing with toys, notice... Over TS>what range of frequencies are you guys producing emmissions, TS>and at what kind of field/distance? I'd imagine some coils TS>produce an unstable (in terms of frequency) output over a 10 TS>or 100 to 1 range, while others may be stable within 5% or TS>less. Is this a reasonable presumption? TS>Have any of these coils been monitored with field strength TS>meters, or spectrum analyzers with calibrated antenna sets? ...I hate to raise that ominous spectre, but I've heard a couple of non-tech blurbs over the past year or so about such matters. One was a chap somewhere around San Francisco who got hold of an old Federal enclosed arc generator (Federal made U.S. versions of the Danish Poulsen arc, the largest of which was a megawatt, placed in the WWI US Navy sparker at Bordeaux, France as a back-up in case the Germans cut the transatlantic telegraph cables to the U.S.), and another story - might have been the same person - purchased the RCA Marconi-made 300 kW sparkers from Bolinas, CA (just north of SFO) for junk prices. Seems the government people got right on his case, cited "safety reasons" more than RFI. Seems like that stuff generates spurs clear up beyond daylight, at least so the government was supposed to be claiming...not a nice thought, if one has the Feds on their tail...kind of like a "forbidden fruit" of electronics, mayhaps? Concord,N.C. (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-11-94 00:14 From: Terry Smith To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> The tower of the Wardenclyffe commercial plant built in 1901 RQ> was 167 feet tall (air terminal) on a stone and concrete RQ> "Reduced power" on the Wardenclyff machine would be around RQ> 250 KVA guesstimate. Note that this is not the Colorado RQ> Springs Trying to do some projections, was this system designed to operate at around 15-20 megavolts, with around 15-40 mA current being sustained? Is your 10 KVA coil discussed here operated around 2 MV, 5 mA ? That "little one" almost sounds safe to play with! Terry ps: On thinking about FCC considerations, it's pretty likely that these Tesla coils are highly in violation of today's rules and regs. Even some of the little units used in labs to ignite gas mixes probably exceed Part 15 limits. What are the frequency extremes you've used for various coils? Do you think a Tesla coil could be built in such a manner as to confine primary emmissions to 6.78 MHz +/-15 KHz? This is the lowest frequency of the ISM band (FCC Part 18), in which power and signal emmissions in band are unlimited. The 2nd and 4th harmonics of 6.78 MHz are also ISM, and therefore unrestricted. Out of band signals would have to be less than 10 uV/m at 1600 M to be legal on such frequencies, or if operated outside ISM bands at substantially over 500 watts. I suspect this means that to be legal, any large Tesla coils would have to be built outside the US. I presume you are operating well below the lowest ISM frequency and emit signals that would create more than a barely audible crackle on a radio with an AM detector 100 feet away? (The latter being a rough translation of 10 uV/m @ 1600 M to .5 mV/m @ 100') ! Origin: Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-12-94 14:59 From: Andrew Sempere To: Bob Patten Subj: Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Thanks for the tesla coil plans! I got them on Wednesday (Sorry about the extra stamp) Thanks also for the section on Kirlian photography, I'll let you know how it all turns out... -Andrew Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-12-94 08:28 From: Richard Quick To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DK> ...I hate to raise that ominous spectre... DK> old Federal enclosed arc generator (Federal made U.S. DK> versions of the Danish Poulsen arc, the largest of which was DK> a megawatt, and DK> person - purchased the RCA Marconi-made 300 kW sparkers from DK> Bolinas, CA (just north of SFO) for junk prices. Seems the DK> government people got right on his case, cited "safety DK> reasons" But it must also be understood that both the HF generator and the Marconi coil were designed specificlly to transmit RF. These designs aimed for power, (at the time thought essential for long distance xmission), and not so much for a stable frequency. I have photocopies of pictures taken of the Marconi coils. No way could a clean signal be produced by this work. And there IS the "safety problem"; the spark gaps, boilers, generator sets, etc., should be considered hazardous. I know that in Illinois where they have steam tractor meets, all steam boilers must be inspected and licensed by the state. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-13-94 22:29 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> "Reduced power" on the Wardenclyff machine would be around RQ> 250 KVA guesstimate. TS> Trying to do some projections, was this system designed to TS> operate at around 15-20 megavolts, with around 15-40 mA TS> current being sustained? Boy are you ever in the stone age on this subject. 15 - 40 mA???? Tesla's peak power ran over a gigawatt. (work it backwards...) TS> Is your 10 KVA coil discussed here operated around 2 MV, 5 TS> mA ? My 10" coil has a peak power of over 2 megawatts. TS> That "little one" almost sounds safe to play with! yea right..., and you are almost an order of magnitude out of the ballpark with your deductions. You clearly show that you have not even looked up or attempted to understand a simple spark excited tank circuit. Much less a resonate transformer. Now you proceed to go off about the legal ramifications of a circuit you do not understand. TS> ps: On thinking about FCC considerations, TS> it's pretty likely that these Tesla coils are highly in TS> violation of today's rules and regs. It's even more likely you don't have a clue... TS> Even some of the little units used in labs to ignite gas TS> mixes probably exceed Part 15 limits. Are you paid to do this with your time or do you volunteer? Do you have a job? TS> What are the frequency extremes you've used for various TS> coils? I would have to open up my lab journal, but I can tell you what FIDO extremes I have seen. TS> Do you think a Tesla coil could be built in such a manner as TS> to confine primary emmissions to 6.78 MHz +/-15 KHz? Sure, why don't you spend a minute and sketch a circuit diagram and design a resonator for this. TS> This is the lowest frequency of the ISM band (FCC Part 18), TS> in which power and signal emmissions in band are unlimited. TS> The 2nd and 4th harmonics of 6.78 MHz are also ISM, and TS> therefore unrestricted. Humm, I know you are unrestricted. Frequency Extremes... TS> Out of band signals would have to be less than 10 uV/m at TS> 1600 M to be legal on such frequencies, or if operated TS> outside ISM bands at substantially over 500 watts. Oh, yes I am sure this applies.... TS> I suspect this means that to be legal, any large Tesla coils TS> would have to be built outside the US. Boy you suspect me too... even after I posted my name and address to the whole world.... TS> I presume you are operating well below the lowest ISM TS> frequency and emit signals that would create more TS> than a barely audible crackle on a radio with an AM detector TS> 100 feet away? (The latter being a rough translation of 10 TS> uV/m @ 1600 M to .5> mV/m @ 100') From the very beginning of your post to me you have been very much incorrect in your projections, assumptions, and suspicions. You would waste a lot of my valuable time defending a legal, educational, and entertaining field of discussion and experi- mentaion. Properly built and operated, Tesla coils are not the nightmare interference you are. ... If all else fails... Throw another Megavolt across it! ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-13-94 23:07 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS> ps: On thinking about FCC considerations, it's pretty TS> likely that these Tesla coils are highly in violation of TS> today's rules and regs. TS> ! Origin: Charges filed under Ohms Law! (203)732-0575 BBS ps: You are twice now accusing me of being in "violation" of something you appear to know nothing (Tesla Coils) about??? My neighbors nextdoor don't have problem, why do you??? If it means anything to you, this work has been going on since Faraday first discharged a capacitor. Now Terry, you and I have discussed capacitors for these projects, and I can honestly say I appreciated your input, but for some reason you act now like you fell out a tree. Or, could that have been another Terry Smith? I seem to recall a lot of Terry Smith's out here getting their messages crossed up... Showing up in their personal mailboxes etc.. I don't know. I have been on a year and have never had a problem with Terry Smith before, seemed like a resonable guy, offered up a couple of prospective capacitor types for Tesla projects. Well regardless: practical circuit assistance, capacitor (or coil) designs, or construction plans, spark gap ideas, grounding techniques, references, etc. are always welcome and appreciated. Thank You ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-13-94 08:29 From: Tom Moeller To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Bob Patten wrote in a message to Terry Smith: -> BP> I'm interested in building a Tesla coil using a ham -> BP> transmitter power source (if it's possible). BP> Well, in my case, I could always key it and make some CW BP> QSO's whilst demonstrating the effects of the Tesla coil. I BP> imagine it would radiate a clean CW signal... Yeah, on visual as well as RF! |-} and no messy lamp filaments to burn out either. Tom ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-14-94 08:22 From: Bob Patten To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> If you are really serious about tube coils, use the proper -> frequency range class C amplifier circuit. -> VACUUM TUBE INDUSTRIES, INC., 506 North Warren Ave., P.O. Box -> 2009, Brocton, Massachusetts, 02405-2009, specializes in 450 -> kHz power tubes for use in commercial RF induction heaters. -> They carry a full line of filament xfrmrs and HV plate xfmrs, -> cooling jackets, power controllers etc.. These are the ideal - > type tubes for Tesla Coils that are driven by Class C -> amplifiers. Thanks for all the info Richard. I did a hard copy of the full message and will study it for ideas. I also requested info on publications about tube coils from the Tesla Society in Colorado Springs that I read about in someone else's message here... ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-15-94 02:16 From: Bob Patten To: Tom Moeller Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BP> I'm interested in building a Tesla coil using a ham transmitt BP> power source (if it's possible). BP> Well, in my case, I could always key it and make some CW BP> QSO's whilst demonstrating the effects of the Tesla coil. BP> I imagine it would radiate a clean CW signal... -> Yeah, on visual as well as RF! |-} and no messy lamp filaments -> to burn out either. What gave me the idea was the memory of running a KW to a short top loaded vertical on 3.5Mhz. On a humid night, it would shoot out a horiz spark about a foot long... (305) 472-7715 28800 V.32bis (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-16-94 00:10 From: Andrew Sempere To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> broken into by vandals who smashed Tesla's lifetime RQ> accumulation of tubes, xfmrs, radios, robot projects, etc.. RQ> The thieves stole for scrap what they could not smash; all RQ> the boiler brass, copper motor/generator windings, etc.. RQ> were stripped. Witnesses stated that after one particularly RQ> bad week of vandalism all the windows had been smashed, RQ> office furnature lay broken outside in the rain, and pages RQ> of Tesla's hand written notes were blowing in the wind. At RQ> this point Tesla was close to destitute and could not RQ> afford a caretaker at the uncompleted plant. That sucks! What a waste... When did Tesla die? Andover, MA, USA - (508) 474-0328 (1:324/114) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-15-94 17:39 From: Jamar Neal To: Richard Quick Subj: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Were did Tesla fit into the battle for the electricity market between Edison and Westinghouse? This was about the right time period right? Jamar 314-339-0248 (1:287/516) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-14-94 22:39 From: Don Kimberlin To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> DK> ...I hate to raise that ominous spectre... RQ> DK> old Federal enclosed arc generator (Federal made U.S. RQ> DK> versions of the Danish Poulsen arc, the largest of which RQ> DK> was a megawatt, RQ>and RQ> DK> person - purchased the RCA Marconi-made 300 kW sparkers RQ> DK> from Bolinas, CA (just north of SFO) for junk prices. RQ> DK> Seems the government people got right on his case, cited RQ> DK> "safety reasons" RQ>But it must also be understood that both the HF generator and RQ>the Marconi coil were designed specificlly to transmit RF. RQ> These designs aimed for power, (at the time thought essential RQ>for long distance xmission), and not so much for a stable RQ>frequency. RQ>I have photocopies of pictures taken of the Marconi coils. No RQ>way could a clean signal be produced by this work. And there RQ>IS the "safety problem"; the spark gaps, boilers, generator RQ>sets, etc., should be considered hazardous. I know that in RQ>Illinois where they have steam tractor meets, all steam RQ>boilers must be inspected and licensed by the state. ...all the more important then, in the case of those who would build Tesla coils today, that they understand how to make really high-efficiency ones, then, eh? I know an awful lot of the Pop-Tronics "projects" of the old magazines resulted in awfully sloppy things that thrilled people with six inches or a foot of discharge, which worked out to a horrible inefficiency for the input they were running.... Concord,N.C. (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-16-94 23:36 From: Sjoerd Schaafsma To: Richard Quick Subj: Re: Tesla Coils, Video ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Howdy Richard: RQ> If you have any problems, questions, comments, corrections, RQ> etc., please post me. Since your tape was sent out of the RQ> country I would appreciate it if you would let me know when RQ> it arrives. Thanks a bunch Richard, I'll let you know as soon as it arrives. I hope the MO I sent was enough to cover your postage, I have little idea what it is, but it usually is less than the comparable service in Canada. I'm looking forward to seeing the sparks fly! ... Sjoerd Schaafsma - An occasional 8 bit holdout [403]327-9731 Lethbridge,AB (1:358/17) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 6-16-94 20:45 From: Richard Quick To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> If you are really serious about tube coils, use the proper -> frequency range class C amplifier circuit. RQ BP> Thanks for all the info Richard. I did a hard copy of the BP> full message and will study it for ideas. Your very welcome. I hope I was of some help. BP> I also requested info on publications about tube coils from BP> the Tesla Society in Colorado Springs that I read about in BP> someone else's message here... There is an excellent article in the latest issue of the Tesla Coil Builders Association (TCBA) publication, "NEWS" (vol. 13, #3 Jul,Aug,Sep,'94) on high powered coiling (36" spark lengths running three #833 power tubes, 8+ KVA). The previous issue ran an article on a 5.2 mHz, pulse generator driven, coil. ............................................................ > Retrieved from archives. > Date: 06-15-94 02:16 > From: Bob Patten > To: Tom Moeller > Subj: Tesla Coils BP>What gave me the idea was the memory of running a KW to a BP>short top loaded vertical on 3.5Mhz. On a humid night, it BP> would shoot out a horiz spark about a foot long... ............................................................. Yeah, this is base feeding a 1/4 wave resonator with a high current signal, a-la Colorado Springs. High Q resonators can produce some pretty decent voltage rises, as witnessed by the spark discharge and corona. Your efficiency in the resonator had to be good, with a nice frequency and impedance match. A Tesla coil normally operates at a lower frequency to transform high power. Larger capacitors increase power, but reduce the tank circuit frequency. To compensate for the reduced frequency in the oscillator (Tesla Tank) circuit; the resonator (Tesla Coil) frequency must also be reduced. This maintains a match or "tune". The most common practice used in maintaining the tune of the 1/4 wave (voltage producing) resonator (coil) is to increase the conductor length, and/or, top load the coil with some type capacitive discharger. In tube (CW) coils; larger dischargers (conductive spheres, toroids, etc.) are not satisfactory sparkers unless some pointed surface is provided for breakout. Adding wire length to the resonator for frequency reduction seems to work best for tube type or CW coils. But then a problem arises... The impedance increases rapidly with the use of longer cond- uctors. To get around this, larger, lower resistance conductors must be wound on fatter coil forms. This goes a long way towards maintaining the efficiency or "Q" of the Tesla Coil, or properly the " 1/4 slow-wave helical resonator". By the way, using tube amplifier circuits it is possible to drive higher frequency resonators with good power. The resonator geometries at these higher frequencies must change to reach higher Qs. As the coil's efficiency drops way off as frequency goes up. A good example of a resonate structure at higher frequency is the typical tube driven cavity resonator kitchen utensil, the microwave oven. Some examples of resonate structures include: the tube driven Sloan X-Ray machine (1935, coaxial helical resonator), the pure RF cavity resonator Hanson documented 1938, and the Phermex 50 mHz cavity accelerator. In addition there have been several Russian attempts at RF cavity resonate fusion machines. Tesla determined that the earth is an electrically resonate structure (cavity) in what is now know as the Shumann Cavity. This was all started with Tesla's resonate coils. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-17-94 20:26 From: Richard Quick To: Andrew Sempere Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ AS> When did Tesla die? 10:30 P.M on January 7,1943 in his New York hotel room. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-17-94 18:01 From: Richard Quick To: Jamar Neal Subj: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Jamar Neal to Richard Quick <=- JN> Were did Tesla fit into the battle for the electricity JN> market between Edison and Westinghouse? This was about the JN> right time period right? Edison had already established a lab here in the US before Tesla arrived in New York from Europe. Edison was proposing that DC power be used for residential lighting and industry. Tesla worked for some months in Edison's lab, and a definite difference of opinion developed. Tesla left disgusted. Tesla realized that DC was essential in certain industrial applications, such as producing aluminum; but for most other purposes, alternating currents (AC) worked as well as DC, and frequently AC worked much better. Tesla held patents for motors and alternators based on his system of AC power production, step up transformation, transmission, step down transformation, and utilization. His motor operated without carbon brushes, running instead on his patented rotating magnetic field. It always turned the same direction regardless of which way the plug was wired. Edison's system of DC power production and transmission was very inefficient. The amount of copper involved was amazing. Two blocks from a dynamo station the DC voltage was very high, but 10 blocks away people complained about dim lights and fires from overheated conductors. Lighting New York City was going to require at least 5 DC steam powerplants in the center of the city, one in each major section. The coal pollution was already dense, and steam boiler explosions were becoming both worse and more frequent as more and larger boilers were operated at higher pressure. Tesla offered a way to produce electricity at a remote site and then conduct the power to the population centers. Tesla was not able to get a construction contract with his system in the United States, but he was awarded a contract in Canada. He delivered sketches and specifications to Westinghouse for a system to generate hydroelectric power from the Niagara river for the commercial production of aluminum 20 miles away. The high voltage transmission was very economical. It appears that Tesla agreed to a one-time payment of one million dollars, and the 60 cycle patents remained with Westinghouse. The money was spent in the lab developing his next generation projects. Tesla's system was universally adopted in one country after another, yet Edison gets credit for lighting the world. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-17-94 20:17 From: Richard Quick To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DK> ...all the more important then, in the case of those who DK> would build Tesla coils today, that they understand how to DK> make really high-efficiency ones, then, eh? I know an awful DK> lot of the Pop-Tronics "projects" of the old magazines DK> resulted in awfully sloppy things that thrilled people with DK> six inches or a foot of discharge, which worked out to a DK> horrible inefficiency for the input they were running.... The goal should always be maximum efficiency. This is the major reason that Tesla himself left two coil systems behind, and developed the three coil system (primary, secondary, extra coil) to industrial scale. But even some experienced coilers need to learn the "rules of the road" when it comes to simple coils. A heavy, dedicated, RF ground is a must for any serious coiling. Experiments should then seek to convert every possible watt into spark, where the energy is consumed as heat, light, sound, etc.. The coil base wire is the source of most of the spurious signal. The output here is a low voltage RF current at quite a few rms amps. The signal seems to conduct better than it radiates, so just make sure your ground path is equipped for it. Remember too that spark gap Tesla Coils are disruptive. The output from coils excited by spark gap tank circuits does not radiate well, and is a far cry from CW. Properly designed, wired, and grounded, spurious emissions from most coils will not cause a problem in the immediate household, much less outside. At very high power, when deliberately radiating, or when running out of tune; coils should be set up and operated in a shielded environment such as a Faraday cage or shielded rooms. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-17-94 03:05 From: Terry Smith To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS> ps: On thinking about FCC considerations, it's pretty TS> likely that these Tesla coils are highly in violation of TS> today's rules and regs. RQ> ps: You are twice now accusing me of being in "violation" of RQ> something you appear to know nothing (Tesla Coils) about??? RQ> My neighbors nextdoor don't have problem, why do you??? I haven't accused you of anything, but I have asked a few questions I strongly suspect, after considering some FCC implications, cannot be answered by anyone in the US in a way which makes most Tesla projects possible under current regulations. June on this year is the month when many engineers responsible for AM transmitters have to prove that spurious emmissions are in the microvolt range leaving their transmitter sites. In a sense that's another PITA nuisance I've had to spend hours handling, but it's one that anyone qualified to handle can understand as contributing to a worthwhile result. With current communications policy, lightning would probably be illegal if men controlled it. Those RF resources we do control are ever more tightly regulated, as spectrum is utilized by more tightly packed users having to share. The responsible ones among us try to do so without causing avoidable interference to others. I join many others here in expressing a curious interest in Tesla devices and technology. The more they're discussed, the more I suspect Don Kimberlin's comments about their becoming a legal "forbidden fruit" in the US are on target. RQ> If it means anything to you, this work has been going on RQ> since Faraday first discharged a capacitor. I take a Libertarian view of proper and legal US government function in general. In communications, there are cases where the FCC promotes political agenda issues due to improper politicking from the Hill. In general, I see the FCC as an agency which mostly functions to make communications needed for interstate commerce function. As such, I expect serious electronics operators to learn and follow pertinent regulations. Anyone pursuing projects involving megawatts and megavolts over a period of years certainly falls within that scope, IMHO. RQ> Well regardless: practical circuit assistance, capacitor (or RQ> coil) designs, or construction plans, spark gap ideas, RQ> grounding techniques, references, etc. are always welcome RQ> and appreciated. Regardless of legal implications, you've obviously developed a wealth of interesting knowledge, and some practical experience that's nearly impossible to refine based exclusively on theory. I've seen old spark gap transmitters in museums, originally operated at much lower powers than large Tesla coils. They don't get operated even for demos, as they can't operate legally under today's R&R. I personally am interested in seeing the Tesla threads continue, but is the answer to the "unintentional radiation" question that it's impossible to operate a large Tesla coil legally in the US, unless you do so on thousands of acres of private property? If so, and folks without huge buffer zones are making working units and discussing them here, this may be a more blatant "illegal use of FidoNet" than the kids holding criminal discussions of CB linears. Perhaps it's time to consult the echo moderator for an opinion on how he'd suggest this thread continue. Please dump the personal attacks. Back to the technology, do you know enough about the time/ frequency/power/conducted-induced-radiated signal relationships to answer the questions previously on the table, or to compare them for various coil designs, with and without the third tuning coil? Obviously it's a time/energy relationship which allows describing a single coil as 10 KVA, and also as 2 megawatts peak output. Since ionizing voltages are fairly standard calcu- lations, assuming predictable humidity, airborn dirt, and temperature conditions, I'd guess the previous voltage guesses may be close, but the peak currents exceed steady state averages by the inverse of the duty cycle, which the 2 MW figure for 10 KVA implies averages 0.5%. That still doesn't say much about how much variation is normal from a mathematical average. Would that be a range of perhaps 1 to 30 amps, or is there any practical means of estimating within any test setup you or Tesla have tried? As to the 6.78 MHz or other ISM frequencies, I strongly suspect that imitation lightning is inherently too wideband to possibly be confined to such allocated legal spectrum. Perhaps your research would confirm this? Spectrum over 3,000 GHz is also pretty much open, and available for crazy experiments by anyone getting a suitable HAM license. Obviously that's the "leftovers" from other users. In case you're wondering, I raised these ideas in consideration that sometimes there are legal options possible to shift the mode of old ideas and continue to pursue them. The fact that spark gap transmitters sit disconnected in museums illustrates the other possibility. Quite frankly, I'm amazed that megawatt surges haven't caused neighbors problems. You wouldn't believe how much of a nuisance much lower blanketting power levels can be, when one person installs some crap quality electronics, which passively transmit an interfering signal to neighbors. I've seen the AM and FM broadcast sides of that, and the HAMs see enough of it at even lower powers that the ARRL recently published several new guides of research results and suggested patches for assorted problems. If you ever get the chance to measure induced fields, which fall at an inverse cube rate, and radiated fields, which follow an inverse square law, that would be an interesting adjunct to the "raw power" research that's been described here. No harm meant, but please consider that there may be other serious aspects to this mix of research and high energy play... Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 22:18 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Terry Smith to Richard Quick <=- TS> ps: On thinking about FCC considerations, it's pretty TS> likely that these Tesla coils are highly in violation of TS> today's rules and regs. RQ> ps: You are twice now accusing me of being in "violation" of RQ> something you appear to know nothing (Tesla Coils) about??? RQ> My neighbors nextdoor don't have problem, why do you??? TS> I haven't accused you of anything, but I have asked a few TS> questions I strongly suspect, after considering some FCC ^^^^^^^ TS> implications, cannot be answered by anyone in the US in a TS> way which makes most Tesla projects possible under current TS> regulations. You are quite wrong in your suspicions. TS> The responsible ones among us try to do so without causing TS> avoidable interference to others. I completely agree, which is why I keep wondering why you keep posting me about this. TS> I join many others here in expressing a curious interest in TS> Tesla devices and technology. The more they're discussed, TS> the more I suspect Don Kimberlin's comments about their ^^^^^^^ TS> becoming a legal "forbidden fruit" in the US are on target. ^^^^^ ^^^^^^^^^ ^^^^^ You are talking of course about Tesla devices and technology like the 60 cycle power grid, the AC induction motor, the flyback transformer, the car distributor and the radio! These are all Tesla patented domain. You would declare them suspect in their legality and send us out to buy horses. What else are you suspicious of? TS> Regardless of legal implications, you've obviously developed ^^^^^ ^^^^^^^^^^^^ TS> a wealth of interesting knowledge, and some practical TS> experience that's nearly impossible to refine based TS> exclusively on theory. If you mean to say that I know what I am talking about, yes I do, and thank you for the complement. I get my hands dirty. TS> I've seen old spark gap transmitters in museums, originally TS> operated at much lower powers than large Tesla coils. They TS> don't get operated even for demos, as they can't operate TS> legally under today's R&R. ^^^^^^^ But you are again comparing transmitters and coils in the same sentence. On a transmitter you hang the proper antenna and you design the system to radiate a signal. On a coil you want to produce a spark. Two entirely different ideas, two entirely different designs; separate them in your mind. TS> With current communications policy, lightning would probably TS> be illegal if men controlled it. I am afraid you will have to E-Mail God on that one Terry. The FCC and the echo Moderator can't help you restrict an act of God. > This mish-mash continued in the next post ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 22:26 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ > Continued from Previous Post TS> I personally am interested in seeing the Tesla threads TS> continue, but is the answer to the "unintentional radiation" TS> question that it's impossible to operate a large Tesla coil TS> legally in the US, unless you do so on thousands of ^^^^^^^ TS> acres of private property? If you are such an expert on this subject, then why did you not simply state that the correct proceedure is to run radiating equipment in a properly shielded enviroment and let it go at that. A room shielded with hardware cloth and properly grounded seems much more reasonable (and works to the tune of 100% perfectly legal, even for transmitting type circuits) than your insinuation that I need to control thousands of acres of private property. You need to be: realistic, progressive, comprehensive, and intellegent; I am sorry if I just don't see that from you at this time. TS> ... this may be a more blatant "illegal use of FidoNet" than ^^^^^^^ TS> the kids holding criminal discussions of CB linears. TS> Perhaps it's time to consult the echo moderator for an TS> opinion on how he'd suggest this thread continue. TS> Please dump the personal attacks. Oh, please! Don't give me that "time to consult the echo moderator" line. Someone as "suspicious" as you are (please count the number of times you use this word when posting me); but not by any means "accusing" needs more help than you can get from a FIDO Electronics conference, or moderator for that matter. By even suggesting that you are thinking of calling upon the moderator, suggests that you are of a mind to accuse me of something. Feel free to consult with the moderator at any time you please. I have done nothing wrong. TS> Back to the technology, do you know enough about the TS> time/frequency/power/conducted-induced-radiated signal TS> relationships to answer the questions previously on the TS> table, or to compare them for various coil designs, with and TS> without the third tuning coil? Absolutely, where did you think I get my numbers? Make them up? Too many people here have see how I document my work. You are telling me that you are an expert with this math, as such I feel no need to work the equations for you. In other words; sharpen your own pencil. TS> Obviously it's a time/energy relationship which allows TS> describing a single coil as 10 KVA, and also as 2 megawatts TS> peak output. Very good. Go to the head of the class. TS> Since ionizing voltages are fairly standard calculations, TS> assuming predictable humidity, airborn dirt, and temperature TS> conditions, I'd guess the previous voltage guesses may be TS> close, but the peak currents exceed steady state averages by TS> the inverse of the duty cycle, which the 2 MW figure for 10 TS> KVA implies averages 0.5%. Not bad! You are pretty warm. That is exactly how I obtain my megawatt range peak powers. This is why quenching the main system spark gap is essential. The longer the main spark gap fires, the greater that ".5%" figure gets, and your peak powers are reduced correspondingly. See, I knew you could do it!!! TS> That still doesn't say much about how much variation is TS> normal from a mathematical average. Would that be a range of TS> perhaps 1 to 30 amps, or is there any practical means of TS> estimating within any test setup you or Tesla have tried? That variable may controled, and yes it can be measured with a current transformer on the primary. TS> As to the 6.78 MHz or other ISM frequencies, I strongly TS> suspect that imitation lightning is inherently too wideband ^^^^^^^ TS> to possibly be confined to such allocated legal spectrum. ^^^^^ Boy you are full of "legal" "suspicions" . Just look at the > ^^^^^ ^^^^^^^^^^^^ highlighting I have used in quoting just ONE of your posts!!! BTW, where did you come up with this frequency??? TS> Quite frankly, I'm amazed that megawatt surges haven't TS> caused neighbors problems. I am sorry to disappoint you. I have expended time and effort to ensure I am not a causing a problem. TS> ! Origin: Charges filed under Ohms Law! (203)732-0575 BBS ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Please look elsewhere to file your charges. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 23:29 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Just a recap of your method of communication: TS> I haven't accused you of anything... TS> ps: On thinking about FCC considerations, it's pretty TS> likely that these Tesla coils are highly in violation of TS> today's rules and regs. TS> strongly suspect, after considering some FCC implications, TS> Tesla devices and technology. The more they're discussed, TS> the more I suspect... about their becoming a legal TS> "forbidden fruit" TS> Regardless of legal implications... TS> .... they can't operate legally under today's R&R. TS> the "unintentional radiation" question that it's impossible TS> to operate a large Tesla coil legally TS> this may be a more blatant "illegal use of FidoNet" than the TS> kids holding criminal discussions of CB linears. Perhaps TS> it's time to consult the echo moderator for an opinion on TS> how he'd suggest this thread continue. TS> Please dump the personal attacks. TS> imitation lightning is inherently too wideband to possibly TS> be confined to such allocated legal spectrum. TS> are legal options possible to shift the mode of old ideas Of course it is clear you want me gagged, but you will maintain.. TS> No harm meant Let me make a suggestion before parting today. If you choose to post me by name again on this subject, would you be so kind as to tone it down some. You have maintained that you are not accusing me of anything, but to me the tone suggests otherwise. I am certain that since you are most definately not accusing me of anything, and you don't mean any harm, most of your statements and quotes above are corrupted and/or taken out of context. What you feel perhaps to be "personal attacks" (questions such as "do you have a day job?") are quite relevant as I deal with Tesla facts. Crackpots have already wasted too much of my valuable time on subjects about which they have no knowledge. Most of the crackpots who have crossed my path don't work during the day, and have plenty of time to waste mine. Tesla Coiling is a legal, educational, and entertainable, hobby. Like many powerful tools and instruments; there is a potiental for misuse and abuse by unscrupulous persons. Safe and proper use requires education. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 11:34 From: Jamar Neal To: Richard Quick Subj: Re: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ > Tesla was not able to get a construction contract with his >system in the United States, but he was awarded a contract in >Canada. He delivered sketches and specifications to Westinghouse >for a system to generate hydroelectric power from the Niagara >river for the commercial production of aluminum 20 miles away. >The high voltage transmission was very economical. It appears >that Tesla agreed to a one-time payment of one million dollars, >and the 60 cycle patents remained with Westinghouse. The money >was spent in the lab developing his next generation projects. > Tesla's system was universally adopted in one country after > another, yet Edison gets credit for lighting the world. So Tesla was the brains behind Westinghouse? I have read a few books on Edision and it was never mentioned that Tesla worked there (I have to pick my book better :-)) Edision often gets credit for lighting the world...but that is because of the light bulb. I think most people know that his DC idea lost out. Jamar 314-339-0248 (1:287/516) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-18-94 19:21 From: Bob Patten To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> There is an excellent article in the latest issue of the Tesla -> Coil Builders Association (TCBA) publication, "NEWS" (vol. 13, -> #3 Jul,Aug,Sep,'94) on high powered coiling (36" spark lengths -> running three #833 power tubes, 8+ KVA). The previous issue -> ran an article on a 5.2 mHz, pulse generator driven, coil. -> ............................................................ -> Yeah, this is base feeding a 1/4 wave resonator with a high -> current signal, a-la Colorado Springs. High Q resonators can -> produce some pretty decent voltage rises, as witnessed by the -> spark discharge and corona. Your efficiency in the resonator -> had to be good, with a nice frequency and impedance match. Thanks again, Richard! I did a hard copy of this message also and will study it. I'm a real novice at this and need to sort out a lot of info and get a better understanding of it. Today, I received in the mail a package from the Int'l Tesla Society which included a comprehensive listing of the publications they have available. I would imagine you are familiar with what's available and wonder if you have any further recommendations. At this point, I'm not sure if I want to build the conventional spark gap type coil or go for a tube type... Cost and availability of parts are prime factors.. Tnx agn. 73, BP ! Origin: Bashful Pervert BBS (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 22:04 From: Don Kimberlin To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> DK> ...all the more important then, in the case of those who DK> would build Tesla coils today, that they understand how DK> to make really high-efficiency ones, then, eh? I know an DK> awful lot of the Pop-Tronics "projects" of the old magazines DK> resulted in awfully sloppy things that thrilled people with DK> six inches or a foot of discharge, which worked out to a DK> horrible inefficiency for the input they were running.... RQ>The goal should always be maximum efficiency. This is the RQ>major reason that Tesla himself left two coil systems behind, RQ>and developed the three coil system (primary, secondary, extra RQ>coil) to industrial scale. But even some experienced coilers RQ>need to learn the "rules of the road" when it comes to simple RQ>coils. RQ>A heavy, dedicated, RF ground is a must for any serious RQ>coiling. Experiments should then seek to convert every RQ> possible watt into spark, where the energy is consumed as RQ>heat, light, sound, etc.. RQ>The coil base wire is the source of most of the spurious RQ>signal. The output here is a low voltage RF current at quite a RQ>few rms amps. The signal seems to conduct better than it RQ>radiates, so just make sure your ground path is equipped for RQ>it. RQ>Remember too that spark gap Tesla Coils are disruptive. The RQ>output from coils excited by spark gap tank circuits does not RQ>radiate well, and is a far cry from CW. Properly designed, RQ>wired, and grounded, spurious emissions from most coils will RQ>not cause a problem in the immediate household, much less RQ>outside. At very high power, when deliberately radiating, or RQ>when running out of tune; coils should be set up and operated RQ>in a shielded environment such as a Faraday cage or shielded RQ>rooms. ...Looks like we're here in an environment where the emphasis is on a maximum induction field, which is kind of interesting, because most everything we have done in later times is to attempt to minimize the induction field, or at least let it die out at short range. Conversely, it appears the first "radio" people, and I note even Marconi when in his low-frequency radio years (before his stuff was for all practical purposes expropriated by both the British and U.S. governments), was concerned with trying to make maximum use of the induction field. There's quite a bit of debate about a Kentuckian named Stubblefield who appears to have made a "radio" that used an induction field, and he's been rather discredited for having done so. ...My own background in high-powered radio (and Terry Smith's, btw) have taught us both about the important of a low-reactance interface to earth. I grew up down in Florida's "lightning alley" and have repeatedly had to try to teach the lesson about the need for low-reactance paths to earth there -- seen people lose literally millions of dollars worth of electronics and electrical hardware, plus unmeasurable amounts of business production for trying to ignore it in that part of the country. ...So, are those "three-coil" Tesla coils connected in a sort of induction-aiding 120 degree phase relation, rather than simple, shall we call it, "push-pull," or is the object more in the form of trying to maintain the average higher so the peak can get even higher than in a 180 degree arrangement? Concord,N.C. (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-14-94 16:51 From: Richard Quick To: Michael Scott Subj: Tesla Coils, Video ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Mike, Thanks for the nice letter. Your video tape was posted this morning, you should receive it shortly after you get this post. I included a disk with many related text files. It should make for some interesting reading, as the archived material goes back over six months. If you have any problems, questions, comments, corrections, etc., please post me. Do let me know that you have received your video, and let us know what you think. Thanks again; Richard Quick ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-17-94 20:20 From: Richard Quick To: Sjoerd Schaafsma Subj: Tesla Coils, Video ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> If you have any problems, questions, comments, corrections, RQ> etc., please post me. Since your tape was sent out of the RQ> country I would appreciate it if you would let me know when RQ> it arrives. SS> Thanks a bunch Richard, I'll let you know... That turn-around was fast. This lap around should catch you with my video in your mailbox. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-14-94 16:56 From: Richard Quick To: Sjoerd Schaafsma Subj: Tesla Coils, Video ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Sjoerd, Your video tape was posted this morning too. Since you are not in the states it will be a week or more before it arrives, though I did pay for first class air service. I included the disk with the text files. If you have any problems, questions, comments, corrections, etc., please post me. Since your tape was sent out of the country I would appreciate it if you would let me know when it arrives. Thanks again; Richard Quick ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-22-94 15:49 From: Richard Quick To: Jamar Neal Subj: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ > Tesla's system was universally adopted in one country after > another, yet Edison gets credit for lighting the world. JN> So Tesla was the brains behind Westinghouse? Oh yes, absolutely. A very good book on the subject is published by Barnes and Nobel: TESLA, Man Out of Time Margaret Cheney, 1981, published by Dorset Press, ISBN 0-88029- 419-1; available from Barnes & Nobel, 126 Fifth Ave., New York, NY, 10011, tel:201-767-7079. 320pp, hardcover, catalog #1611151, $7.98 US. They carry another Tesla title: The Inventions, Researches & Writtings of Nikola Tesla, 1893, N.Tesla (edited and prefaced by Thomas Commerford Martin), ISBN 0-88029-812-X, published by Barnes & Nobel (1992 second edition). 512pp, hardcover, catalog #1774447, $9.98 JN> I have read a few books on Edision and it was never JN> mentioned that Tesla worked there (I have to pick my book JN> better :-)) Edision often gets credit for lighting the JN> world...but that is because of the light bulb. I think most JN> people know that his DC idea lost out. Well the second book I listed, by Tesla, is a transcript of some of his lectures. It pretty much lays out his idea of generator/motor power transmission systems and covers some of his lighting work. The Complete Patents will show parallel development in mechanics and electromechanics. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-21-94 20:41 From: Richard Quick To: Bob Patten Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BP> I'm a real novice at this and need to sort out a lot of BP> info and get a better understanding of it. Today, I BP> received in the mail a package from the Int'l Tesla Society BP> which included a comprehensive listing of the publications BP> they have available. I would imagine you are familiar with BP> what's available and wonder if you have any further BP> recommendations. At this point, I'm not sure if I want to BP> build the conventional spark gap type coil or go for a tube BP> type... Cost and availability of parts are prime factors.. I wish I could recommend the definitive book on Tesla coiling, but I have read them all, and I still have not read IT. But if you want to start for next to nothing you should wind a coil and fire it from a spark excited tank circuit. This is definately the way to go for a buck novice. A good tube tank circuit will run quite a few bucks over what a good spark excited tank circuit will cost. You can start both at the same place by winding a 4" coil with a resonate frequency of around 450 kHz, or preferably a little higher. Get some rigid Plexi, Lexan, or polystyrene pipe/tubing with a thin wall. It should be ~4 inches in diameter and 21 inches long. Thin wall PVC drain pipe may be used but it must be sanded, dried throughly, and sealed with several coats of polyurethane or clear two-part epoxy paint. Buy at least 1-1/4 lbs (~1000 feet in length) of #24 double Formvar (enamel) covered magnet wire. Wind the wire on the coil form. The windings needs to be tightly spaced, no gaps, and no overlaps: the winding should start 1" above the bottom of the coil form. #24 magnet wire winds about 46 turns per inch (TPI), the winding should be 19 inches long with ~874 turns, and use up about 915 feet of the wire. The winding should stop about 1" below the top of the coil form. Use tape, hot glue, or clear epoxy to affix the top and bottom turns of the coil winding. Never drill holes or introduce wire inside the coil form. Once wound, the windings should be sealed with several coats of polyurethane or clear two-part epoxy paint. After the windings are sealed, I cap the top and bottom of the coil form with disks of plexiglass bedded in epoxy. This coil is modern. It offers the maximum inductance per unit volume of coil form in a high Q design. It will work very well in a spark, or tube, driven tank circuit of moderate power. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-21-94 22:18 From: Richard Quick To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Talking about Tesla Coils... DK> ...Looks like we're here in an environment where the DK> emphasis is on a maximum induction field, which is kind of DK> interesting, because most everything we have done in later DK> times is to attempt to minimize the induction field, or at DK> least let it die out at short range. Yes. A Tesla coil is a resonate transformer. The "transformer" part means that the system involves energy exchange by induction. But it is not simply producing a "maximum induction field", but of producing a field of proper intensity and shape around a resonate inductive structure (coil). It boils down to proper mutual inductance between primary and secondary, known to coilers as "the coefficient of coupling". DK> Conversely, it appears the first "radio" people, DK> and I note even Marconi when in his low-frequency radio DK> years... Bahh, Marconi worked for Tesla for nearly a year, before 1891, and stole a lot of technique, not to mention nine key patents. I am adverse to crediting thieves. DK> ...My own background in high-powered radio (and Terry DK> Smith's, btw) have taught us both about the important of a DK> low-reactance interface to earth. Tesla was the first to apply ground to a tuned circuit if that says anything. No ground used in Tesla work can be too heavy. DK> I grew up down in Florida's "lightning alley" and have DK> repeatedly had to try to teach the lesson about DK> the need for low-reactance paths to earth there -- seen DK> people lose literally millions of dollars worth of DK> electronics and electrical hardware, plus unmeasurable DK> amounts of business production for trying to ignore it in DK> that part of the country. And it seems no ground used for lightning can be too heavy. DK> ...So, are those "three-coil" Tesla coils connected in a DK> sort of induction-aiding 120 degree phase relation, rather DK> than simple, shall we call it, "push-pull," or is the object DK> more in the form of trying to maintain the average higher so DK> the peak can get even higher than in a 180 degree DK> arrangement? The third coil is not inductively coupled to the primary/ secondary. The best way to describe the third coil is to simply call it an uncoupled resonator which is base fed by transmission line. The transmision line I commonly use is simply a heavy conductor run from the top of the secondary to the base of the extra coil some distance away. Adding the extra coil causes a shift in the secondary output from 90 degrees (1/4 wave) to 45 degrees (1/8) wave in the most efficient experimental systems. This means the secondary is no longer sparking, but shifts to supplying current, by way of transmission line, to the uncoupled third coil. This third coil is allowed to resonate freely, unrestricted by the inductive coupling between primary and secondary. It has the effect of allowing circuit designs and/or modifi- cations which breaks the 50% efficiency barrier for resonate transformers. I believe three coil designs are possible that are as high as 95% efficient. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-22-94 01:06 From: Terry Smith To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>The goal should always be maximum efficiency. This is the RQ>major RQ>A heavy, dedicated, RF ground is a must for any serious RQ>coiling. Experiments should then seek to convert every RQ>possible watt into spark, where the energy is consumed as RQ>heat, light, sound, etc.. The coil base wire is the source of most of the spurious signal. DK> ...Looks like we're here in an environment where the DK> emphasis is on a maximum induction field, which is kind of DK> interesting, I always thought emphasis at RF on radiated rather than induced fields was chosen because of the square versus cube function signal decline with distance. Induction, conversely, seems preferred for closed system industrial processes. DK> ...My own background in high-powered radio (and Terry DK> Smith's, Nah... I've never played with the stuff over 60 KW. DK> btw) have taught us both about the important of a DK> low-reactance interface to earth. I grew up down in DK> Florida's "lightning From this thread, I'm getting an impression that broadcasters do a little more in the way of operating impedance calculations and measurements, and projected ground related base losses, than folks who stare in awe at man made lightning. On a broadcast tower, with a 30 ohm self impedance, but a 10 ohm operating impedance in an array, a resistance to earth (half the radiator, as well as the coupling plane) of 3 ohms, when 1 ohm is practical, makes a big difference. DK> alley" and have repeatedly had to try to teach the lesson DK> about the need for low-reactance paths to earth there -- seen DK> people lose literally millions of dollars worth of DK> electronics and electrical hardware, plus unmeasurable DK> amounts of business production for trying to ignore it in DK> that part of the country. Have you ever seen anyone explode a concrete building floor slab? That's one I've only heard of, where someone had the brilliant idea of using reinforcing mesh in the slab as a cheap alternative to normal "open land" ground electrodes, rods, screens, bonded radials, etc. Up these parts, we get winter. Down your way, I guess you're more likely to see a glass encapsulated (and therefore insulated) ground rod, from lightning melting the quartz sand around the rod? If Richard, or anyone cares to comment, what have Tesla experimenters used for ground references? For those larger coils, I would suspect an array of radials using a few miles of #10 soft drawn Cu, with Erico welded mesh for about 50' in the center, bonded with 4" strap, might be adequate in most places. Add a couple of 30' chemical grounding electrodes in poor soil areas. Does anyone bother in high voltage experiments? Terry Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-21-94 17:07 From: Mark Conway To: Richard Quick Subj: crossed wires ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TID: FastEcho 1.40 15032 Hi Richard, This is a repost as my original message seems to have gotten lost in the system. I think we have been having a few problems with fidonet lately. Anyway if you have already recieived this message then please ignore it. Hey I have just finished watching your 2 videos on tesla coils ( I got copies from Jim Oliver)- boy talk about impressive! I think I would be too chicken to use a power pig to power a tesla coil - I guess if you want to go into even higher powers you will need your own nuclear generator, or maybe you could wire up a lightning rod and use a lightning strike as the input power for your tesla coil- one advantage of this I spose is that you wouldnt have to worry about a spark gap or a capacitor! In your reply to my last message about crossing turns on a tesla coil you said, The problem with crossing wires, especially on base fed coils (such as Duane Bylunds) is that the lower turns can act as a low voltage "ground" point. Crosses between turns (especially on short fat coils with high interturn voltage increases) results in tiny breakdowns in the magnet wire insulation. These breakdowns cause excessive losses. Another way to look at it is that each overlapped turn represents an intermittant short circuit.Ó I still arent quite sure how this works- wouldnt the turns just being wound close together constitute an intermittant short circuit or does the wire being crossed mean that their will be a sharp point somewhere on the crossed wires that will result in electrical breakdown? Thanks for the info on salt bottle capacitors. I calculated that to get a capacitance of 0.02 microfarad (which is what the circuit in the tesla coil article says is required) I would need 66 big beer bottles. Ive started collecting beer bottles (hic- the things I have to do for science!) but I think that it will probably be too bulky. I have your postings on making polyethylene caps. I would like to try making these but I am not too sure about the availability of the materials here in NZ. Is polyethylene the same as polythene - is it the black sheet stuff that people use for laying on their gardens to stop weeds poking through? If it is the same then I will have no problem in locating a supply. If it isnt could you please tell me what polyethylene is used for in the States and maybe I could find a supply of it over here. Aluminium flashing looks like it could also be difficult to find over here. Is it used for plumbing or roofing over there? Best Regards, Mark: Infomania! - 64-9-489-6750 (3:772/195) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-22-94 18:54 From: Bob Patten To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> I wish I could recommend the definitive book on Tesla coiling, -> but I have read them all, and I still have not read IT. I sent for two books yesterday, "Vacuum Tube Tesla Coils" and "100 Years of Electrical Magic". Thank you for the detailed description of how to wind a 450 khz coil. Again, I've made a hard copy of your message. With the info that you've given me and the books that are on order, I'll have plenty of material to study when I go on vacation in just under two weeks. Oh yes, I did build an induction coil setup using a K-Mart universal ignition coil and a 555 timer. It worked quite well with various types of lamps including flourescent and a splendid Jacob's ladder. This satisfied my immediate craving, but I still intend to build a Tesla Coil, something I've thought about since I was a kid - about 40 years ago... Thanks for your help! (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-23-94 21:17 From: Roy J. Tellason To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Some of these comments are based on my recollection of that long-ago article that appeared in Popular Electronics... 21 Jun 94, Richard Quick writes to Bob Patten: RQ> Get some rigid Plexi, Lexan, or polystyrene pipe/tubing with RQ> a thin wall. It should be ~4 inches in diameter and 21 RQ> inches long. Thin wall PVC drain pipe may be used but it RQ> must be sanded, dried throughly, and sealed with several RQ> coats of polyurethane or clear two-part epoxy paint. They used a cardboard tube for this, a readily available item, but I'm sure that a lot of the other materials you mention weren't around in those days. RQ> Buy at least 1-1/4 lbs (~1000 feet in length) of #24 double RQ> Formvar (enamel) covered magnet wire. I seem to remember that article mentioning two pounds of wire, but I can't remember what size wire it was. RQ> Wind the wire on the coil form. Is there any easy way to do this? :-) When I was in junior high school we had a little gimmick that consisted of most of the parts of a hand drill mounted on a board, but those were multi-layer coils wound with fabric- covered wire that sort of resembled the kind of thing that you'd see in a doorbell or buzzer. I can't quite see sticking a four-foot cardboard tube into one of these, though. RQ> The windings needs to be tightly spaced, no gaps, and no RQ> overlaps: the winding should start 1" above the bottom of RQ> the coil form. #24 magnet wire winds about 46 turns per inch RQ> (TPI), the winding should be 19 inches long with ~874 turns, RQ> and use up about 915 feet of the wire. The winding should RQ> stop about 1" below the top of the coil form. That's pretty explicit stuff, there. RQ> Never drill holes or introduce wire inside the coil form. That article referred to wooden disks in each end of the form, with the bottom one having something or other to support the thing and the top one having a big (3-4") feedthrough insulator mounted on it. RQ> After the windings are sealed, I cap the top and bottom of RQ> the coil form with disks of plexiglass bedded in epoxy. What do you mean "bedded in epoxy"? RQ> ... If all else fails... Throw another Megavolt across it! Sounds good to me! ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-23-94 18:53 From: Richard Quick To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Discussing low impedance grounds in RF work, xmitters and Tesla coils. TS> From this thread, I'm getting an impression that TS> broadcasters do a little more in the way of operating TS> impedance calculations and measurements, and projected TS> ground related base losses, than folks who stare in awe at TS> man made lightning. Must we be forever in disagreement Terry? Earth ground was first applied to a tuned circuit by the man who created synthetic lightning. The same man who invented broadcasting, and a ground based electrical transmission system which requires no wires. How could you say that the followers of the man who first calculated these figures would be ignorant of his work? I will refer you first to Tesla's own writings: Colorado Springs Notes, 1899-1900, Nickola Tesla, Nolit, Beograd, Yugoslavia, 1978, pp12. Tesla writes a list of three major goals for the experimental lab he is constructing in Colorado Springs. Number three on the list: NT> 3. To ascertain the laws of propagation of currents through NT> the earth and the atmosphere. The diagrams, footnotes, and patent references from pp12-18 alone would be sufficient to convince you the error of your implication. If that is not enough, then I would refer you to the pp36-37 entries for mid-month, June 15-17, 1899. Tesla proceeds to construct a system ground for the oscillator, followed by electrical measurement of both the system ground and the water pipe main supplying the lab. In later work all of the major earth resonate frequencies were plotted with amazing accuracy. The O'scope had to wait years to be invented. In the 1950's Schumann, Bremmer, Budden, Wait, Galejs and other authors verified all of Tesla's "ground" work step by step. See: > Terrestrial Propagation of Long Electromagnetic Waves J. Galeys, New York, Pergamon Press, 1972 DK> alley" and have repeatedly had to try to teach the lesson DK> about the need for low-reactance paths to earth there -- TS> "open land" ground electrodes, rods, screens, bonded TS> radials, etc. I knew we would agree somewhere. I have been stating this here for a year now. TS> If Richard, or anyone cares to comment. What have Tesla TS> experimenters used for ground references? Me not comment? Well I can't speak for everone, but I have listed references above that you would obviously find informative. TS> For those larger coils, I would suspect an array of radials TS> using a few miles of #10 soft drawn Cu, with Erico TS> welded mesh for about 50' in the center, bonded with 4" TS> strap, might be adequate in most places. Add a couple of TS> 30' chemical grounding electrodes in poor soil areas. Does TS> anyone bother in high voltage experiments? I ground my stuff to a buried hydraulic lift. The lift assembly consists of a large buried oil tank, air tank, supply and control plumbing, and the actual steel piston assembly. Run from this ground point (which is all metal spread out over 225 square feet) are two 1" ground straps; one strap runs to connect buried decorative pond (1500 gallon galvinized steel tank), the second runs to a 50' length of 14" wide aluminum flashing submerged in a nearby creek bed. All coil connections to this ground are 15' feet or less for the high powered stuff. I use the equivalent of a 2-1/2" grounding strap from the base of the coil, and the safety gap center post, to the lift control plumbing (both copper and galvinized steel pipe) where it enters the ground. While the grounding system you document would be ideal, mine functions. I do have some idea of what I am doing. I have also done extensive experimentation on coil systems and their grounding requirements. I have followed Tesla's footsteps carefully in many respects. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 11:34 From: Jamar Neal To: Richard Quick Subj: Re: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ > Tesla was not able to get a construction contract with his > system in the United States, but he was awarded a contract in > Canada. He delivered sketches and specifications to > Westinghouse for a system to generate hydroelectric power from > the Niagara river for the commercial production of aluminum 20 > miles away. The high voltage transmission was very economical. > It appears that Tesla agreed to a one-time payment of one > million dollars, and the 60 cycle patents remained with > Westinghouse. The money was spent in the lab developing his > next generation projects. > Tesla's system was universally adopted in one country after > another, yet Edison gets credit for lighting the world. So Tesla was the brains behind Westinghouse? I have read a few books on Edision and it was never mentioned that Tesla worked there (I have to pick my book better :-)) Edision often gets credit for lighting the world...but that is because of the light bulb. I think most people know that his DC idea lost out. Jamar 314-339-0248 (1:287/516) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-18-94 19:21 From: Bob Patten To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -> There is an excellent article in the latest issue of the Tesla -> Coil Builders Association (TCBA) publication, "NEWS" (vol. 13, -> #3 Jul,Aug,Sep,'94) on high powered coiling (36" spark lengths -> running three #833 power tubes, 8+ KVA). The previous issue -> ran an article on a 5.2 mHz, pulse generator driven, coil. -> ............................................................ -> Yeah, this is base feeding a 1/4 wave resonator with a high -> current signal, a-la Colorado Springs. High Q resonators can -> produce some pretty decent voltage rises, as witnessed by the -> spark discharge and corona. Your efficiency in the resonator -> had to be good, with a nice frequency and impedance match. Thanks again, Richard! I did a hard copy of this message also and will study it. I'm a real novice at this and need to sort out a lot of info and get a better understanding of it. Today, I received in the mail a package from the Int'l Tesla Society which included a comprehensive listing of the publications they have available. I would imagine you are familiar with what's available and wonder if you have any further recommendations. At this point, I'm not sure if I want to build the conventional spark gap type coil or go for a tube type... Cost and availability of parts are prime factors.. Tnx agn. 73, (305) 472-7715 (1:369/120) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-19-94 22:04 From: Don Kimberlin To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> DK> ...all the more important then, in the case of those who DK> would build Tesla coils today, that they understand how to DK> make really high-efficiency ones, then, eh? I know an awful DK> lot of the Pop-Tronics "projects" of the old magazines DK> resulted in awfully sloppy things that thrilled people with DK> six inches or a foot of discharge, which worked out to a DK> horrible inefficiency for the input they were running.... RQ>The goal should always be maximum efficiency. This is the RQ>major reason that Tesla himself left two coil systems behind, RQ>and developed the three coil system (primary, secondary, extra RQ>coil) to industrial scale. But even some experienced coilers RQ>need to learn the "rules of the road" when it comes to simple RQ>coils. RQ>A heavy, dedicated, RF ground is a must for any serious RQ>coiling. Experiments should then seek to convert every RQ>possible watt into spark, where the energy is consumed as RQ>heat, light, sound, etc.. RQ>The coil base wire is the source of most of the spurious RQ> signal. RQ>The output here is a low voltage RF current at quite a few rms RQ>amps. The signal seems to conduct better than it radiates, so RQ>just make sure your ground path is equipped for it. RQ>Remember too that spark gap Tesla Coils are disruptive. The RQ>output from coils excited by spark gap tank circuits does not RQ>radiate well, and is a far cry from CW. Properly designed, RQ>wired, and grounded, spurious emissions from most coils will RQ>not cause a problem in the immediate household, much less RQ>outside. At very high power, when deliberately radiating, or RQ>when running out of tune; coils should be set up and operated RQ>in a shielded environment such as a Faraday cage or shielded RQ>rooms. ...Looks like we're here in an environment where the emphasis is on a maximum induction field, which is kind of interesting, because most everything we have done in later times is to attempt to minimize the induction field, or at least let it die out at short range. Conversely, it appears the first "radio" people, and I note even Marconi when in his low-frequency radio years (before his stuff was for all practical purposes expropriated by both the British and U.S. governments), was concerned with trying to make maximum use of the induction field. There's quite a bit of debate about a Kentuckian named Stubblefield who appears to have made a "radio" that used an induction field, and he's been rather discredited for having done so. ...My own background in high-powered radio (and Terry Smith's, btw) have taught us both about the important of a low-reactance interface to earth. I grew up down in Florida's "lightning alley" and have repeatedly had to try to teach the lesson about the need for low-reactance paths to earth there -- seen people lose literally millions of dollars worth of electronics and electrical hardware, plus unmeasurable amounts of business production for trying to ignore it in that part of the country. ...So, are those "three-coil" Tesla coils connected in a sort of induction-aiding 120 degree phase relation, rather than simple, shall we call it, "push-pull," or is the object more in the form of trying to maintain the average higher so the peak can get even higher than in a 180 degree arrangement? ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 16:37 From: Richard Quick To: Mark Conway Subj: crossed wires ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ MC> This is a repost as my original message... No, I never saw the first one. MC> Hey I have just finished watching your 2 videos on tesla MC> coils ( I got copies from Jim Oliver)- boy talk about MC> impressive! Thank you for the vote of confidence. MC> .... crossing turns on a tesla coil... RQ> ... the lower turns can act as a low RQ> voltage "ground" point. Crosses between turns (especially on RQ> short fat coils with high interturn voltage increases) RQ> results in tiny breakdowns in the magnet wire insulation. RQ> These breakdowns cause excessive losses. Another way to look RQ> at it is that each overlapped turn represents an RQ> intermittant short circuit. MC> I still arent quite sure how this works- wouldnt the turns MC> just being wound close together constitute an intermittant MC> short circuit or does the wire being crossed mean that their MC> will be a sharp point somewhere on the crossed wires that MC> will result in electrical breakdown? OK, first off my use of the word "ground" should better be described as an electrical node. The base of a coil is a low voltage electrical nodal point. The voltage in a Tesla coil rises as the wire get closer to the 1/4 wave, or high voltage, node (usually the air terminal). Since the voltage rises steeply up the coil, high interturn voltages exist. When turns are crossed, micropunctures can develop in the enamel insulation at the location of the overlap. No sharp point is required for insulation breakdown in coil resonators. MC> to get a capacitance of 0.02 microfarad... MC> ... I think that it will probably be too bulky. I know a guy that used 5 gallon plastic (polyethyene) buckets full of salt water and nested together... MC> Is polyethylene the same as polythene - is it the black MC> sheet stuff that people use for laying on their gardens to MC> stop weeds poking through? Yes, my MERCK index indentifies "Polythene" as a brand name for polyethylene. The polyethylene grade used for coiling is a milky-clear plastic sheeting, used in the construction trade for waterproofing, or sold by the yard from plastic specialist. Thinner grades (measured in thousandths of inches here) are typically 4-10 mils thick for plastic freezing bags, trash bags, drop cloths, etc. MC> Aluminium flashing looks like it could also be difficult to MC> find over here. Is it used for plumbing or roofing over MC> there? Roofing, edging. It is sold here by the roll in hardware stores. It is stiff sheet aluminum, cut into a strip say 14 inches wide and 50 feet long. The strip is rolled up for retail sale. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-22-94 14:51 From: Don Kimberlin To: Jamar Neal Subj: Re: Tesla ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ JN>So Tesla was the brains behind Westinghouse? I have read a JN>few books on Edision and it was never mentioned that Tesla JN>worked there (I have to pick my book better). ...I have an English-written book that makes a bit of mention of Tesla's contributions to Westinghouse...but it then goes on to tell more about the acrimonious debate over AC versus DC power. They even had some incredibly stupid things like getting the Prince of Wales to hold some DC wires, to "prove" that DC was "harmless to humans!" JN>Edison often gets credit for lighting the world...but that is JN>because of the light bulb. I think most people know that his JN>DC idea lost out. ...ah, but the British history also mentions a Swan in England who they claim beat Edison to the lightbulb punch. Edison fought quite a patent battle with Swan in England and wound up getting a draw at best...and Swan wound up making the light bulbs there, as I recall from the book (need to check it again before saying that for certain...) Concord,N.C. (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 16:54 From: Richard Quick To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Talking about coil construction... RQ> Get some rigid Plexi, Lexan, or polystyrene pipe/tubing with RQ> a thin wall. RJT> They used a cardboard tube for this, a readily available RJT> item, PVC thin wall plastic "drain" pipe that has been sanded and sealed is generally better than cardboard. RJT> but I'm sure that a lot of the other materials you mention RJT> weren't around in those days. No modern materials were not around, but this does not mean they should not be used. Older coils were plagued with low efficiency and unreliable operation. Many "classic" coils and projects of this nature were full of errors and misconceptions. With modern materials (and designs and schematics that utilize them) at my fingertips I would never look back. RQ> Wind the wire on the coil form. RJT> Is there any easy way to do this? :-) I set up a spindle through the center of the coil form, and roll the form with one hand while feeding wire with other. RJT> That article referred to wooden disks in each end of the RJT> form,..., RQ> I cap the top and bottom of the coil form with disks of RQ> plexiglass bedded in epoxy. RJT> What do you mean "bedded in epoxy"? I mean smear a thick enough bead of epoxy on the cap and the end of the coil form so that the epoxy is forced out when the parts are fitted. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 07:50 From: Dave Mcknight To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS>If Richard, or anyone cares to comment, what have Tesla >experimenters used for ground references? For those larger >coils, I would suspect an array of radi using a few miles of >#10 soft drawn Cu, with Erico welded mesh for about 50'the >center, bonded with 4" strap, might be adequate in most >places. Add a couple of 30' chemical grounding electrodes in >poor soil areas. Does anyone bother in high voltage >experiments? I'm just getting into Tesla experimenting myself. For my small coils I use two 5' copper pipes driven 6 feet under, about 5' apart. These are connected together and run to my garage with 2 10ga. copper cables. When I'm running the power up, I take the garden hose out and soak down the area before firing the coil. Your mention of "chemical grounding electrodes" intrigues me. Can you suggest a chemical that I could soak into this area to enhance the grounding without destroying my lawn? When planting my grounds I scooped off the sod then dug out about 1 ft. of dirt before driving the rods, then reburied the tops after I finished. No mowing problems, no copper pegs for kids to trip and injure themselves on. Since the stakes are in the middle of my lawn, something like rock salt would probably not be beneficial. (614)861-8377 (1:226/110) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Msg#: 7532 Rec'd Date: 06-24-94 10:47 From: Don Kimberlin Read: Yes Replied: Yes To: Richard Quick Mark: Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ ÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>Talking about Tesla Coils... RQ> DK> ...Looks like we're here in an environment where the DK> emphasis is on a maximum induction field, which is kind of DK> interesting, because most everything we have done in later DK> times is to attempt to minimize the induction field, or at DK> least let it die out at short range. RQ>Yes. A Tesla coil is a resonate transformer. The "transformer" RQ>part means that the system involves energy exchange by RQ>induction. But it is not simply producing a "maximum induction RQ>field", but of producing a field of proper intensity and shape RQ>around a resonate inductive structure (coil). ...OK, that sounds like there is concern for somehow "shaping" the induction field around a core, rather than merely letting it assume some random proportions, and attempting to couple to it. Or am I zooming off on a tangent? RQ>It boils down to proper mutual inductance between primary and RQ>secondary, known to coilers as "the coefficient of coupling". ...Oh, boy, shades of some of the most hateful questions on the old FCC First Class license test from back in the 1950's! RQ> DK> Conversely, it appears the first "radio" people, RQ> DK> and I note even Marconi when in his low-frequency radio RQ> DK> years... RQ>Bahh, Marconi worked for Tesla for nearly a year, before 1891, RQ>and stole a lot of technique, not to mention nine key patents. RQ>I am adverse to crediting thieves. ...Now, THAT's interesting to me! So Marconi hung around Tesla, eh? All the histories I've read seem to make no mention of any connection between them. They at best describe Marconi as having had the advantage of being wealthy, then marrying a daughter of the Irish Jameson (whisky) family, which got him into British society after the Italians ignored his efforts...I *must* get into a Tesla history book one of these days! RQ> DK> ...My own background in high-powered radio (and Terry DK> Smith's, btw) have taught us both about the important of a DK> low-reactance interface to earth. RQ>Tesla was the first to apply ground to a tuned circuit if that RQ>says anything. No ground used in Tesla work can be too heavy. ...It may, in fact, really say something, because what we seem to see in the histories is Hertz in his physics lab, with everything balanced and floating above ground, then Marconi tying "radio" to ground. Certainly makes sense that Tesla conceived of that change to use the earth for one side of the circuit... RQ> DK> I grew up down in Florida's "lightning alley" and have RQ> DK> repeatedly had to try to teach the lesson about RQ> DK> the need for low-reactance paths to earth there -- seen RQ> DK> people lose literally millions of dollars worth of RQ> DK> electronics and electrical hardware, plus unmeasurable RQ> DK> amounts of business production for trying to ignore it in RQ> DK> that part of the country. RQ>And it seems no ground used for lightning can be too heavy. SET JOHN_WAYNE.SYS /on ...yuh got that right, Pilgrim. People have a hard time with the concept that the earth does not have unlimited ability to conduct electricity away from a point contact. Oh, electric power engineers know this, but the general public...and strangely enough, even modern EE's working on PC boards have to grasp the notion about peak pulse currents in a "ground plane" on a PC board. RQ> DK> ...So, are those "three-coil" Tesla coils connected in a DK> sort of induction-aiding 120 degree phase relation, rather DK> than simple, shall we call it, "push-pull," or is the object DK> more in the form of trying to maintain the average higher so DK> the peak can get even higher than in a 180 degree DK> arrangement? RQ>The third coil is not inductively coupled to the primary/ RQ>secondary. The best way to describe the third coil is to RQ>simply call it an uncoupled resonator which is base fed by RQ>transmission line. The transmision line I commonly use is RQ>simply a heavy conductor run from the top of the secondary to RQ>the base of the extra coil some distance away. RQ>Adding the extra coil causes a shift in the secondary output RQ>from 90 degrees (1/4 wave) to 45 degrees (1/8) wave in the RQ>most efficient experimental systems. This means the secondary RQ>is no longer sparking, but shifts to supplying current, by way RQ>of transmission line, to the uncoupled third coil. This third RQ>coil is allowed to resonate freely, unrestricted by the RQ>inductive coupling between primary and secondary. RQ>It has the effect of allowing circuit designs and/or modifi- RQ>cations which breaks the 50% efficiency barrier for resonate RQ>transformers. I believe three coil designs are possible that RQ>are as high as 95% efficient. ...Sure seems like that would have an effective use in radio transmitters. Ever hear of anyone doing it there? They do work to achieve the highest energy transfer, but to my experience, only with a single primary and secondary.... (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-23-94 18:53 From: Richard Quick To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Discussing low impedance grounds in RF work, xmitters and Tesla coils. TS> From this thread, I'm getting an impression that TS> broadcasters do a little more in the way of operating TS> impedance calculations and measurements, and projected TS> ground related base losses, than folks who stare in awe at TS> man made lightning. Must we be forever in disagreement Terry? Earth ground was first applied to a tuned circuit by the man who created synthetic lightning. The same man who invented broadcasting, and a ground based electrical transmission system which requires no wires. How could you say that the followers of the man who first calculated these figures would be ignorant of his work? I will refer you first to Tesla's own writings: Colorado Springs Notes, 1899-1900, Nickola Tesla, Nolit, Beograd, Yugoslavia, 1978, pp12. Tesla writes a list of three major goals for the experimental lab he is constructing in Colorado Springs. Number three on the list: NT> 3. To ascertain the laws of propagation of currents through NT> the earth and the atmosphere. The diagrams, footnotes, and patent references from pp12-18 alone would be sufficient to convince you the error of your implication. If that is not enough, then I would refer you to the pp36-37 entries for mid-month, June 15-17, 1899. Tesla proceeds to construct a system ground for the oscillator, followed by electrical measurement of both the system ground and the water pipe main supplying the lab. In later work all of the major earth resonate frequencies were plotted with amazing accuracy. The O'scope had to wait years to be invented. In the 1950's Schumann, Bremmer, Budden, Wait, Galejs and other authors verified all of Tesla's "ground" work step by step. See: > Terrestrial Propagation of Long Electromagnetic Waves J. Galeys, New York, Pergamon Press, 1972 DK> alley" and have repeatedly had to try to teach the lesson DK> about the need for low-reactance paths to earth there -- TS> "open land" ground electrodes, rods, screens, bonded TS> radials, etc. I knew we would agree somewhere. I have been stating this here for a year now. TS> If Richard, or anyone cares to comment. What have Tesla TS> experimenters used for ground references? Me not comment? Well I can't speak for everone, but I have listed references above that you would obviously find informative. TS> For those larger coils, I would suspect an array of radials TS> using a few miles of #10 soft drawn Cu, with Erico TS> welded mesh for about 50' in the center, bonded with 4" TS> strap, might be adequate in most places. Add a couple of TS> 30' chemical grounding electrodes in poor soil areas. Does TS> anyone bother in high voltage experiments? I ground my stuff to a buried hydraulic lift. The lift assembly consists of a large buried oil tank, air tank, supply and control plumbing, and the actual steel piston assembly. Run from this ground point (which is all metal spread out over 225 square feet) are two 1" ground straps; one strap runs to connect buried decorative pond (1500 gallon galvinized steel tank), the second runs to a 50' length of 14" wide aluminum flashing submerged in a nearby creek bed. All coil connections to this ground are 15' feet or less for the high powered stuff. I use the equivalent of a 2-1/2" grounding strap from the base of the coil, and the safety gap center post, to the lift control plumbing (both copper and galvinized steel pipe) where it enters the ground. While the grounding system you document would be ideal, mine functions. I do have some idea of what I am doing. I have also done extensive experimentation on coil systems and their grounding requirements. I have followed Tesla's footsteps carefully in many respects. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 16:54 From: Richard Quick To: Roy J. Tellason Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Talking about coil construction... RQ> Get some rigid Plexi, Lexan, or polystyrene pipe/tubing with RQ> a thin wall. RJT> They used a cardboard tube for this, a readily available RJT> item, PVC thin wall plastic "drain" pipe that has been sanded and sealed is generally better than cardboard. RJT> but I'm sure that a lot of the other materials you mention RJT> weren't around in those days. No modern materials were not around, but this does not mean they should not be used. Older coils were plagued with low efficiency and unreliable operation. Many "classic" coils and projects of this nature were full of errors and misconceptions. With modern materials (and designs and schematics that utilize them) at my fingertips I would never look back. RQ> Wind the wire on the coil form. RJT> Is there any easy way to do this? :-) I set up a spindle through the center of the coil form, and roll the form with one hand while feeding wire with other. RJT> That article referred to wooden disks in each end of the RJT> form,..., RQ> I cap the top and bottom of the coil form with disks of RQ> plexiglass bedded in epoxy. RJT> What do you mean "bedded in epoxy"? I mean smear a thick enough bead of epoxy on the cap and the end of the coil form so that the epoxy is forced out when the parts are fitted. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-26-94 16:47 From: Richard Quick To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ ... Still talking Tesla Coils...and inductive coupling. RQ> Yes. A Tesla coil is a resonate transformer. The RQ> "transformer"part means that the system involves energy RQ> exchange by induction. But it is not simply producing a RQ> "maximum induction field", but of producing a field of RQ> proper intensity and shape around a resonate inductive RQ> structure (coil). DK> ...OK, that sounds like there is concern for somehow DK> "shaping" the induction field around a core, rather than DK> merely letting it assume some random proportions, and DK> attempting to couple to it. Or am I zooming off on a DK> tangent? No your shooting dead bullseyes. Field shaping is done primarily by altering the coil geometries. Both primary and secondary coils are juggled until good inductive coupling is secured. The form- ation of a small compact field; even in intensity and sweeping the secondary winding from the bottom turn to the top; usually allows the most efficient transfer of energy between two coils. ... Then talking about... DK> ... the first "radio" people.. RQ>Bahh, Marconi worked for Tesla for nearly a year, before RQ>1891, and stole a lot of technique, not to mention nine key RQ>patents. I am adverse to crediting thieves. DK> ...Now, THAT's interesting to me! So Marconi hung around DK> Tesla, eh? All the histories I've read seem to make no DK> mention of any connection between them. DK>.I *must* get into a Tesla history book one of these days! How about US legal history. The United States Supreme Court overturned Marconi & Co. radio patents in 1943 after testimony and US Patent Office records showed clear priorities. It was proven that Marconi had had access to Tesla's early work and then went on to commercialization with that information. ... talking about grounds as a... DK> ...low-reactance interface to earth. RQ>Tesla was the first to apply ground to a tuned circuit... DK> balanced and floating above ground, then Marconi DK> tying "radio" to ground. Certainly makes sense that Tesla DK> conceived of that change to use the earth for one side of DK> the circuit... DK> repeatedly try to teach the lesson about Alley> the need for low-reactance paths to earth-- RQ>... it seems no ground used for lightning can be too heavy. DK> ... yuh got that right, Pilgrim. DK> concept that the earth does not have unlimited ability DK> to conduct electricity away from a point contact. Oh, DK> electric power engineers know this, but the general public.. What about earth resonate (electrically conducted) frequencies? ... talking about Tesla's extra coil... RQ>The third coil is not inductively coupled to the primary/ RQ>secondary... uncoupled resonator which is base fed RQ>by transmission line.... is allowed to resonate freely, RQ>unrestricted by the inductive coupling between primary and RQ>secondary... I believe three coil designs are possible that RQ>are as high as 95% efficient. DK> ...Sure seems like that would have an effective use in radio DK> transmitters. Ever hear of anyone doing it there? They do DK> work to achieve the highest energy transfer, but to my DK> experience, only with a single primary and secondary.... You would have to talk to a radio engineer, but the principal of resonance was discovered by Tesla. Tesla believed that large resonate transformers offered the key to worldwide xmission of commercial scale electrical power without wires. If you electrically examine the system output, the secondary (or "driver") coil in the three coil magnifier is simply the secondary on a resonate transformer. The extra coil and earth (the top and bottom connections to the secondary driver coil) are acting as end resonators. Tesla to his patent attorneys clearly stated he had discovered, and operated his equipment modulated to, earth resonate frequencies below 30,000 Hz. Looking at the oscillator as a whole, the current flow from the air terminal was small. Tesla operated at very high voltage, but retarded spark breakout when working with CW xmitters. The system is very easily converted to spark production, as witnessed by the publicity spark photos Tesla took of the Colorado Springs Machine. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 23:10 From: Don Kimberlin To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS> DK> ...My own background in high-powered radio (and Terry TS> DK> Smith's, TS>Nah... I've never played with the stuff over 60 KW. ...That ought to be big enough to impress a CB-er, I'd say... DK> btw) have taught us both about the important of a low- DK> reactance interface to earth. I grew up down in Florida's DK> "lightning alley" TS>From this thread, I'm getting an impression that broadcasters TS>do a little more in the way of operating impedance calc- TS> ulations and measurements, and projected ground related base TS>losses, than folks who stare in awe at man made lightning. On TS>a broadcast tower, with a 30 ohm self impedance, but a 10 ohm TS>operating impedance in an array, a resistance to earth (half TS>the radiator, as well as the coupling plane) of 3 ohms, when 1 TS>ohm is practical, makes a big difference. ...As my post indicated, it seems a very small proportion of the population has any notion that the earth is not an unlimited and quite good, uniform conductor. Conversely, we sometimes seem those who get badly hurt and wonder why when they disconnect the electric power grounding wire from the stake outside in order to paint their house... TS quoting Don Kimberlin DK> I have repeatedly had to try to teach the lesson about the DK> need for low-reactance paths to earth there -- seen people DK> lose literally millions of dollars worth of electronics and DK> electrical hardware, plus unmeasurable amounts of business DK> production for trying to ignore it in that part of the DK> country. TS>Have you ever seen anyone explode a concrete building floor TS>slab? That's one I've only heard of, where someone had the TS>brilliant idea of using reinforcing mesh in the slab as a TS>cheap alternative to normal "open land" ground electrodes, TS>rods, screens, bonded radials, etc. ...Seen it happen in Florida when insufficient attention is paid to bonding the rebars in the poured floors, but then tying parts of them to the RF ground screen. You have to bond those puppies all around when you're going to get the huge ground potential rise from hits on a tower 50 feet away. I try to get people to envision a massive electrical wave radiating outward from the discharge point, much like being in a canoe and tossing a huge boulder overboard. The canoeist usually gets swamped... TS>Up these parts, we get winter. Down your way, I guess you're TS>more likely to see a glass encapsulated (and therefore TS>insulated) ground rod, from lightning melting the quartz sand TS>around the rod? ...Happens occasionally, but the larger hazard is a buildup of non-conductive salts on the rod, then when there is a hit, the rod conducts little or nothing, so the lightning goes elsewhere and wreaks havoc. If you can imagine it, one actually needs to pull ground rods and "maintain" them in many locations. Some recommend doing that every two years, but most don't do anything till they have a problem, and get away with 10 years or more... TS>If Richard, or anyone cares to comment, what have Tesla TS>experimenters used for ground references? For those larger TS>coils, I would suspect an array of radials using a few miles TS>of #10 soft drawn Cu, with Erico welded mesh for about 50' in TS>the center, bonded with 4" strap, might be adequate in most TS>places. Add a couple of 30' chemical grounding electrodes in TS>poor soil areas. Does anyone bother in high voltage TS>experiments? ...Why sure, they all put in the FCC-standard 120 radials of 1/4 wavelength each at 60 Hertz! (heheheee...nobody has that kind of money!) Concord,N.C. (704)792-9241 (1:379/37) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-27-94 21:22 From: Richard Quick To: Don Kimberlin Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Sez Don Kimberlin to Richard Quick, about extra coils <=- DK> ...Sure seems like that would have an effective use in radio DK> transmitters. Ever hear of anyone doing it there? They do DK> work to achieve the highest energy transfer, but to my DK> experience, only with a single primary and secondary.... I should point out that Tesla fully intended his system to xmit communications AND electric power. He had motor/alternator sets which converted low frequency current (line power) into high frequency multiphase CW current. When tuned and transmitting, the extra coil was connected to the base of a large antenna. The power supplies were patented by 1893, all of the oscillator/ antenna circuits (with explicit earth ground requirements) patents were in place by 1897. I should stop here and state that the US patent office repeatedly turned Tesla down for patents on wireless power transmission system.... A patent office official was then given an explaination and demonstration of the system by Tesla in person, and a patent was immediately granted. He was operating the "Magnifing Transmitter" at 250 KVA by 1900. Tesla also had a custom Westinghouse high voltage transformer at Colorado Springs, and rotary spark gaps for disruptive operation. The extra coil was disconnected from the antenna, air gaps were placed in the primary, and the system was retuned for spark. The famous spark photos were taken mainly for publicity, when the coil was xmitting there was noting to see. But the spark photos do show his tuning, his power levels, and his understanding of harmonics. Sparks were not on the list of priority researches to be investigated. Tesla also used the coils as tuned antennas\receivers. Using coherers, relays, bulbs, etc., as indicators, Tesla was able to detect far off lightning strikes (300 miles), and it appears, pulsars, with his 45 foot diameter "radio telescope" setup. None of this work, or any of the patents issued to Tesla, can be dismissed trivially. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 14:56 From: Terry Smith To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ TS> Back to the technology, do you know enough about the TS> time/frequency/power/conducted-induced-radiated signal TS> relationships to answer the questions previously on the TS> table, or to compare them for various coil designs, with and TS> without the third tuning coil? RQ> Absolutely, where did you think I get my numbers? Make them RQ> up? Too many people here have see how I document my work. RQ> You are I've noticed you've taken pains to document several aspects of your work well, and that made me curious if you've tested other parameters which have either not been mentioned, or which I've failed to notice discussed here. In arcing resonant circuits, how closely does output track input? (Input, I assume, is safer and easier to monitor directly?) Outside of commercial environments, few people are equipped to monitor induced and radiated fields quanitatively. I was hoping you'd know of such studies by someone, if not equipped to measure that aspect of large coil operation yourself. (Impress me... Are you?) As Don pointed out, your endeavors have great similarities, as well as major differences, to systems on which he or I have worked. Even in commercial situations, there are frequently pieces of test equipment which would be useful, but not in the budget. TS> Obviously it's a time/energy relationship which allows TS> describing a single coil as 10 KVA, and also as 2 megawatts TS> peak output. RQ> Very good. Go to the head of the class. Sorry for any confusion. Power levels have been mentioned at times out of context, in a thread lengthy enough so that it takes some sorting to keep track of peak versus average aspects of the discussion. RADAR would be the obvious model for time/energy relationship spec comparisons, but controlled to rather precise tolerances compared to what I'd guess you see in arcs? TS> As to the 6.78 MHz or other ISM frequencies, I strongly TS> suspect that imitation lightning is inherently too wideband RQ> ^^^^^^^ TS> to possibly be confined to such allocated legal spectrum. RQ> BTW, where did you come up with this frequency??? 47CFR18.301 (FCC ISM Regs, where unlicensed signal strengths are conditionally unlimitted) Doesn't everyone have a copy on the bookshelf by their computer? That's the lowest of the available frequencies of that type, and one with a usable harmonic also. If emmisions could be confined to a narrow bandwidth, the need to suppress signal transmission could be made moot. I know you've discussed resonant versus "brute force" circuits. On the other hand, arcing tends to involve a wide frequency domain, due to variable equivalent waveforms during rapid rise and fall. I would presume the former could not be used to control bandwidth due to the latter. Do your experiments confirm this, or are there any interesting tricks by which it's possible to regulate the effective frequency of an arc rather narrowly? TS> Quite frankly, I'm amazed that megawatt surges haven't TS> caused neighbors problems. RQ> I am sorry to disappoint you. I have expended time and RQ> effort to ensure I am not a causing a problem. I've noticed in other posts discussion of coils large enough to need a 60x80x50 foot bonded steel structure to house but suppress the output of some coils. This would be beyond what's available to hobbiests without unusual means, and I have noticed emphasis at times on avoiding the cost of commercial vacuum or G type mica capacitors. If you've conducted the operations described here, and suppressed both RF complaints and regulatory violations, I'm impressed, rather than disappointed. An old barn, or the back yard on a nice weekend afternoon, would be more in line with what I'd expect of a test site for anyone other than a career technologist, like Tesla. What special steps have you taken to avoid RFI problems with neighbors? Is there something I'm overlooking about the nature of the output of these coils which makes the radiated output couple so inefficiently to the earth that RFI is less severe than from other forms of high power arcs? BTW, the Origin line is one of several I've been rotating since well before this thread started. Terry ! Origin: Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-24-94 22:21 From: Brian Thurston To: Richard Quick Subj: TESLA ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Hi Richard: A very concise and succinct statement of the events concerning Tesla and his AC transmission systems. My only additional fact is that Tesla died pennyless in Canada still trying to develop his wireless energy transmission system into a commercial product. Regards, Brian. White Rock, BC, Canada (1:153/915) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-26-94 09:30 From: Michaelj Scott To: Richard Quick Subj: TESLA COILS, VIDEO ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ MJS responding on 26Jun1994 to RQ's 14Jun1994: >Mike, >Thanks for the nice letter. Your video tape was posted this >morning,you should receive it shortly after you get this post. Both probably arrived the same time, but I'm two weeks behind on reading. I download a couple of times per week for the echoes that interest me, but I only get to read them on Sunday. >I included a disk with many related text files. It should make >for some interesting reading, as the archived material goes back >over six months. I've only had time to watch it once, late at night with my wife. She was much more interested in the old cars than in "that giant sparking thing". Richard, the video does a great job of getting the thrill of seeing a monster Tesla coil venting angrily at the world. The sound effects were something of a surprise. We loved watching the experiments progress; the raising of coil, the cleaning of the garage, moving the whole apparatus outside. All of this over several days (weeks?) lets us get a sense of the enormity of the project and the attention to detail. I think I've been following this echo for about 6 months, maybe a little longer. I haven't had time to look at the floppy, but I'll get to it soon. As I mentioned, I'll likely not be building a Tesla coil, but the pictures to go along with this lively reading are a must have for anyone who has been following the Tesla coil threads. >If you have any problems, questions, comments, corrections, >etc., please post me. Do let me know that you have received your >video, and let us know what you think. As a mere electronic engineer, I don't think that I'm qualified to offer any corrections to the high powered lash-ups that you have concocted. The only time I had to deal much with coils or transformers, was once with a "magnetic amplifier" that controlled a motor to the vanes and thereby regulated the temperature in a jet engine. It used diodes and resistors to saturate transformer cores and hence used current from one circuit to control much larger current in another without transistors or tubes. It was very reliable, nearly vibration proof, operated from 80 below to 300 above zero, and would work submerged in water. No sparking or arcing though. I look forward to sharing this with my co-workers. We need to get a TV and VCR up to work, since I do not want this tape to get "borrowed" like other lost tapes. The early part of the tape suffers a little from an unsteady hand but does get the point across nicely. Some of the close-ups weren't. I was concerned that you or an onlooker might be hurt by an errant spark. Sparks as big around as a beer can, leaving large black marks on your driveway seems equivalent to playing outside in a Texas lightning storm. Thanks for the wonderful video tape. It's the best thing I've seen on the TV in quite a while, although my wife would debate that opinion. You will likely get some response from some other Michael Scott claiming that he never heard of you. There are more than 10 of me and my clones running around here in the Sacramento area. I've appended a "J" to my Christian name in an effort to distinguish myself from the other imposters. Regards, Mike in Folsom, Calif. (916) 448-2483 (1:203/52) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06-28-94 13:41 From: Dave Halliday To: Richard Quick Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Hi Richard Just dropping a note to let you know that I am still incredibly busy at the store but I plan to have the coil up and running in about a month or so. I finally broke down and hired another full-time person so I can go back to "normal" 8-10 hour days... sheesh... Also, I was wondering about the current regulation going into the pole pig - you are using an arc welder. I have several baseboard heaters and I was thinking of paralleling a couple of those - lossy but hey! The work on the controller is going well - I have not hooked it up to the variacs yet - it's still at the store but it works well. I had done some other projects using that CPU so I still had some development boards left. (206) 528-1941 (1:343/210)