ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-05-93 12:54 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ I get some good results, not many people can hold a candle to it. Need to move into a warehouse with some headroom and more power. A dedicated substation would be nice... RQ DT> Where are you running this thing now, out of curiosity? DT> Don't the neighbors complain about the RFI? DT> Do you have any pictures or .GIF files of this unit in DT> action? I run either in the garage for low power tests, or set up outside in the back driveway for the real high powered stuff. I have had no RFI complaints, but have had complaints about the noise: the spark gaps sound much like an unmuffled chainsaw run flat out, wide open. I made peace, and am allowed to fire up until 10 P.M. with a days notice. But no more 2-3 A.M. testing... > I have used forced air cooling (ozone city) with good results > up to about 5 KVA. RQ DT> Have you tried cooling the air before it is blown into the DT> spark gap? You could run the air (I'm assuming that your DT> using an air compressor) through a coil of copper tubing in DT> your ice bath. The best part is when the air expands as it DT> is blown into the gap, it will cool further. (basic physics DT> of gasses type stuff) I cool using forced air from a 220V industrial shop vac motor in my old set of gaps, the new gaps are quenched by air blast from a 3.5 HP air compressor. The problem is the CFM of air flow required is so large that I don't think pre-cooling is practical. It would require another design modification. The expanding air alone works pretty well. The real advantage to high speed forced air is that it not only cools, but it physically disrupts the high voltage arc, assisting the rotary in making the break. Your idea for a forced air cooled rotary gap was excellent. The only problem I see is in engineering the units to specs close enough to get excellent performance and safety. My rotors are dynamically balanced to 5000 RPM, and break rates need to be 450 BPS or better for good operation. In designing a rotating break I try to keep the mass as low as possible on the rim: when they come apart they resemble an explosion, with lots of hot shrapnel and plenty of arcs and sparks! > The research goes into several directions...Anybody know how > to get lightning to excite a gas laser tube? RQ This was misunderstood by several people. Specifically what I was wondering about was the possibility of using the oscillator output (which is similar to lightning) to excite a monopolar (one wire input) gas laser tube. DT> Do you know what the mix is in a standard NeHe laser tube? No. I am not an expert on lasers. But I am more than willing to learn. I am open to input from anybody with experience. RQ> ... And if all else fails... Put another megavolt through RQ> it. DT> With your equipment, it sounds like you actually could... Absolutely, positively. Though I can't figure out how to make a RF voltmeter that would not be utterly consumed by the output of my machines. My guess is between 3 - 5 million volts output with the setup we have been discussing. As for proof. Yes, I can supply proof. I have some still photos taken at about 3600 watts which are very impressive. But as my work progressed I switched over to recording the experiments on video tape so I can analyze the tests in the safety and comfort of my living room. If anybody writes me I will happily provide a two hour video tape in exchange for: One blank (high quality) VHS tape, a postage pre-paid return mailer, $10.00 to pay for my time and effort in seeing that you get a high quality, two hour, recording of my work. Note this offer is not made on my behalf to make any money, and I am not responsible for anybody's safety should they decide to replicate any of the experiments I perform. I will send a glossy print for $1.00 and a SASE. Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale, Missouri, 63122, USA ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-09-93 16:29 From: Richard Quick To: Guy Daugherty Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ GD> I'd say if they're working that well for you, they're hardly GD> junk. Is there, uh, any point to this stuff, or just GD> blasting electrons across the ether? Yes, there is a purpose. Actually more than a few. High power particle accelerators is one. The typical linear accelerator of the 30's and 40's were RF powered. They abandoned the coils as they were not sufficiently frequency stable, and the output was damped as opposed to continuous wave. But, a book was published last year: NICKOLA TESLA ON HIS WORK WITH ALTERNATING CURRENTS AND THEIR APPLICATION TO WIRELESS TELEGRAPHY, TELEPHONY, AND TRANSMISSION OF POWER. Leland Anderson, Sun Publishing, available through 21st Century Books, P.O. Box 2001, Breckenridge, CO. 80424. This work is the result of research into the files of several law firms dating back to around 1915. Tesla was called to give depositions for three days to prepare for patent trials against the Marconi Company. Tesla clearly documented priority in frequency stabilized continuous wave signal production and radio signal transmission (and reception) on multiplexed circuits as early as 1891. All of Marconi's patents pertaining to radio were overturned by the U.S. Supreme Court in 1942 or 1943. The key to this is that Tesla's work in this area was extremely advanced, and most of it has yet to be applied to high powered accelerator work. His systems of continuous wave RF current production with very high potentials is easily adapted to small, high powered, linear particle accelerators. The peak powers of his Colorado Springs machine (built, tested, and documented in 1899) exceeds all but the largest accelerators in existence today. By the way, the Tesla system is continuous, and the modern systems are pulsed. The misunderstanding is damped vs. undamped wave production. The machine is capable of both, though the famous photos were taken when the machine was set up to produce damped (disruptive) waves. I don't think anybody really understood what Tesla was doing, certainly he never clearly explained it until I read the work above. In addition to this, a moderately sized machine should be capable of doing research into power transmission through earth resonate ground currents at frequencies under 30 khz (see document above). Later Tesla realized the particle accelerator potential of the machine and designed a power head for a particle beam weapon using the magnifier circuit as the signal generator. Lasers were not invented yet when Tesla died, but I believe a low impedance coil system can supply enormous peak powers to gas laser tubes. The Maser is a derivative of this line of investigation, though the frequencies of operation are much higher than can be supplied from a coil system, the idea is exactly the same. Use a tuned gas laser tube as a cavity resonator excited by the RF output of the coil system. Then there is ball lightning research... ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ- Date: 10-09-93 22:35 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >a two hour video tape in exchange for: One blank (high >quality) VHS tape, a postage pre-paid return mailer, $10.00 to >pay for my time and effort in seeing that you get a high >quality, two hour, recording of my work. Note this offer is not >made on my behalf to make any money, and I am not responsible >for anybody's safety should they decide to replicate any of the >experiments I perform. I will send a glossy print for $1.00 and >a SASE. RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, >Glendale, Missouri, 63122, USA Two comments: 1) - What IS your monthly electrical bill 2) - The $10 is in the mail Monday have been a wee fan of Tesla for a looong time - talking with some people now about maybe building a BIG one out in Seattle - have done a few small ones. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-26-93 11:57 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >a two hour video tape in exchange for: One blank (high >quality) VHS tape, a postage pre-paid return mailer, $10.00 to >pay for my time and effort in seeing that you get a high >quality, two hour, recording of my work. Note this offer is >not made on my behalf to make any money, and I am not >responsible for anybody's safety should they decide to >replicate any of the experiments I perform. I will send a >glossy print for $1.00 and a SASE. RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, >Glendale, Missouri, 63122, USA DH> Two comments: DH> 1) - What IS your monthly electrical bill I'd rather not go into electric bills, let's just say it's going to get worse... DH> 2) - The $10 is in the mail Monday I will be sure you get lots of Arcs & Sparks for your hard earned money. I will get the tape out the following mail day. It would help to know if you are more interested in seeing spark or technique. DH> have been a wee fan of Tesla for a looong time - talking DH> with some people now about maybe building a BIG one out in DH> Seattle - have done a few small ones. Big coils are a challenge. But I really think (and experiments prove) that the Magnifier System is more efficient as you scale up. Large 1/4 wave Tesla coils are not nearly as efficient. Send me a post and let me know what you think of the video. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-10-93 16:33 From: Richard Quick To: David Bearrow Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DB> How did you go about winding your coil? What are the specs? DB> And how much did it cost? The first step in winding a coil is to select a coil form. The coil form should be a low loss material (we are talking RF losses) like polyethylene, polystyrene, or polypropylene, Lexan, or Plexiglas (acrylic): but a common material is PVC, which is high loss. Thin wall tubing is best regardless of material. Ratios of coil height to width are important. Small coils work best with aspect ratios (height to width) around 5:1 - 4:1, larger coils (over 8" diam.) have aspect ratios around 3:1. Now we are talking about the actual winding length here, so allow an extra inch or so of coil form on each end. Determine the length required and cut the ends square. The form must be sanded smooth of surface imperfections, dried thoroughly, and if PVC is used, it must be sealed. A good sealer is polyurethane, another is two part epoxy paint. By sealing the surface of the PVC before you wind on wire you can negate the excessive losses in PVC plastic coil forms. If necessary the coil form may be sanded after the sealer had dried. The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range. I plug the ends of the coil form and run a dowel through a center hole so that it will spin. I set up the wire spool on one end of a pair of sawhorses, and the coil form on the other end. I wind the wire on by hand, making sure the windings are tight, smooth, and even. I use a dab of hot glue or tape to hold the first turns in place, and make sure to leave a tail of wire at either end. Once the coil is wound, it is sealed to prevent corona leakage and breakdown. I use the same sealers mentioned above. Coats of sealer are applied until there are no ridges and valleys in the wire. In other words the coats must build up until the wire is completely imbedded in sealer. The wound, sealed, coil is capped at both ends with plexiglas plates glued down with epoxy. I cut circles out of plexi sheet that is about the same thickness as the coil form. I rough up the surface around the edges to give the epoxy a bite. One small hole may be drilled into the bottom end plate to allow the air pressure to equalize, but under no circumstances should any other holes be drilled. The wire is never allowed inside the form. I have numerous coils, my largest coil has specs as follows: 10.5" O.D. thin wall PVC flume duct, the coil form is 34" high. The coil is wound with #21 magnet wire, 1024 turns, actual winding length is 32", aspect ratio 3.05:1. The coil is sealed with eight coats of polyurethane on top of the wire and five coats under the wire so that the wire is not in contact with the PVC but is suspended in sealer. Coils take time more than anything to construct. I suppose the material cost for my 10" coil is around $60.00. Smaller coils are cheaper of course. What can be expensive is putting together the rest of the oscillator components. Things like HV pulse capacitors, xfrmrs, and power controllers like variacs. Beginners can usually start with a few old neon sign xfrmrs, make some caps (homemade salt water caps are very cheap) or buy some used, and fire a small coil for under $150.00 from start to finish. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-13-93 00:46 From: Richard Quick To: David Bearrow Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >> The coil should be wound with good quality magnet wire. I use >> double Formvar enamel coated magnet wire. Magnet wire gives >> you maximum inductance. A coil should have over 900 turns, >> but not too much over 1000 turns. There is a little leeway >> here. Select a gauge of wire which will allow the aspect >> ratio and number of turns to fall within this range. DB> Did you calculate this so that the capacitive reactance DB> equals the inductive reactance? I understood that's what was DB> so interesting about Tesla's coils. No. The balancing act that you are referring to occurs in the primary tank circuit. High voltage pulse discharging capacitance (capacitive reactance) is made to balance off the heavy primary coil (inductive reactance). The primary coil is made to very low resistance; like HEAVY cable, strap, or soft copper water pipe. The inductive reactance is "canceled" by the capacitive reactance, and a very low resistance "tank" is formed where heavy currents can oscillate with low loss. In order to excite the tank circuit, high voltage feed lines are brought in to charge the capacitors. Voltage rise in the capacitors (as they charge) breaks down the main system spark gap, and bang, the tank fires. Currents of hundreds of amps, with voltages in the thousands of volts, ring through the Tesla Tank Circuit. The energy delivered can easily reach peak powers in the megawatt range. Since the main system spark gap fires hundreds of times per second, these high peak powers are, for most practical purposes, continuous. This primary circuit energy is transmitted through inductive coupling to the Tesla Secondary. The secondary coil that I described in the quoted post is NOT a balanced coil. On the contrary, this coil is pushing the extreme of several design limits in the quest for more efficient power processing. The secondary coil, wound as I instructed, results in a very high inductance coil; but it has a significant internal capacitance and resistance due to the closeness of the windings, the length of the wire, and the number of turns. The high inductance makes the secondary effective. The higher the inductance, the more energy can be absorbed from the primary tank circuit. Resistance and internal capacitance limit the Tesla secondary for obvious reasons. Current, especially RF current, reacts poorly to resistance, which gets worse in small diameter wire. Internal Capacitance in a coil also reduces throughput, as the capacitance in the turns of wire slow the current peak. Designing a potent Tesla secondary balances the maximum inductance (a positive factor) against the resistance and internal capacitance (negative factors). It takes into account the need for "critical coupling" between the primary and secondary (for good energy transfer), resistance of the wire, internal capacitance between turns, and the breakdown voltages of the construction. The design given is well researched and proven. > BUT THE COIL IS UNBALANCED!!! YOU SAID SO ABOVE!!! Yes, it is VERY unbalanced. Yes, the Tesla circuit depends on balance for maximum efficiency. The high inductance of the secondary is balanced by the addition of a large (even huge) top capacitance. Donut shaped dischargers, called toroids, are used as a large capacitive air terminal. This air terminal capacitance "unloads" the secondary, and allows for current flow through the high inductance coil. The secondary coil, as I instructed, will not function well without an effective discharger; a capacitive reactance to balance it. Without it the coil will not survive much input energy and will self destruct. We have just pushed the limits with modern plastics in 1/4 wave Tesla oscillators. Back to the primary; the circuit is tuned. By changing the location of the tank circuit "tap" connection to the primary, the frequency of the circuit is altered. The more turns, the lower the frequency. The secondary coil acts like an antenna. This wire when excited by the primary, vibrates electrically, and produces a quarter wave signal. The frequency is primarily a function of wire length and the capacity of the discharger. The primary and secondary are both adjusted to operate at the same frequency. So there is a lot of balancing going on. By the way, I make my toroids out of 4-6" ridged flexible black polypropylene drain pipe. I make a circle and mount some cardboard or thin masonite in the center, then cover the thing with aluminum plumbers tape, and foil glued with adhesive spray. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-12-93 18:29 From: Bud Davis To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >In a message of , Richard Quick (1:100/4) writes: > A twenty-two megawatt continuous fire gas laser... BD> I just picked up this thread a week ago, your recent postings BD> are saved to a file...This is very interesting! MF> 22 MW is your input, with typical gas laser efficiency you'd MF> be lucky to squeek a (one) measly MegaWatt out. Just enough MF> to cut through armor at a few inches per second, or mabey a MF> foot of steel. Don't know about lunar soil. Some gasses MF> don't scale well to high powers, CO2 would probably be MF> the best candidate. >I kind of thought CO2 was the way to go, but I was not sure. I >have not had much experience with high powered gas lasers, >though I did build a ruby rod laser in high school powered by a >xenon flash tube. I can't find the rod anywhere now... BD>CO2 is a good choice for high power. I'm not sure which BD>transition level for CO2 is used for lasing but I could find BD>out. >I have a feeling that with a properly designed system though, >the efficiencies could get considerably greater. My assumption >is based on some experiments which show that RF excites gases >much more easily than high voltage, high currents, or both. >Tesla went on and on about the advantages of using RF when >energizing gasses. BD> A Soviet researcher named Kapitza developed RF devices with BD> plasma temperatures high enough to fuse hydrogen! They used a BD> cylindrical resonant chamber driven by a room full of tuned BD> circuits, the high temperature was observed in a corona BD> discharge along the axis...I guess it went on the back burner BD> along with the tokomak. BD> Hmm...stick a CO2 filled tube in a properly sized RF BD> resonator... a few mirrors, heat sinks... BD> I wish I had your original post. :-((508)544-2402 (1:321/154) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-14-93 10:57 From: Richard Quick To: Bud Davis Subj: Re: 10kva Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BD> CO2 is a good choice for high power. I'm not sure which BD> transition level for CO2 is used for lasing but I could find BD> out. RQ> Please check into it and let us know what turns up. >I have a feeling that with a properly designed system though, >the efficiencies could get considerably greater. My assumption >is based on some experiments which show that RF excites gases >much more easily than high voltage, high currents, or both. >Tesla went on and on about the advantages of using RF when >energizing gasses. BD> A Soviet researcher named Kapitza developed RF devices with BD> plasma temperatures high enough to fuse hydrogen! They used BD> a cylindrical resonant chamber driven by a room full of BD> tuned circuits, the high temperature was observed in a BD> corona discharge along the axis...I guess it went on the BD> back burner along with the tokomak. I really feel that there is a lot of uncovered work in areas such as this. The publication I referred to last week (A transcription of a legal deposition Tesla gave in 1916, over a period of three days) is only a year in print. Using some of the ideas that Tesla presented in this deposition in work such this has not been done. BD> Hmm...stick a CO2 filled tube in a properly sized RF BD> resonator... a few mirrors, heat sinks... Yup, very close to my thoughts. Tesla states that low pressure gas, being highly conductive to RF, can be used as the actual resonator. So take a properly sized resonator, fill it with CO2, a few mirrors, heat sinks... The actual resonator can be the laser tube, and losses can really be cut down. This is exactly how a MASER works, but needs to be scaled up for low frequency work. I have been wondering about the addition of a short coil to the resonate chamber to bring the frequency down, thereby keeping the size of the resonate chamber under control. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-14-93 16:53 From: Richard Quick To: Bud Davis Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ P.S. I would also be very interested in the source material for the information you relayed on the Russian RF work. Experiments of this nature (using RF inputs to excite tuned resonators) is exactly along the line that my future work will be heading. I don't know how much of this thread you were able to pick up in a week (I have seen a lot of posts indicating new boards getting this echo in the past week) but I am currently running and improving very high powered equipment. Experiments of this nature are not at all beyond my means. I have all of the power controller circuits, the capacitors, and the HV xfrmrs. I am developing a new liquid cooled, air blast gap to run in series with my rotary, and I have plenty of coils, both primaries and secondaries. I have constructed and fired small Tesla Magnifiers in the 2.5 KVA power range, and feel (like Tesla did) that the magnifier circuit is a clear and away breakthrough in RF power processing efficiency. A properly designed and constructed Tesla Magnifier system easily achieves 70% efficiency, and can be brought up to over 90% efficient in larger systems. They will produce and process damped and undamped (continuous wave) signals depending on the setup and power supply. The currents and voltages this circuit will handle are nothing short of mind boggling. The Magnifier is designed specifically to drive a 1/4 wave resonator, whether it be helical (coil), coaxial, or cavity, makes no difference. I doubt that the Russian was using a large magnifier to drive the resonator in the experiment you mentioned. James & Kenneth Corum (PhDs) did not publish the mathematical treatise of the Tesla Magnifier until just a few years ago, and until the treatise was published, nobody was able to get the free resonator to function properly as part of the lumped, tuned circuit. These problems have been worked on and resolved by very few people since. I can count myself as one of the half dozen or so who have publicly documented success. My best guess is that the Russian was using a large tube powered RF signal generator to drive a coaxial resonator. I think that if the experiment were redesigned, it could be done much cheaper, at much higher powers and efficiencies, with a Tesla Magnifier driver circuit. Tesla went on and on about this stuff too, nobody listened then, and few listen today; hell, people ask me all the time why I chase such "impracticalities". They don't understand that Tesla was so far ahead of his time that we still haven't caught up! My guess is that we stand today where Tesla stood in 1898, as far as RF power processing efficiencies are concerned. But photos or data from the Russian experiment would be invaluable for any work in this direction. What did he use for a transmission line? How did he introduce the signal into the resonator? From having done a little work with helical resonators to produce large voltages at very high currents, I realize technique is half the battle. Any additional information on this work would be appreciated. As for what you missed, well it can't be as much as what is most likely still to come. Stay tuned!!! And feel free to ask about anything you don't understand. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-16-93 18:39 From: Richard Quick To: Ron Beam Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ >On Oct 10 16:33 93, Richard Quick of 1:100/4 wrote: >Coils take time more than anything to construct. I suppose >the material cost for my 10" coil is around $60.00. Smaller >coils are cheaper of course. What can be expensive is >putting together the rest of the oscillator components. >Things like HV pulse capacitors, xfrmrs, and power >controllers like variacs. Beginners can usually start with a >few old neon sign xfrmrs, make some caps (homemade salt >water caps are very cheap) or buy some used, and fire a >small coil for under $150.00 from start to finish. RQ >Richard, do you know what frequency (if not 60Hz) and voltage >should be used for a coil such as you mentioned? Frequency and voltage entirely depend on the aims of the designer/builder. Since none of these systems are purchased (nearly every component handcrafted) they can be built to nearly any specification desired (within reason). Frequency, input & output voltages, current, and impedance are just some of the variables. The idea with a Tesla coil system is to covert 60 cycle line current into RF with very high efficiencies. My 10" secondary coil has a natural 1/4 wave resonate frequency of 132.5 KHZ. I use a power distribution transformer run backwards (put 240 in and get HV out) to step up my line voltage to ~20,000 volts. This input RMS voltage is converted into RF (say 132.5 KHZ) by the Tesla Tank Circuit. The high frequency conversion is achieved as a property of capacitive discharge through a coil (tuned oscillating circuit). The main system spark gap acts as a high voltage switch which allows the capacitor to charge over a period of time, then discharge nearly instantaneously. Because of the pulse discharge, the RF generated in the tank circuit has much greater peak power than the HV feed line from the step up transformer. The grounded secondary coil receives the EMF from the primary and converts the energy back into electricity (air core RF transformer). Since the secondary coil has a much greater number of windings the voltage is stepped up considerably. > What does the coil do (or look like) when you turn it on? A 1/4 wave Tesla coil generates very long RF sparks that resemble natural lighting in many aspects. These sparks do not need to strike a grounded object but can terminate in air. >What can a person do with such a device once constructed? Does >it have any practical purpose other than to amuse your friends? I first began to build small 1/4 wave (spark generating) Tesla coils for fun. I loved the light show, and so did my friends. As I gained experience in building coils I realized that most of the "plans" were full of inaccuracies. I began to design my own systems to increase efficiency. As my interest and experience grew, I discovered more advanced coil systems that Tesla designed (the Tesla Magnifier) and began initial research into other areas: particle acceleration, lasers, wireless power transmission, and particle beams. I am planning on making a very serious study in these areas in the next few years. Dave Archer is a painter in California who uses a Tesla coil to electrically spread paint. He places his canvas on a grounded plate and directs the Tesla discharge over it. The resulting paintings are regularly featured as space backgrounds and hanging art on Star Trek TNG, Omni Magazine and several other publica- tions, as well as private collections. Tesla coils were also used in the time travel scenes in both Terminator movies, and are re- emerging in the special effects industry because they photograph well and the sparks are more realistic than computer generation or animation. Two years ago a man (I don't have his name handy) was issued a patent for a thermo-couple using a Tesla discharge. Tesla coils were used in the first induction heaters, and were employed medically for the treatment of arthritis and other joint and muscle problems. The same coil could be adjusted to generate sufficient voltage to produce X-Rays, and as such a Tesla coil was a standard medical instrument in Dr's offices in the early 1900s. Nearly all of the first high quality X-Rays were produced with Tesla driven X-Ray tubes until the 1930's. The first self cauterizing "electric scalpels" were electrified with a Tesla coil. A Tesla coil is in your monitor (flyback transformer). Tesla coils were also an important part of the first radio transmitters. My feeling is that the Tesla coil has a major place in modern physics, but has not been fully evaluated. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-16-93 21:30 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ This thread seems to be getting a lot of attention and responses. I will try to give some basics here, and answer a few questions. The modern 1/4 wave Tesla coil (sweet and simple, though there are other configurations) is an oscillator driven, air core resonate transformer. The oscillating tank circuit drives the secondary coil. The tank circuit consists of pulse discharging capacitors, air gap (break) and the primary coil. In my previous post I said the setups are very flexible, so I will focus on specs for the 10KVA coil. The primary coil is wound from a single 100' length of 1/2" soft copper water pipe placed on plexiglas stand off insulators. The inside turn starts at 14" in diameter, and the turns wind outward to form a flat pancake spiral, like the grooves on a phonograph record. The outside turn is 36" diam.. There are a total of 15 turns in this coil, spacing between turns is 1/4". There are many ways to place the gap and capacitance in the tank circuit. I like the "balanced" circuit Tesla developed in Colorado Springs for his monster machine. In the balanced circuit the capacitance is divided into two equal parts and placed on the ends of the primary coil. The gap is placed across the HV feed line feeding the caps. I own two .1 mfd 45 kvac pulse discharging capacitors. These two custom commercial units were purchased to supplement my 14 homemade polyethylene/aluminum flashing/mineral oil units rated at .02 mfd 10 kvac pulse. With the 10 KVA coil I use these two commercial "caps". In the balanced circuit the capacitance is run in series with the primary, so the actual operating capacitance is only .05 mfd.. I connect one cap to the inside turn terminal of the primary. The second cap is connected to a movable "tap" lead which can clip to any location on the heavy primary coil. By moving the tap lead, the primary coil inductance is varied, and the tank circuit frequency can be changed. With one capacitor terminal connected to each end of the primary, I still have two free capacitor terminals. Across these terminals I place the gap, and the HV feed lines. When HV 60 cycle current is fed to the capacitors they charge. As the voltage rises, tension builds in the air gap. When the tension is sufficient, the gap breaks down and the capacitors are discharged rapidly. This spark gap acts as a high voltage switch. When the gap is open, the capacitors charge. When the gap fires, the caps are discharged in a pulse. Because of the voltage and currents involved, the gaps on larger coils employ a rotary break, almost exactly like a large car distributor at high speed. This pulse discharging produces a large current (over 1000a@20kv in my system) from a modest transformer output (.5 amp @ 20kv). The pulse "rings" from capacitor plate, through the coil, to the second capacitor plate; and back again. The frequency of the "ring" (oscillation) depends on the size of the cap, and the inductance (# of turns) in the coil. Since my capacitance is fixed, the coil size (inductance) is varied by moving the tap to a different location. In this fashion the spark gap oscillator is tuned. The parameters of this particular system allows frequencies from ~200 - 57 KHZ. Now the secondary coil (specs in previous post) has a natural frequency of 132.5 KHZ. I load the secondary coil with top capacitance, most commonly a toroid shaped conductive terminal. This lowers the natural frequency of the sec. coil. My best results were obtained using a 40" diam. X 4" thick torpid discharger, lowering the frequency of the coil from 132.5 kHz to 79 kHz. The secondary coil with discharger is placed upright in the center of the primary coil. The secondary coil base wire is ground to a heavy, dedicated, RF ground. The air terminal is of course the other connection. By tuning the frequency of the primary tank circuit to match the frequency of the secondary coil, energy is transferred from primary coil to secondary coil thorough mutual induction. This is much like a common transformer, but at these frequencies an iron core is wasteful. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-16-93 21:54 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ 10KVA Tesla Coil cont. In essence the primary coil is an inductive RF transmitter, and the grounded secondary coil is an inductive RF receiver. The secondary coil receives the energy from the primary and become electrically excited. The coil develops a 1/4 standing wave of the system frequency, hence "1/4 wave" Tesla coil, or "1/4 wave helical resonator" are descriptive terms. What that means is that the potential at the base of the coil (ground) is "zero". The voltage rises up the coil until you reach maximum potential at the top. This is essential to producing good spark. If you look at a sine wave of one complete oscillation you will see half of the wave above the "X" axis, and half of the wave below the "X" axis. The point where the sine wave crosses the "X" axis is ground potential or "zero" voltage. On the "Y" axis you will find the peaks of the sine wave located at the 1/4 points of the wave length. These "Y" axis peaks are the locations of the maximum voltage. The "X" axis crossings ("zero" volts) are the locations of maximum current in the wave. So to come back to lay terms, the base of the excited Tesla secondary is at ground potential, but there is a lot of RF current flow. For the coil to operate, this current must be removed, hence a heavy RF ground is required. The top of the coil is the high voltage end, where the 1/4 wave voltage peak is located. Since the voltage is RF, and the discharge terminal is air insulated, the voltage simply breaks down the air. Large sparks and streamers and corona leave the discharger in a display unequalled by anything else in my experience. The high voltage can be trapped in the system by adding discharger capacitance until the spark will not break out. Energy is constantly fed into the coil from the primary, and the only escape is through radiation or the ground wire. Radiation alone simply cannot remove the energy in the coil, so massive currents are forced into the ground. This forms the basis of Tesla's system for wireless power transmission. Experiments confirming his ideas can be performed with small coils. I took a single 6" Tesla secondary, no primary or tank circuit, just a coil and a discharger; and walked over a quarter mile, to a nearby creek. I grounded the coil by placing 10' of aluminum flashing in the creek water. Back in my basement, an assistant fired a Tesla coil that operated at the same frequency as my "free" coil in the creek. The system being fired was loaded with discharger, so spark could not break out. Down in the creek I was able to light bulbs from the top of the grounded coil, despite the 1/4 mile distance (and don't forget a creek bank and a rebar wall) between my location and the power supply. This coil was not receiving radiated signal, it was resonating on base fed ground current. Coils can be forced to operate at frequencies other than the natural 1/4 wave by top loading "extra" coils or other resonators on the end of the system. Tesla used this more complex "Magnifier Coil" circuit in the Colorado Springs machine. In the Magnifier, the secondary coil is forced to resonate at 1/8th, 1/16th, 1/32nd, or any other harmonic of the system frequency. A transmission line is used to take CURRENT from the secondary to a RESONATOR located away from the primary/secondary driver system. The resonator may be helical (coil), coaxial, or cavity. In this way the Tesla system may be used as an efficient driver for experiments in other areas of physics. I have wondered about the possible use of a tuned cavity resonate laser tube, or linear particle accelerator. Another guy told me about a Russian using coaxial resonators for fusion. Tesla built a system for the worldwide transmission of electrical power by top loading the "extra" coil (a base fed 1/4 wave helical resonator) so spark would not break out. This forced the tremendous energy to ground. He tuned the system so that the ground current was also earth resonate. This was a double ended resonator system of very high efficiency. The earth acted as a cavity resonator on the base (for the ground current) the extra coil was a helical resonator a with radiating discharger in the air. He stated the system was to be used as a multiplexed wireless transmitter from both the ground and air terminals (he had tuning and harmonic coils in the ground path). ----------------------------------------------------------------- The High Voltage, Pulse Discharge CAPACITOR Many high voltage projects require a high voltage pulse discharge capacitor. Whether your project is a laser, Tesla coil, or particle accelerator, you will need a high voltage rated pulse discharging capacitor in your device somewhere. Commercial units are expensive. Manufacturers of these units do not stock them. Each and every unit is built to order. Off the shelf units do not offer the performance required for most high voltage projects. Off the shelf capacitors get hot, have high loss to output ratios, and will break down in spark excited tank circuits. Some types are a potential explosion hazard. You can build your own capacitors for these projects from polyethylene plastic and aluminum flashing. The following instructions are for a pulse discharging capacitor with a .02 uf at 35-40 kvdc rating. The unit is rated for work in spark excited tank circuits with up to 15 kv rms inputs, 12 kv is the recommended AC rms voltage rating. This is an ideal unit for small to medium Tesla coils up to 4 kva. The material cost is around $100.00 per unit as opposed to $200 - $250 for a custom commercial capacitor with this rating. Materials for this unit are as follows: Three yards of low density, 60 mil, polyethylene plastic. This plastic is available from any good sized plastics dealer. One ten inch by twelve inch sheet of 1/4" plexiglas. One fifty foot roll of 14 inch wide aluminum flashing. This will make 4.5 capacitors. Hardware store. Eighteen inches of 1 inch schedule 40 PVC pipe. Plumbing supply, Two: end caps for the 1 inch schedule 40 PVC pipe. The end caps must have flat bottoms (not rounded) or you will need to cut them. Twenty inches of CLEAN, 6 inch PVC DRAIN PIPE. DO NOT USE SCHEDULE 40! Six inch PVC DRAIN PIPE is available at any good plumbing supply in ten foot lengths. One: six inch PVC DRAIN PIPE END CAP. One gallon of pure U.S.P. Mineral Oil. Two: 1/4 x 20 brass machine screws and four nuts. Two: #8 Pan Head Machine screws with washers and nuts. Screws should be about 3/8ths of an inch or less long. Loctite thread fastener (medium strength) Six or eight: 12" long nylon wire ties PVC cement (medium body, clear, works best) PrepSol (Dupont paint store) or U.S.P. alcohol Four inch stack of clean newspaper or BUTCHERS PAPER Lint free wipes or good quality paper towels. Don't use the cheap stuff. ----------------------------------------------------------------- BUILDING THE CAPACITOR TANK Start out by cutting the PVC drain cap in half. You want to cut a ring 1-1/2" high off the end cap. The bottom of the end cap should be saved intact with a 1-1/2" high side wall. Lay the ring cut from the 6" PVC drain cap on the sheet of 1/4" plexi and scribe a circle. Cut the circle out and glue it to the ring with PVC cement. This forms the clear, see through, lid for the capacitor tank. When the PVC cement has dried, drill two holes through the plexi for terminals. The holes should be on opposite sides of the lid. A small hole is drilled dead center for venting. Cut some strips of plexiglas, 3/4" wide by 2" long, out of the scrap material. Glue one of the 1" PVC end caps to the center (inside) of the 6" PVC drain cap. Glue at least four of the plexiglas strips around the 1" end cap. The strips are placed so that they are flush with the 1" PVC end cap. They should form a "star" pattern radiating out from the center and form a shelf, 3/4" high, for the capacitor roll to sit on. This shelf prevents the roll from resting on the very bottom of the tank and allows oil to circulate. It is important that there is sufficient room between the edges of the shelf and the side wall of the 6" drain cap to allow the 20" section of 6" PVC drain pipe to seat all the way to the bottom of the end cap. When the end cap assembly is dried, glue and seat the 6" PVC drain pipe in place. Use plenty of PVC cement to prevent leaks. Once the end cap is firmly seated in the 6" PVC pipe, then cement the 18" length of 1" PVC pipe down into the center ring. This pipe saves oil, as well as providing a center post for the capacitor roll. Glue the second 1" PVC end cap onto the top of the 1" pipe to seal it. Let the entire assembly dry thoroughly. Clean the tank out well. This completes the capacitor tank construction. ----------------------------------------------------------------- THE CAPACITOR ROLL The capacitor roll is made from the polyethylene sheet and the aluminum flashing. It is important that these materials are absolutely clean and free from defects. Vacuum up a work area large enough to lay all of your plates and dielectric out. If things are dusty you may want to mop. When the work area is clean, lay down fresh newspaper, or even better, butcher paper, over the entire work area. You will need a long, hard, smooth, flat surface to roll your capacitor up on. A clean, paper covered, concrete floor works well, as does a couple of paper covered buffet tables. Cut the poly sheet lengthwise into three equal strips. The standard material width for this sheet is 48 inches. You will get three 16" wide strips from the sheet, though only two strips will be required to make one capacitor roll. The strips must be washed and wiped on both sides with PrepSol or alcohol and lint free wipes or high quality paper towels. Then they must be wiped dry. Static may become a problem here, and the dielectric may collect dust. A ground strap run to a water pipe may be wired to a copper or brass brush. The plates and dielectric may be swiped lightly to ground out static, but do not scratch the material. Cut two lengths of aluminum flashing 102" long. The flashing must be six inches shorter than the polyethylene strips. The material is already two inches narrower. Use a good pair of heavy duty scissors to cut the aluminum. The strips of flashing (plates) must have the corners well rounded, and have all sharp edges smoothed. Trim the corners off with the scissors, then sand all edges you cut it #150 emery cloth. Drill a hole, 1/2" from one end of each flashing strip for the terminal mount. Inspect your plate. It should have no dents, sharp points, "ruffles" along the edges, etc. Many flaws can be carefully worked out. The aluminum capacitor plates must be washed and dried. Fill a five gallon bucket with very hot water and a good squirt of liquid detergent. Roll the plate up and "dip, swish, and swirl" until all the sanding grit, manufacturing oil, and dirt wash off. Rinse the plate well and stand it on its edges on clean newspaper until it is dried. Don't worry if the plates oxidize a little. Lay out your meticulously clean plates and dielectric sheets. Lay one strip of plastic dielectric down first. Then lay a plate on top and center it. The plate is centered so that there is a one inch border of dielectric plastic evenly along the long sides. Line up the end of the plate with the terminal hole flush (even) with one END of the plastic. The far end of the plate will be six inches short of flush with the bottom dielectric sheet. Lay a second sheet of plastic on top so that it is exactly lined up the bottom strip of plastic. Lay the last plate down on the stack and center it. The plate is centered so that there is a one inch border of dielectric plastic evenly on both of the long sides. Now, the first plate you laid will have the terminal end flush with one end of the bottom dielectric, it makes no difference which end; line up the second plate so that the terminal end is flush with the end of the second dielectric sheet, but it must be at the opposite end from the bottom plate terminal. Cut two 1" strips of aluminum flashing 14" long. Tape them together into a 1" strap. Round it and sand it. Then untape it and wipe or wash the strips. Reassemble and punch a hole in each end. One hole for a 1/4" or larger screw (tank terminal), the other for the #8 pan head machine screw (plate terminal). Using a #8 pan head machine screw, mount this strap into the terminal hole on the top plate. Use a flat washer, a tiny drop of loctite thread fastener, and then a nut. Snug the connection down firmly. This strap serves as a high current lead from the plate to the terminal mount on the capacitor lid. Make sure that it is the smooth pan head of the screw pressing into the plastic capacitor dielectric as the capacitor is rolled up; not the sharp screw shaft. Do not allow the sharp threaded end to press into the capacitor. It is a good idea to have a couple of spare patches of 60 or 30 mil plastic to place under the pressure points of the terminal connector screws. This will help prevent breakdown. Starting from the terminal end of the top plate on the stack, the end with the terminal strap already mounted, roll the capacitor up as tightly as possible. Make sure that the top plate does not curl around to touch back on itself on the first turn. A strip of extra plastic here can be helpful. If the first turn of the roll looks poor, then unroll, line everything up, and try again. When the capacitor is tightly rolled, do not loosen your grip. Have an assistant put two wire ties together and slip them over the roll. When the wire ties are cinched, you may loosen up. As you rolled the capacitor up, the first plate in the stack worked its way out of the roll a few inches. This plate should present you with a terminal hole to mount a second 1x14" strap of aluminum for the second lead. Mount the second lead, making sure the smooth screw head is against the capacitor, not the sharp threaded end. You will have one lead coming up from inside the roll, and the other coming up from the outside. Put at least three wire tie strips around the roll. Two 12" wire ties connected together will give enough circumference. Set the capacitor roll into the tank. Fill with one gallon of mineral oil. The roll must be covered by at least a quarter inch of oil to suppress corona and prevent flashover. Note that the oil soaks into the roll. The level will drop after filling, and may drop again after use. Check on it occasionally until the capacitor is fully broken in, a period of about six months. Connect the leads from the capacitor roll to the tank lid. For the tank lid terminals use at least 1/4 inch brass machine screws and tighten down well. The head of the machine screw should be inside the lid, the first nut on top will hold the connection tight, the second nut is removable for connection to your circuit. Do not seal or glue the lid in place. Do not apply the full rated voltage to these units until they have set for at least three days, and the oil has had a chance to soak in to the roll. It is best to start them out at about half voltage, or less, and run them for short periods for the first few days on a smaller coil. These units run on the ragged edge of their voltage ratings, yet they are quite serviceable. On larger coils it is best to put these units in series/parallel to back them up against kickback. Because the material width of the polyethylene is 48", you get three 16" strips of dielectric from cutting a length. You will have one strip left over. Because of this, it is perhaps better to plan on building at least two units at a time. This makes more efficient use of material, but more so for the use of time. Once a temporary "clean room" has been established it makes sense to use it to fullest advantage. When coiling in general it is best to "back up" this capacitance by placing two tanks in series and then placing two series sets in parallel. Thus you need four tanks to equal the value of one tank alone, but the four tanks will withstand twice the voltage. You will find it more economical to build three extra tanks, and run them in series/parallel, than building one tank and having to repair or replace it if it fails before it completes the long 6 month full break in period. Later you can risk the option of running them at their full rated voltage, should you choose, or increase power by playing it safe and building more caps. The effort in building a first class cap is worth the extra time and expense to do it right. The unit will last longer, withstand more abuse, and give you more capacitance if it is well constructed. Once this effort is expended, and the unit is in service, don't blow it. Rather than risk the investment you should build more caps, "backing up" your existing caps and increasing power with additional caps as you go. Don't overdrive these, you will blow them. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-24-93 20:25 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ On 10-20-93 Richard Quick wrote to David Tiefenbrunn... RQ> RQ> The following instructions are for a pulse discharging RQ> RQ> capacitor with a .02 uf at 35 kvdc rating. Thanks for the info. I was talking to another engineer that I know, and I mentioned your Tesla coil. He has a 150W T-coil. We got to talking about spark gaps. It seems there used to be a rather large industry for them, back before vacuum tubes (and even larger than 10KW). One type was basically a stack of convex metal disks, with heatsink fins on the outside. The disks were spaced rather close together (maybe .05"?) but there were MANY in the stack. This spreads the heat around. Maybe something like that with compressed air cooling is a solution. I can try to get more info if you want. He was also aware of *room* sized spark gaps in use back then. Dave (1:320/5967) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-27-93 13:29 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DT> Thanks for the rest of the info. No problem, I hope you find it useful, I sure have. You don't see plans for components like that everywhere. DT> I was talking to another engineer that I know, DT> and I mentioned your Tesla coil. He has a 150W DT> T-coil. We got to talking about spark gaps. DT> It seems there used to be a rather large industry DT> for them, back before vacuum tubes (and even larger DT> than 10KW). One type was basically a stack of convex DT> metal disks, with heatsink fins on the outside. The DT> disks were spaced rather close together (maybe .05"?) DT> but there were MANY in the stack. This spreads the heat DT> around. Maybe something like that with compressed air DT> cooling is a solution. I can try to get more info DT> if you want. He was also aware of *room* sized DT> spark gaps in use back then. I am always interested in more information. I live for the stuff. As to the gaps you are describing, they are called "quench" gaps. The metal discs are separated by gaskets of mica. The mica gasket determines the gap distance between plates. The gasket prevents air exchange, so as the gap breaks in, the O2 is consumed and they run with in a nitrogen atmosphere. These plates were machined to very close tolerances, and the actual electrode surface was kept fairly small. The large plate was used for a heat sink. The best gaps of this type were German made by Telefunken. The advantage of the quench gap is they produce a continuous wave (undamped) oscillation in the tank circuit. They were employed in the first long range Tesla transmitters. Most of the major ship lines (with the exception of White Star I believe) used Tesla transmitters with Telefunken quench gaps. Telefunken had contracts with the shipping lines for gap service, and after so many hours of operation the gap would be removed by a certified Telefunken technician, cleaned and serviced. Per contract nobody else was allowed to break the seals. Telefunken had facilities in every major port. Tesla used disruptive breaks in his demonstrations, but clearly documented that continuous waves from quenched or CW gap systems were used for transmission of electricity (both for power transmission and radio). Now this is where is starts to get interesting. 1/4 wave Tesla systems produce much less spark with a quench gap, but they will light low pressure gas bulbs many yards away, so they definitely radiate much better. But the Tesla Magnifier with a quench gap produces excellent spark, AND radiates over long distances, especially if sparks are prevented by loading it up with discharger. The problem with high powered systems running quench gaps is as you say, the gaps get huge, and you would almost need a cooling tower to remove the heat. This heat represents high loss from the tank circuit. Tesla solved this problem too, but the solution is not well known. He began running multiple phases directly into his oscillators, up to 6 phases in the experimental Colorado Springs machine, and 4 phases in the commercial Wardenclyff plant on Long Island. By using a quench gap system in series with a rotary break running at very high speeds (40,000 BPS and possibly even higher) he was able to obtain CW output from a disruptive (read rotary) gap system. This way he was able to reduce loss, keep the size under control, and still get CW output; at the same time he was able to really increase the power processed by the system. This is the type of system required for more advanced work with coil powered directed energy devices. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-20-93 21:35 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ A couple of weeks ago someone posted me some "new to me" information about Russian RF resonator work that resulted in a machine capable of fusion. I asked for some additional information on this subject, and as of yet I have not heard back. However, I have done some delving of my own and came up with some very interesting information about this guy (P.L. Kapitza). I stumbled across the name doing some related research (yes this thread is based in fact, and Tesla's work has practical apps)... His name is Peter L. Kapitza, and he shared in a Nobel Prize in 1978 with Americans Arno Penzias and Robert W. Wilson for his work in magnetism and the behavior of matter at extremely low temperatures. His work on RF resonators was apparently done much earlier, as I find a reference to "High Powered Electronics" in a Russian periodical, Uspekhi Fizicheskikl Nauk, Vol 78 (November 2, 1962, pp. 181-265). In the same bibliography I find another "more unusual" reference by physicist Jerzy R. Konieczny "New Weapon 'X'" in a Polish periodical, Wojskowy Przeglad Lotniczy, (November 2, 1963, pp. 72-75) apparently referring to a particle beam device... A little more research back to Kapitza, turned up Tesla's name in a quote!!! (See Margaret Cheney, TESLA, MAN OUT OF TIME, pp.284, Dorset Press, 1981, available from Barnes & Noble, 126 Fifth Ave, New York, NY 10011, tel 201-767-7079) The quote is too long to reproduced here (it refers to high powered particle beams), but it clearly shows Kapitza was very much aware of Tesla's work in this country. Tesla was, by the way, the first to investigate "magnetism and the behavior of matter at extremely low temperatures" in the search of super- conductivity for his coils. Kapitza credits him. Tesla lost a laboratory in New York, to fire, at 2:30 A.M., March 13, 1895. The fire is believed to have been caused as a result of liquid air leaking from his equipment. Tesla stated to the fire officials at the time that the air liquidation equipment was the only thing left running in his absence. He used the liquid air to cool his coils for experiments in high efficiency magnetism... Now I'm not saying this means anything... but I keep finding these references dancing around the subject of particle beam weapons, fusion, high energy lasers, and power transmission without wires. These are modern references mind you, not Tesla's; but the deeper I dig, the more I find Tesla's name. I am also finding out more information on involvement of "National Security" interests in these references. I mentioned about James & Kenneth Corum having a paper taken from them after a presentation by the FBI. In Cheney's book (pp. 310) we find this... "the U.S. government has deemed the material important to national security and has been at great pains to conceal it's existence." She is referring to all of Tesla's advanced (and of course unpublished) research and papers taken into U.S. custody at the time of his death. Now I am sick to death of hearing about Tesla conspiracy, ad nauseam. But I ask this based on fact (check em yourself). If the work Tesla did in these areas does not yield workable devices, then why would there be a "national security" interest? Tesla laid the ground work for people like Kapitza, Konieczny, and our own SDI projects. Again, I will state that it is not illegal to build coils or other resonators, lasers, particle accelerators, masers, rail guns, etc. Though I sometimes feel that the government wants everything but taxes made illegal. I am still not able to locate any information in English on Kapitza's RF resonator fusion machine. So whoever sent me the post, please keep digging. Now back to the topic... ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-20-93 00:18 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ OK, back on topic. I just dug up a catalog for some more source material. This one is the Tesla Book Company, P.O. Box 121873, Chula Vista, CA. 91912. They have a 1-800-398-2056 information, catalog, and ordering service. They carry a book "VACUUM TUBE TESLA COILS", and I believe that this is the same book that I am going to be referring to. The Book I am looking at, VACUUM TUBE TESLA COILS, is written by James & Kenneth Corum. You may also contact Corum & Associates, Inc. at 8551 State Route 534, Windsor, OH. 44099. I have met the Corums, they are for real. I see some other publications worthy of note in this catalog: TESLA COIL DESIGNER is a computer program written by my friend Walt Noon, I use this program to determine ball park frequencies and inductances in mathematical simulation before I wind any coil. This software is menu driven and Walt has been very helpful in working out the bugs and adding features with me. It works and saves hours of designing time. I see an entry here for Dr. Nickola Tesla's Diary 1899-1900. This was the time Tesla spent in Colorado Springs working on his monster oscillator, but this does not sound like the preferred reference, THE COLORADO SPRINGS NOTES which includes most of the printable photographs of the lab and the machine. However, the original prints of this work (as I look at my copy) are from NOLIT, in Belgrad, Yugoslavia, and are now expensive. 21st Century Books has copies, P.O.Box 2001, 100 South Ridge St. #101, Breckenridge, CO. 80424-2001, tel. 303-453-9293, but they want $100.00 where I paid $45.00 a few years back. I will have to take better care of mine... Both of these companies sell "new age science", "zero point energy" and "scalar wave" material; which in my opinion is garbage and not worth the paper the printing is on. Now the Corum book which I will talk about briefly, is a piece of hard core electronics engineer stuff, but it is worth trying to muck through for those who don't believe coil driven RF equipment can have "practical" uses in physics and electronics. It contains most of the important facts on "A Technical Analysis of the Extra Coil as a Slow Wave Helical Resonator". This refers of course to the function of the "extra" coil in Tesla's Colorado Springs machine. But the book is much more. Tesla driven X-Ray machines, tapped coaxial helical resonators, particle accelerators, cavity resonators, etc. The book has charts and diagrams even the most novice electronics buff would understand sandwiched between pages of calculus needed to design and construct the equipment. One page (XI-10) shows the development of conducting electrical resonators from Lord Kelvin through Tesla, to Schumann's verification of the earth as an electrical cavity resonator in 1952. Books of this quality are rare, and make excellent reading for anybody interested in high energy electronics. It has an excellent bibliography. In searching for material to lead to coil powered high energy devices I can say that this points to the right directions. "The coaxial geometries do have the advantage of compactness and portability. And, this may be of significance to those interested in directed energy devices." ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-21-93 17:41 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ The Tesla Magnifier What exactly is the Tesla Magnifier, and how does it differ from the standard 1/4 wave Tesla Coil? This question has been asked over and over in the past 93 years. I think I can give some insight into this for a better understanding of the system. A lot of the information I will present here (to the best of my knowl- edge, feel free to prove me wrong) appears in text form for the first time. I have explained in some detail the set up and basic operation of my 10KVA 1/4 wave system. To get a mental picture of how the coils are physically positioned for firing in this 1/4 wave system, imagine a 12" phonograph record, with a Quaker Oats canister sitting upright on the center. The phonograph record represents the wide flat primary coil, and the oats canister represents the 1/4 wave secondary coil. The secondary coil would be topped with a toroid shaped discharger. These coils are "loosely coupled", "coupling" in coil systems refers to the mutual inductance between primary and secondary. The coupling is kept loose because these coils are capable of such high energy transfers that the secondary is overdriven or "split" if placed in too close proximity to the primary. Splitting of the secondary is seen in coils that are over driven or "over coupled". The excess energy absorbed in the secondary coil causes a frequency split with the result that harmonic 1/4 wave voltage peaks appear in the secondary coil windings. These harmonic peaks show up as sparks that break out from the sides of the coil. If the coupling is not loosened, or input powers reduced, the coil will be destroyed in short order. This is a serious limiting factor in 1/4 wave Tesla systems. "Critical" or perfect coupling limits the amount of energy that can be processed through the system. Large toroid dischargers assist in unloading the secondary, and allow for closer coupling, but this is like treating the symptom, not effecting a cure. The problem with the 1/4 wave coil system is that all of the energy processed in the system remains trapped in the secondary until it is removed by spark. As spark lengths and input powers grow, so do coupling problems. Strain is also put on the tank circuit. Energy can flow in both directions in the 1/4 wave system, and secondary energies can unload not only in spark from the discharge terminal, but can also flow back into the primary tank circuit. This results in nightmarish problems "quenching" the arc at the main system spark gaps. In theory no more than 50% of the input energy can be converted into discharge off the secondary air terminal, as both primary and secondary energies equalize before a break can be effected at the main system spark gap. Once the break (open, non-firing spark gap) is made, the secondary energy is trapped, and must be radiated or discharged. Tesla realized that critical coupling limited the efficiency of the system, and came up with a unique solution. He added an "extra" coil to the secondary. The extra coil is a normal 1/4 wave helical resonator, or Tesla secondary. The coil was placed away from any inductive effects of the primary/secondary "driver" coils, and was bottom fed by transmission line with the output of the driver secondary. Tesla was able to determine certain "harmonic" shifts in the system, but nobody else was able to figure out what was happening for years and years. What is happening is this. In order for the "extra" coil to function properly it must be fed RF current that matches it's natural 1/4 wave frequency. In order to provide a working system, the output of the secondary driver coil in his three coil Mag- nifier must be shifted away from it's normal 1/4 wave output. The normal 1/4 wave output (high voltage peak) of the Tesla secondary must be shifted to a lower harmonic in order for the extra coil to receive current. If you base fed an extra coil with 1/4 wave voltage peaks, all you would get would be sparks from the transmission line, and a fire at the base of an extra coil (I've done it). Experiments, and review of Tesla work show that the 1/8 wave harmonic is preferred. The extra coil will cause some shifting of the driver coil output, but the system operates best when THE DRIVER COIL IS WOUND WITH THE PROPER LENGTH OF WIRE TO FACILITATE 1/8th WAVE OUTPUT. This boosts efficiency in several ways. First, the energy in 1/8th wave output is about 20% greater than the energy of a 1/4 wave peak. The 1/8th wave location on the sine represents 70% of the wave energy, as opposed to 50% of the energy at the 1/4 wave point; the 1/8 wave point being the product of both current and voltage at this location on the sine. While this may seem a little technical to the novice, a 20% gain is realized by shifting the output to the lower, 1/8th wave harmonic. The second increase in efficiency is due to the fact that the secondary, or driver coil, is no longer responsible for the end processing of the system energy. The majority of the resonate rise, or VSWR, occurs in the uncoupled resonator located some distance away, and fed by transmission line. The secondary is no longer stressed by a high voltage point at the top of the coil, and the current produced in the secondary is removed rapidly by the transmission line to the end resonator (extra coil). The third boost to efficiency is the ability to tighten the coupling between the primary and secondary driver set. The coils can be placed with much greater mutual inductance (tighter coupling). Energy can then be forced into the driver in much larger amounts without the problems of splitting and breakdown. The coils can be arranged more like two nested buckets, with one inside the other, as opposed to a phonograph record with an oats canister on top. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-30-93 09:55 From: Richard Quick To: Guy Daughterty Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ GD> Well, yeah, Richard. We all think you're wacky, and keep GD> looking toward your direction on the planet waiting to see GD> the kaboom. GD> So, once the atmosphere DOES light, how do we turn it off GD> again? -!- On your last question: Turn off the switch. I use multiple interlocks in case one or two fuse closed. Had it happen on the arc welder current limiter once. When I opened the cabinet to repair the switch, I noticed the variable shunt was also stuck and there were signs of arcing. But it is an arc welder... First remark: Keep looking. Probably won't be a kaboom though, more like a bazzzap. Obviously even you see the potential. But if everybody thinks I'm wacky, should I stop posting? I don't want to waste people's time. I just thought you all were interested. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-30-93 10:02 From: Richard Quick To: Guy Daugherty Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ GD> Well I have a Jacob's ladder on an old theater marquis neon GD> transformer. Really makes the kitty stop and pay attention. GD> Worries people who see it, too. My inner Beavis loves it. Yeah, I have some videos of the pole pig settin on the garage floor with 3/8" copper pipe rails. Pulls arcs clear to the rafters. Running the tape in slo-mo shows plasmoids forming at power levels over 5KVA. I have also messed with doping the rails with salts which modify the colors. You can get some pretty good Halloween effects with a couple of old neons and some strontium or lithium salts. By the way Guy, what grade are you in? ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 10-30-93 16:13 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Dave, I got your package in the mail today, and your tape went back out. It is after the pickup time on Saturday, but you should have the tape by midweek. Let me know when you get it, and what you think. I am sorry I had to cut a lot of material out, but two hours just doesn't seem to be enough time to give you the tour, show you some techniques, and show all of the systems. I cut back on a lot of smaller test and prototype stuff to let you focus on the big coil. If your interested in anything else, just let me know. ... And if all else fails... Put another megavolt through it