Date: 12-01-93 00:01 From: Dave Lyle To: Richard Quick Subj: 1,000,000Kva Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>coil "converts" the base current into a voltage at the other RQ>end. Since this voltage rises as you go higher and higher up RQ>the coil, and reaches it's peak at the top; Tesla was able to RQ>determine the voltage at the top of the coil is the first 1/4 RQ>wave voltage peak of the RF current fed into the bottom. Richard, GREAT series of articles here. Just a quick question here. First, I understand what is happening as far as the 1/4 wave length is concerned. I relate this to transmission line theory, where the VSWR is approaching infinity. My question though, is..how does the coil excite at other odd multiples of 1/4 wave, i.e. 3/4, 5/4 wave? I suspect it would be more lossy, but what, if any, benefits might be derived by operating at the higher frequency? Dave ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06 Dec 93 13:12:00 From: Richard Quick To: Dave Lyle Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DL> Richard, DL> GREAT series of articles here. Thanks! Another vote of confidence! DL> Just a quick question here. First, I understand what is DL> happening as far as the 1/4 wave length is concerned. I DL> relate this to transmission line theory, where the VSWR is DL> approaching infinity. You are correct in this relation. Transmission line theory does apply to Tesla secondaries. DL> My question though, is.. how does the coil excite at other DL> odd multiples of 1/4 wave, i.e. 3/4, 5/4 wave? I suspect it DL> would be more lossy., but what, if any, benefits might be DL> derived by operating at the higher frequency? Coils that are excited or driven to higher harmonics (over 1/4 wave) break down prior to the top turns. For instance a coil driven to 3/4 wave resonance would still break down at the 1/4 wave point of the winding. This problem is commonly seen on coils that are overdriven or overcoupled, and I cannot imagine any way to insulate against this breakdown. Higher harmonics CAN be reached by using two or more coils driven from the same tank circuit or by placing the primary in the center of a single coil. For instance a 1/2 wave system could be built using two coils, or driving one coil from the center producing two 1/4 wave peaks, one at either end. The trick to efficiency is to excite at a LOWER harmonic (below 1/4 wave), ie: 1/8th wave, 1/16 wave, or 1/32 wave. These lower harmonics are high in current, and lower in voltage. Loss is reduced because the lower voltage leaks less, and the energy of the wave is a product of both current and voltage. The 1/8th wave harmonic appears to be the most efficient. Now remember that we have not changed the frequency. The system frequency may remain the same, we are simply tapping the energy further back in the wave form. Tesla was able to force the secondary into these lower harmonics by the addition of the extra coil to the system, then reducing the number of turns in the secondary until it was 1/8th wave resonate. Current and voltage were then fed to the base of the extra coil resonator. The advantages of using the extra coil, and tapping the secondary energy at a lower harmonic are many: Coupling between primary and secondary may be tightened up considerably, driving more energy through the system; the 1/8th wave output of the secondary contains 70% of the wave energy as opposed to the 50% obtained in 1/4 wave output; there is much less voltage stress on the secondary which reduces the incident of breakdown and "splitting" (parasitic 1/4 wave peaks); current is removed from the secondary by transmission line to the extra coil, unloading the secondary for more input (allows higher break rates in the gap = greater throughput) and placing the main system VSWR in the uncoupled end resonator (extra coil); impedance, resistance, and distributed capacitance are also reduced with proper design and construction. This production of a lower harmonic from the secondary by adding the extra coil to the system is a true breakthrough in Tesla power processing. This is the three coil Tesla Magnifier as Tesla developed to industrial proportions in Colorado Springs, and may be scaled back for very efficient "basement" systems. I have seen Magnifiers producing 100"+ arcs at 4100 watts input power, and have myself hit 72" with inputs around 2500 watts. I see a real gain of 40% in spark length for input power with this system. Thank you for your input on transmission line theory and your question. I hope I have given a reasonable and satisfactory response. If you have any other questions or comments I would be more than happy to reply to them. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06 Dec 93 11:17:00 From: Richard Quick To: Joseph Freivald Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ JF> For those of us who are wanna bees, What's a Tesla coil, and JF> why does it get at least 10 posts per day? A Tesla Coil is an air core, RF resonate, transformer. It is a very efficient source of very high voltage RF energy. If it weren't for the problem I am having with my ASCII character set I would give you a wiring diagram. Basically you take a high voltage pulse discharging capacitor and connect it to a large heavy coil. The cap is charged with a high voltage power supply (neon sign xfrmr, potential xfrmr, or power distribution xfrmr run backwards). The circuit consisting of the cap and coil is excited by discharging the cap through a spark gap. This way current of hundreds of amps at thousands of volts oscillate through the coil. Frequency of oscillation is dependant on the number of turns in the coil and the size of the cap. This is the basis of the Tesla Tank circuit. The secondary coil or "Tesla coil" is a hollow form with several hundred turns of wire. This coil has a natural RF resonate frequency based primarily on the length of wire used in the winding. The tank circuit frequency is made to match the secondary natural frequency by tuning, changing the number of turns in the heavy primary coil or changing the value of the pulse discharging capacitor. When the tank circuit frequency is matched to the secondary frequency, and the coils are placed in close proximity, energy is exchanged and transformed. RF voltages in the megavolts can be achieved with very high efficiency. The tank circuit literally converts line current into a series of rapid pulse discharges with peak powers in the megawatt range. A simple coil setup is capable of producing more or less continuous spark discharges several feet in length, or longer. I cannot say why there are so many posts on the subject, except that the topic is interesting and I have had more than a few requests for information on these systems. I have sent out a few video tapes with some of the work I have done, and it has greatly accelerated the interest. My video features a coil system I built operating with 10,000 watts input power, generating peak powers of 22 megawatts, with a discharge voltage of between 3-5 megavolts (or more). The system is able to produce arcs of synthetic lightning that strike out up to 15 feet. I hope this answers your question. If you need any additional information, or have other questions, please feel free to post on this topic. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06 Dec 93 11:33:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>A tank circuit with a small capacitor, and a large primary >inductance, will reach down to the lower frequencies of >operation. A tank circuit of this design will use less power, >and therefore require a smaller step up xfrmr. The capacitor >will be smaller, which further reduces the cost of the >system. DH> Makes a lot of sense! Efficiency, efficiency... Put every watt into the discharge! RQ>So to give some advice to my friend Dave Halliday, who is >building a 6" secondary coil sometime in the near future, >plan on winding a primary coil from a conductor material that >I have listed above, and use a conductor length of around 75 >feet. Your primary should end up about as wide as, or wider, >than your secondary is tall. DH> Got it! I was thinking of using some 3/8ths refrigeration >tubing but since the surface area is important, I'll probably >get a reel of 3/4ths or 1/2" tubing ( gotta check on pricing >first ) With a 6" secondary coil that is 24" high, 3/8" soft copper water pipe is perfect. My big coil uses 1/2" pipe and only gets slightly warm on the first and second turns after a five minute full power run. Balance the diameter of the pipe to the length of the primary conductor. 50' conductor use 1/4" pipe, 75' conductor use 3/8" pipe, 100' conductor use 1/2" pipe. When in doubt use the next size up. DH> Trade some videos / photos once I get something to show. COOL! ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06 Dec 93 12:45:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ DH> There is a local park that is situated on Lake Washington DH> near where I live, I have been toying with the idea of DH> firing the coil off there, maybe out on one of the boat DH> docks. Drop a bunch of Aluminum flashing over into the water DH> for the ground. DH> Could be kind of fun! I have fired and grounded off of water grounds exactly as you are thinking. They work great! Good Luck! I hope to see a spark shot or two soon. Bring the camcorder, and a 35 mm, and a few friends. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 06 Dec 93 13:11:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ OK, People who are interested in the TESLA VIDEO have not, are not, and will not be disappointed. I will send a full 2 hour SP recorded, one off master, VHS tape with sections showing my big coil literally burning up the back driveway and striking everything within 11 feet (arcs as big around as my leg on some strikes). You must send $10.00, a self addressed postage pre-paid return mailer, and a blank, high quality VHS tape. Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 USA Tapes are sent out within 48 hours from receipt of your package, there is no monkey business. The video is instructive: it shows several coil systems in operation, details on the power control cabinet, wiring, tuning and firing as well as sections on spark gaps, RF filter chokes, etc. I also fire my "pole pig" utility power distribution transformer in a Jacob's Ladder at 8000 watts with 20,000 volts across the rails. This tape is my cutting edge 1/4 wave Tesla work, and involves lots of high voltage set ups and demonstrations. Due to the nature of the work covered on the video: I CANNOT BE RESPONSIBLE FOR THE SAFETY OF ANYONE ATTEMPTING TO REPRODUCE ANY OF THE SYSTEMS OR EXPERIMENTS FEATURED ON THE VIDEO!!!! I am more than happy to answer any questions or respond to comments in this area on anything covered on the video. I will also trade tapes even with people who are engaged in similar or other work of interest: Tesla coils or other high voltage equipment in action, rail guns, laser setups, taser guns, particle accelerators, capacitive discharge machines, etc. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-10-93 23:51 From: Dave Lyle To: Richard Quick Subj: 10Kva Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ> I have a normal Tesla secondary that resonates at about 200 RQ> kHz with a discharge terminal. When this coil is placed in a RQ> primary and critically coupled, it will fire when the tank RQ> circuit is tuned to 200 kHz. No problems here, this is a RQ> normal 1/4 wave system. The tank circuit oscillates at 200 RQ> kHz, the secondary coil with discharger resonates at 200 kHz, RQ> and the output from the system is the 1/4 wave peak of a 200 RQ> kHz signal. RQ> Now we remove the secondary from the primary and replace the RQ> secondary with a coil that is 1/4 wave resonate at 400 kHz. Hi Richard, I was actually wondering what would be the effect of going the opposite way. What if you removed the _primary_ and replaced it with one that resonated at 600 Khz. Now the secondary would be resonate at 3/4 wave, and the voltage/current distribution would be: At the base.........................Current peak, Voltage null At the 1/4 wave point (1/3 of the way up the coil).....Voltage peak, Current null At the 1/2 wave point (2/3 of the way up the coil).....Current peak, Voltage null At the 3/4 wave point (Top of coil)...................Voltage peak, Current null I suppose you would have trouble preventing a breakdown at the 1/4 wave (1/3 of coil) point, but would there be any advantages to the higher frequency operation? 414-476-8468 (1:154/100) ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-12-93 12:12 From: Robert Taylor To: Richard Quick Subj: Re: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Wanted to drop you a line & see if you got my post about a month ago on the book that Barnes&Noble has out called *The Inventions, Research, and Writings of Nikola Tesla*. Got a new catalog from them the other day & saw that their price had gone down to about $10. Good book w/ a lot of the heavier technical stuff (including original schematics). Definitely worth a look. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 14 Dec 93 12:19:00 From: Richard Quick To: Dave Lyle Subj: 10Kva Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>Now we remove the secondary from the primary and replace the RQ>secondary with a coil that is 1/4 wave resonate at 400 kHz. DL> I was actually wondering what would be the effect of going DL> the opposite way. DL> What if you removed the _primary_ and replaced it with one DL> that resonated at 600 Khz. Now the secondary would be DL> resonate at 3/4 wave, and the voltage/current distribution DL> would be: > At the base.........................Current peak, Voltage null > At the 1/4 wave point > (1/3 of the way up the coil).....Voltage peak, Current null > At the 1/2 wave point > (2/3 of the way up the coil).....Current peak, Voltage null > At the 3/4 wave point > (Top of coil)...................Voltage peak, Current null DL> I suppose you would have trouble preventing a breakdown at DL> the 1/4 wave (1/3 of coil) point, Trouble would be a mild word for it. The 1/4 wave voltage peak appearing in the windings would destroy the coil in short order. RF voltages in these frequencies just don't understand what "insulation" is. I have not found any practical material or construction technique that would contain the voltage of a solid 1/4 wave voltage peak that appears in the coil windings. Plate glass, 1/4" thick polyethylene, etc. are invisible to this discharge, and the energy passes right through it virtually unimpeded. Mineral oil is the best insulator for this particular energy, but there is insufficient space between turns on the coil for sufficient breakdown protection. Even if there was enough room between turns, then you have problems with the coil form breaking down. I have done experiments with coils in which the same basic end result was achieved by bottom feeding an extra coil with current that resulted in higher harmonic resonances of the extra coil (such as the 3/4 wave harmonic you charted above). When the coil was fired, sparks and corona came flying out of about a dozen turns in the coil. Those turns where spark and corona appeared, corresponded to the 1/4 wave peak. But there was no way to contain it. The sparks broke down the windings, scored, then carbonized the coil form . The coil suffered irreparable damage and had to be scrapped. Similar incidents with other systems where energy densities were high resulted with the spark from 1/4 wave peaks in the winding blowing holes through the coil form. Again the coil was a complete loss and had to be scrapped. In addition to the breakdown, the remaining turns further up the coil had no energy at all to speak of. Why? All the energy in the system was lost to spark and corona leakage at the 1/4 wave breakdown point, insufficient energy remained in the coil windings above the breakdown to do anything. DL> would there be any advantages to the higher frequency DL> operation? None that I can think of. This model represents a very high loss situation. 1/4 wave voltage peaks represent the final output point in a coil system. There is no way to process the energy in wire to any point above 1/4 wave in a single coil without tremendous losses. However when you go to two or more coils, where you are working with more than one output terminal, it is possible to achieve 3/4 wave signal processing. This requires a pair of 1/8 wave driver coils, two primaries run in series off the same tank circuit, and two extra coils. Your outputs from the extra coils are still 1/4 wave with the peaks on the terminals, but taken as a whole the system does efficiently process a 3/4 wave signal. This system would be adding up lower harmonics (two 1/8th wave outputs, with two 1/4 wave outputs) to get to efficient 3/4 wave signal processing. This system would be unique in that it may not require a ground, as the two tuned sets of coils could "beat" off of each other; in other words the nul voltage current output from the base of one 1/8 wave driver coil could be fed into the base wire of the second driver. This system would require that the series run primaries, and the drivers and extra coils be wound in opposite directions to achieve phase differential. The base wire current output of one coil becomes added input to the base of another. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 14 Dec 93 12:33:00 From: Richard Quick To: Robert Taylor Subj: Re: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> SEZ Robert Taylor to Richard Quick <=- RT> Wanted to drop you a line & see if you got my post about a RT> month ago on the book that Barnes&Noble has out called *The RT> Inventions, Research, and Writings of Nikola Tesla*. Yes I did. I take it then you missed my reply. I own a copy, and a copy of nearly everything else worthy of note on the subject. I have posted a bibliography for source material on his more advanced work. The book you mention is drawn from his public lectures and other "public domain" material. Things really start getting good when you access sources of material he produced that were never intended to become public. This private material, when combined with his patents and patent applications, reveals much larger plans. Thank for checking up, and the book does make very interesting reading. It covers some of his early work in good detail. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-14-93 14:23 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>Look forward to seeing some video/photos of your coiling work >soon. BTW did you really decide to lengthen the 6" coil form >from 24" to 30" in height? I would think this would require >more than the 1500' of magnet wire you had earmarked for this >project. I was thinking of 30" all along. That stays within the 1:5 aspect ratio limit. The thickness of the wire that I got will allow for 940 or so turns in 30" of length which works out right at 1500' feet of wire. RQ>Also, I am seeing posts that you have quoted from others, but >I am not seeing the original posts here.... RQ>This looks to be a network problem, unless these people are >posting to you locally.... I wonder what is going on. I had been using another BBS for the FIDO messages and they were having some problems with missing messages. I will be using SLUG-BBS from now on until I get my Planet Connect dish up and running. It is sitting in the store right now but I need to get on the roof and cut a hole through the ceiling for the feed- through and of course ( being Seattle ) it is raining pretty much continuously... Maybe August if I am lucky Anyway, when the dish gets set up, I will start my own FIDO feed to my BBS. RQ>I sent you a post last week mentioning that I saw you had made >a local logon here to the SLUG BBS, we narrowly missed a chat. >How long have you been calling locally? If you get the chance >since it appears you have a high speed modem you can grab the >thread here if you have any network problems. This board has >nearly all of my original posts in this conference still >available. I already grabbed them - I had called a few times from home but the modem I am using there is an older one and it sometimes hangs. I will be calling from the store now. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-14-93 14:30 From: Dave Halliday To: Brian Carling Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ BC>thanks for the info. I am going to see what I can find at the >local library also. Although I have not really researched Tesla's life all that much, from what I gather, he kept critical stuff from his patent applications because he had been screwed by Marconi and others. You need to read between the lines. DH> You could scale down the design but I feel that the amount of DH> time and money involved would be about the same regardless of DH> what size coil you are building so why not go for a bigger DH> one. BC> No, I want to build the BIG one! How big? DH> The one I am building is 6" diameter, 30" tall and is powered DH> by a bank of four neon sign transformers. BC> That doesn't sound too huge to construct... It struck me as a nice size - large enough to produce nice 5' arcs but small enough as not to overwhelm my workshop or my budget. BC> Do you connect the neon sign transformers in series or what? A combination - the transformers are 12kV at 30mA so I will get 24kV at 60mA by using four of them. DH> Down the road, I would like to experiment with a "pocket" DH> coil or a tabletop model but you do need a very very good DH> ground regardless of the size so this isn't something that DH> you could take somewhere and casually set it up and expect to DH> get good results. BC> Why can't the one you describe be a "table-top" model? > 6" around by 30" tall would fit on most tables! Yeah but I was thinking about one that was maybe 3" dia and 12" tall. That would be impressive if it threw out foot-long arcs and from what all of the other designs of this type do, the arcs are several times longer than the length of the primary. Imagine something sitting on the table, a foot tall and two feet or so in diameter ( the flat primary coil ) throwing off two foot long arcs! DH> Anyway, keep tuned to this conference and I will be letting DH> people know how things are progressing! BC> I'll watch eagerly! Hey - start planing something! Get some neon transformers, some stuff to make the capacitors and a bunch of magnet wire and start building! ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-15-93 11:04 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ RQ>Good Luck! I hope to see a spark shot or two soon. Bring the >camcorder, and a 35 mm, and a few friends. DH> I am going out of town for fifteen days over the holidays DH> but I should have something in a month or so after that. DH> Have a lot of the raw materials - stuff for the capacitor. DH> Need to get the neon transformers and actually wind the coil DH> and build the base to hold the primary. Things have been DH> extremely busy at the store so I haven't had too much DH> "spare time" but January has always been pretty slow. Great, then at least you are in the planning stage and are organizing yourself for the various constructions. DH> Anyway, I am now getting the feed directly from SLUG-BBS so DH> there should be no missing messages. And no delay!!! ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-15-93 12:11 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> SEZ Dave Halliday to Richard Quick <=- RQ>Thank you Dave for sending the magazine with the article on >the spark gap transmitters. It was interesting, but full of >miscrediting. The author chose in many instances to detail >the worst systems of the era. DH> I thought you would get a kick out of it. I had intended DH> you to keep the magazine - that was why there was just the DH> return mailer for the disk. If you want, I can pop it in DH> the mail again. No need. I copied everything that I wanted. DH> Anyway - I figured you would have some fun with the article. DH> I have not made any major study of Tesla's life but what I DH> have seen ( Man out of Time by Cheney (sp?) plus a couple DH> other articles ) makes me realize that he is very much an DH> un-sung hero of electronics. He was THE electrical genius of his time. >I just find it galling that he would go through such efforts in >accuracy this area and would only mention Tesla's name once. DH> Yeah - it is like he is just copying the "party line" of the DH> people who claimed to "develop" the equipment without doing DH> any research on his part... Exactly. Tesla developed and experimented with every type system mentioned in the article before the people credited for these systems. >The gaps would not quench well at these power levels, and the >short primary conductor does not provide sharp tune, good >coupling coefficients or energy transfers. Tesla's systems of >this era were much much more advanced. DH> The three turn primary also caught my eye. Plus the DH> capacitance was probably huge and lossy - oil filled wooden DH> boxes... Yeah, the signal generated by this system would have been highly erratic. The pulses would have been very intense due to the capacitor size, but the output had to be a far cry from being a "smooth" powerful signal. Tesla on the other hand was using a tiny capacitance in a "balanced" tank circuit with very close coupling, and extremely fast quenching, ultra high speed gaps. He processed only 250 kVA (50 kVA less input power than the large Marconi xmittr) in Colorado Springs, but his output was CW, frequency stable, beat free, RF signal. His power processing efficiency was over 70% from the supply line to the antenna mast. His antenna current was a modest 1100 rms amps, with a peak power in excess of 10 gigawatts. Not bad for a guy in 1900 with a shoestring budget and salt water/glass caps. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-15-93 13:28 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> SEZ Dave Halliday to Brian Carling <=- BC>Do you connect the neon sign transformers in series or what? DH> A combination - the transformers are 12kV at 30mA so I will DH> get 24kV at 60mA by using four of them. Nope, won't work. Each secondary coil in the neon xfrmr is grounded to the core. This setup will not allow the secondaries to be placed in series. Other type xfrmrs may be placed in series, such as plate, potential, and pig xfrmrs, but not neons. The secondaries may be placed in parallel for higher currents, but you are voltage limited. This is OK really because you will have trouble making or finding caps that will hold up to 24 kvac pulse. The primaries on neons are not grounded. The primaries may be run in parallel, so you may gang up as many as you want at 120 volts as long as your circuit will stand up to the load (which may be surprisingly high if you don't use pfc capacitance). However for anything larger than 1.5 kVA you will most likely be looking hard at 240 volt operation to reduce the current load. In this case you may take two neons of the same rating, place the primaries in series, and throw 240 across the two units. The secondaries are all parallel wired to the high voltage buss, regardless of the arrangement of the primaries. This way really large power supplies may be built up slowly, by simply adding pairs of neons to the bank. I have run up to 12 neons (6 pairs wired for 240 volt operation) for power supplies in excess of 4 kVA for medium sized coil systems. Phasing is important in running banks of neons. Not all neons are wired in the same direction. If the primary or secondary coils are reverse wired on some units, they will cancel out other units. A little time may be required to make sure that all of the neons are wired in phase. Nothing special is required to do this, just identify the out of phase unit, and reverse the line power connections, or reverse the secondary connection to the HV buss. You should also make sure to run any HV power supply off a variable autotransformer (variac). This way output voltage to the experiment may be controlled smoothly. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 16 Dec 93 17:35:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Again referring to Tesla: DH> Yeah - I heard that he was sitting on a bench somewhere and DH> the motor came into his head completely formed. Just DH> sitting there in his imagination, running smoothly... This is apparently true, Tesla told the story on more than one occasion. Many other notables of genius status have said their greatest ideas came in similar fashion, or in dreams; but few were as prolific as Tesla. It seems that ideas like this came to him very frequently over a number of years. He complained more than once that it was simply impossible for him to act on all of them. Tesla read Edison's quip that invention was "1% inspiration and 99% perspiration" and remarked that the inverse was in fact the truth. He stated that he was able to operate sophisticated mechanical and electrical devices in his head to determine feasibility prior to drawing or constructing the actual device. He followed this statement up by saying that he never built a device that did not operate as anticipated. In his later years, after failing to fund the Wardenclyff transmitter to completion, he was unable to maintain a laboratory. He did not stop inventing however. He set his MIND to work building, testing, and operating equipment. The result of his purely mental efforts were designs for such devices as particle beam weapons. This mental work came into tangible existence in the form of drawings for such components as the open ended vacuum tube (one end open to STP) for generating high energy particle beams. It is one of the true crimes against humanity that he was so misunderstood that even a small lab could not be furnished to allow him practical creative outlets, though much blame may be laid to him for his ignorance of financial affairs, and his refusal to retain a business manager to see to those affairs. He spent money like water, money having no real value to him. He allowed people to purchase valuable patents outright instead of insisting on long term royalty agreements in addition to the lump sum payments, which would have insured some future income. Had he been monetarily wiser, he would not have died penniless, and many more ideas could have seen commercial application; even if the final marketing was done by others. Have a good vacation, I look forward to hearing from you upon your return. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-19-93 11:08 From: Robert Taylor To: Richard Quick Subj: Re: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ -=> Quoting Richard Quick to Robert Taylor <=- RQ> Yes I did. I take it then you missed my reply. Looks like you're right. I think the BBS that I picked you up on was having some problems around that time, so end of mystery. RQ> I own a copy, and a copy of nearly everything else worthy of RQ> note on the subject. Guess I shoulda known better on that one! You must have one heckuva Tesla library. RQ> intended to become public. This private material, when RQ> combined with his patents and patent applications, reveals RQ> much larger plans. I can only imagine how interesting some of this material must be. I was aware of some Hungarian translation of his private papers was out there, but have never seen a copy of same. Just out of curiosity, are you familiar with anything regarding Tesla's connection with the "project invisibility" & the U.S.S. Eldridge? Ran across something that connected him with the project, but everything that I've seen is vague. An impression was left that he may have had something to do with the building of the alleged field-generator. BTW--did catch your reply on my post about Ken Strickfadden. His work always amazed me. Seasons Greetings & Happy Holidays. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-21-93 14:03 From: Richard Quick To: Robert Taylor Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Regarding: The Inventions, Writing, and Research of Nickola Tesla available from Barnes & Noble Booksellers RQ> I own a copy, and a copy of nearly everything else worthy of RQ> note on the subject. RT> Guess I shoulda known better on that one! You must have one RT> heckuva Tesla library. Over 200 separate covers at this time. A lot of the material I have read two, three, even four times looking for clues. RT> I can only imagine how interesting some of this material RT> must be. I was aware of some Hungarian translation of his RT> private papers was out there, but have never seen a copy of RT> same. I believe the book you are referring to is the Colorado Springs Notes, which were hand written in English in 1899-1900. These papers and many others were processed by the Office of Alien Affairs at the time of Tesla's death (though he was a full citizen...). Tesla had no relatives in this country. Before his death the Yugoslavian government had declared him a national hero (while we were busy starving him). When the Yugoslavs found that he was completely destitute, they set up a trust fund to see that he received a monthly check to cover his food and rent. It was all he had when he died. Since the Yugoslavian government was taking responsibility for his care, the U.S. government declared Yugoslavia the next of kin. The personal effects found in his hotel room were pilfered (many valuable items were stolen), and what remained were sent to Belgrade where they were placed in a museum. In the mid 1970's the curator of the Tesla Museum in Belgrade cataloged all of the papers written by Tesla in Colorado Springs. About this time "pilgrims" such as Robert Golka began showing up at the museum to read the originals. The curator decided to publish through NOLIT of Belgrade, and copies were made available in the U.S. for around $45.00 for a beautiful gold leaf, leather bound edition. Today my copy is worth over $100.00. The book has reprints of most of the surviving photos Tesla took of the lab, it's contents, and some of the experiments performed there. It should be noted that Tesla was very proud of his U.S. Citizenship. He spoke five languages fluently, but English was his mother tongue. All of his patents, articles, and interviews were conducted in English, and all of his notes were in English. RT> Just out of curiosity, are you familiar with anything RT> regarding Tesla's connection with the "project invisibility" RT> & the U.S.S. Eldridge? Ran across something that connected RT> him with the project, but everything that I've seen is RT> vague. An impression was left that he may have had something RT> to do with the building of the alleged field-generator. This area would most definitely fall under the protection of National Security interests, and as such would be highly classified if the project did in fact take place. I have never seen any concrete proof of this project or Tesla's involvement. But that does not stop the stories and conspiracy theories. I have heard more than a few. I cannot say if any of this is worthy of believing or not, as I base my information on facts not hear- say. Nobody to my knowledge has presented verifiable facts on this. But it is a fact that to this day the U.S. government has a Top Secret classified archive in Washington D.C. which contains the bulk of papers Tesla wrote in his later years. Some of these papers are believed to have originated from his hotel room, but the bulk of these papers (many boxes) were removed by the Office of Alien Affairs from his rented storage room. They were not turned over to the Yugoslavian government because they were not considered to be "personal effects". It is my understanding that these papers concern Tesla's particle beam weapon plans, and more likely than not the field generator plans if they do exist. As I have stated, the existence of the archive has been established, as well as the fact that many unpublished documents written by Tesla reside there. The exact catalog of documents is a mystery. It is interesting to note that 50 years after Tesla's death, the U.S. government still considers these documents to be of the gravest concern to national security. Related filings under the Freedom of Information act has revealed clues on some of these documents. It is a known fact that the powerhead design for a coil driven particle beam weapon resides there. This powerhead was a vacuum tube open to the air at one end. Vacuum was maintained at one end of the tube by using a vortex of compressed air, so the tube geometries are similar to an aspirator pump. The tube contained a standard capacitive discharge rail gun at the low pressure end which produced and accelerated metal plasma. The main system energy was given to the plasma from a large Magnifier system (believed) which provided voltage to further accelerate the plasma to near light speeds over a very short distance. I have seen reproductions of original unpublished sketches that Tesla made of this powerhead that were included with his papers sent to Belgrade, and brought to light by one of the "pilgrims" returning in the late 1970's. I have no doubt as to the authenticity of the information I saw, as there was a representative of the museum in attendance when the sketches were viewed and discussed, and the reproduction bore the identical museum authenticity stamp that my published copy of the Colorado Springs Notes bears. Back to your subject of "project invisibility", I have heard nothing but rumors. I heard a guy a couple of years back who claimed to have seen Tesla at White Sands early in the war working on a classified military project. This story could not be verified, and the teller offered no proof. Good story though. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 08-18-93 20:50 From: Richard Quick To: Terry Smith Subj: Tesla Coils ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ High power lighthouse triodes are available from Vacuum Tube Industries, Inc. 506 North Warren Ave., P.O. Box 2009, Brockton, Massachusetts 02405-2009, U.S.A, tel 1-800-528-5014 outside MA. New and reconditioned (I believe they can recondition most any power tube). Xformers, water cooling recirculators, thyratron SCR & sat. reactor control units, the works... Prices are a little high, but if the builder were so inclined a tube and supply xformer for a few hundred could be had, and the rest can be matched and scrapped together for some mean tube coilin. If you fry a filament or puncture a plate they can patch'er right up. Coils built from these type tubes tend to run about 400-450 khz, so the spark length is not much over three feet (only three!), but the current in the discharge would be awesome. Any thoughts? ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 28 Dec 93 12:51:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Well I hope everyone had a happy holiday. I am now recovered enough to post some more specific info on Magnifier construction and operation. I have covered some general material on this revolutionary Tesla coil system, but will now endeavor to throw out some specific pointers for those of you who have an interest in this much more efficient RF power processor. As I have mentioned the Magnifier is a three coil system. The primary is excited from a Tesla tank circuit, the secondary coil is inductively coupled to the primary, and the extra coil is top loaded on the secondary in such a fashion as to be uncoupled completely from the primary/secondary "driver" coils. The extra coil is base fed by transmission line, which can be anything from Litz wire, copper pipe, or heavy DC transmission wire. The keys to getting an efficient Magnifier setup in operation can be listed fairly easily: Close coupling between primary and secondary, good gap quenching, and proper impedances in the secondary driver and the extra coil. Coupling in Tesla magnifiers must be tight. Classic style vertical helix primaries are very practical for use in Magnifier systems, but heavy insulation between the coils must be used to prevent flashover. The close coupling reduces somewhat the VSWR in the driver secondary, and the 1/8th wave output contains substantially less voltage than a normal 1/4 wave Tesla system, but the close physical proximity between coils means flashover will be a problem. Use several layers of polyethylene plastic around the secondary, and insulate the top primary turns with heavy vinyl hose. It has come to my attention that tapping the primary coil from the bottom turns, and heavily insulating the top turns, reduces flashover. (now gee, why didn't I think of that?) Good gap quenching is a must. Because the coupling is so much tighter in Magnifier systems, more strain is put on the main system spark gap. If ever there was a need for exotic spark gap systems this is it. Quench times must be low, low, low, in order to trap the maximum energy into the secondary driver. An un- quenched (closed) gap will allow energy in the secondary back into the primary/tank circuit. This must be prevented. In Colorado Springs, Tesla used a pair of air blast gaps in series with a massive rotary. He kept pushing his line frequency higher (he had a massive, variable speed alternator in the lab), increased his break rate (up to 50,000 bps) and kept the energy delivered per pulse down to a minimum. The reason he strove to keep the energy per break down was to prevent overloading his gaps. As energy per break (voltage * current) increases, quench times decrease and efficiency in the Magnifier drop off. The increase in the number of breaks per second allowed the total energy processed to climb to unheard of levels, with unheard of performance and efficiency. The next key point to building and operating a small to medium Tesla Magnifier is proper coil impedances in the secondary driver and extra coil. The extra coil must have a higher impedance than the secondary driver. The extra coil must be lower in resonate frequency. I have mentioned here that the 1/8th harmonic output of the secondary driver coil matching the natural 1/4 wave resonate frequency of the extra coil is the most efficient mode of Magnifier operation. This is true, but don't get bogged down with it. This system will work and fire (within reasonable limits) with any extra coil that has a higher impedance and inductance that the driver secondary. Let me give some tips. I have found that most high performance 1/4 wave secondary coils make lousy driver secondary coils in the Tesla Magnifier. The reason is the impedance and inductance are too high, and the 1/4 wave coil is not designed or constructed to handle high current outputs. 1/4 wave coils built per my instructions (posted here several times) are designed to produce excellent 1/4 wave voltage peaks, not 1/8th wave current. Your best bet is to wind a special coil for use as a driver. With this in mind what type of coil design would work best? Well my first decent driver coil was built for use as a 1/4 wave resonator, but it dropped into the role of a Magnifier driver without complaint; it had a nice low aspect ratio, and it was wound with heavy stranded wire... A good general purpose Magnifier secondary has a very low aspect ratio for good tight coupling over the entire winding length (say about 1.5:1). It is wound with heavy stranded insulated wire (say #18 or larger) to help carry heavy RF currents with lower losses. The frequency of the coil should not be too low, say in the area of 400 kHz for most medium systems. For the extra coil you want to pack a lot of inductance into a small unit volume, but not too much. You will end up with an amazingly short resonating coil if this is done properly. Use a 6" or 8" coil form with an aspect ratio a little over 2:1. For winding the coil use say #20 -#24 double Formvar magnet wire. The extra coil must be heavily top loaded with toroid discharger in order to produce really killer performance, as is the case when pumping a lot of energy through any magnet wire coil. The impedance in the bare extra coil must be higher than the driver coil by some margin, and the frequency of the extra coil should be brought down around 200 kHz by top loading the coil with discharger. The impedance of the driver must be low (heavy stranded wire spaced by insulation) while the impedance of the extra coil must be high (thin magnet wire, close wound turns) The tank circuit of the Magnifier must be tuned to the same frequency as the extra coil with discharger. Set the driver secondary inside the primary and run a transmission line some 6- 8' to the extra coil. The extra coil must be away from any field damping effects such as ground, large metal objects, other coils etc. It must be allowed to resonate as freely as possible. ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Date: 12-23-93 06:38 From: Brian Carling To: Joe Hayes Subj: Tubes ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ JH>Does anyone know a good source for buying 6KD6 tubes? JH>The old horizontal output tubes. Sources of Vacuum tubes ("valves") in the U.S. Antique Audio (512) 467-0304 5555 N. Lamar, Bldg. H-105 Austin, TX 78751 Tubes, parts, books, kits Antique Electronic Supply Co. (602) 820-5411 6221 S. Maple Avenue Tempe, AZ 85283 (Tubes & other components) Antique Radio Classified (508) 371-0512 Write for free sample. P.O. Box 802 Magazine. You'll find almost ANYTHING here Carlisle, MA 01741 for older radios, obscure parts, tubes etc. C & N Electronics (800) 421-9397 / (612) 429-9397 6104 Egg Lake Road FAX # (612) 429-0292 Hugo, MN 55038 Buy & sell tubes CeCo Communications (212) 646-6300 2115 Avenue X Brooklyn, NY 11235 (Vacuum tubes) Daily Electronics (206) 896-8856 / (800) 346-6667 10914 N.E. 39th Street Fax # (206) 896-5476 Vancouver, WA 98682 Tubes, all types. (CW paddles, keyers etc.) DH Distributors (316) 684-0050 P.O. Box 48623 Wichita, KS 67201 Tubes, radio, TV, industrial Electron Tube Enterprises (802) 879-0611 Box 311 Essex, VT 05451 Tubes Fair Radio Sales (419) 227-6573 1016 E. Eureka (419) 223-2196 FAX: (419) 227-1313 Box 1105 Parts, transformers, power supplies, Lima, OH 45802 Surplus and gov't surplus radios Fala Electronics (No number listed) send s.a.s.e. P.O. Box 1376-1 Milwaukee, WI 53201 Vacuum tubes Kirby No number listed 298 W. Carmel Drive Carmel, IN 46032 Tubes, new up to 90% off New Sensor Corp. (212) 529-0466 FAX: (212) 529-0486 133 Fifth Avenue (800) 633-5477 New York, NY 10003 Vacuum tubes galore! P.E.M. Tubes (916) 383-9107 7392 French Road Sacramento, CA 95828 Tubes, radio, TV, transmitting, CRT Lawrence Rauchwerger (217) 352-6195 1610 1/2, W. Union St Champaign, IL 61821 Tubes. S.A.S.E. list RF Parts (619) 744-0700 (0728) 1320 Grand Avenue (800) RF-PARTS or (800) 854-1927 to order. San Marcos, CA 92069 (RF power transistors & tubes) Steinmetz Electronics (219) 931-9316 7519 Maplewood Avenue Hammond, IN 46324 Tubes Tucker Surplus Sales (214) 340-0631 1717 Reserve St. Garland TX 75042 +1-800-527-4642 extension 135 Surplus radio & test equipment Turner Electronics No number listed 16701 Main Street Suite 121 Hesperia, CA 92345 Tubes, capacitors, S.A.S.E. list Unity Electronics P.O. Box 213 Elizabeth, NJ 07206 Vacuum tubes Vacuum Tube Industries Inc. (800) 528-5014 Ext. 74 P.O. Box 2009 (508) 584-4500 FAX: (508) 584-0096 Brockton, MA 02405 Rebuilt power amplifier tubes etc.