Date: 04-10-94 14:19 From: Richard Quick To: Jim Oliver Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Jim, Your two tapes were posted airmail on Friday, April 8. The post office here said it would take about a week to arrive in New Zealand, from there it is up to your customs and postal authorities as to deliverly time. I hope you enjoy the video, please post me a return letter to let me know you received them. Thank you, Richard Quick 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-25-94 15:42 From: Dave Halliday To: Richard Quick Subj: tesla and stuff... 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Hi Richard - this is a test message as well as a Tesla update. I am now receiving Fido from the satellite dish and this message is a part of one of my first up-load packets... We'll see what happens... Anyway, things have been incredibly busy at work so I havn't had time to finish the coil as yet. I am looking for another employee to help with the load... I have the controller almost finished - need to refine the software a bit, right now it is just on/off and increment/ decrement voltage and I want to add safety interlocks and timers. As for hardware, I just need to do the primary and the base. I have a bunch of plexiglass scraps also although I am using a varnished plywood base, I will be supporting everything up off of it with strips of 1/4" plexi. The powerstats are wired into the main breaker panel and they run fine! I will keep you posted - TTYL - Dave � Overcome by jealousy, Data dismembers the Energizer Bunny ! Origin: Grey Matter * Seattle, WA * (206) 528-1941 (1:343/210. (1:343/210) 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-25-94 16:09 From: Richard Quick To: Dave Mcknight Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Dave your video tape was posted today. I hope you are satisfied with the quality and content. If you have any questions or comments please feel free to post me here or mail a letter. I would be more than happy to respond. Thanks again. 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-26-94 16:14 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� DH> Hi Richard - this is a test message as well as a Tesla DH> update. Receiving you loud and clear! DH> I am now receiving Fido from the satellite dish and this DH> message is a part of one of my first up-load packets... DH> We'll see what happens... Looks to me like it is working fine. DH> Anyway, things have been incredibly busy at work... I know that feeling, sometimes you feel like there is no time to wipe (your data disks ya know!) DH> I have the controller almost finished - need to refine the DH> software a bit, Software? Computer controlled? I would like to hear more. DH> right now it is just on/off and increment/decrement voltage DH> and I want to add safety interlocks and timers. That should be about all you need to start firing with a few neons and a six inch coil. The benefit of moving slow at this point is that the time allows your caps to fully soak up oil. DH> As for hardware, I just need to do the primary and the base. One good marathon session here should get you a primary that can be jury rigged enough to fire. Figure on making some adjustments with a juried primary coil (maybe nylon wire ties holding things in place) and then hardening it down after a few test runs. DH> The powerstats are wired into the main breaker panel and DH> they run fine! Sounds like your closer then perhaps you think. No current limiting is required with a power up of neon xfrmr cores, a simple deadman switch run to a current relay will provide a reasonable safety interlock for the power feeds, you may add the timer and additional interlocks at a later date when you are satisfied that the basic setup (line in to discharge terminal) is working. I have found it best to start the controller wiring simple, then upgrade to the desired complexity. Remember the more complex the unit is at startup, the more bugs are in the system! 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-27-94 20:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Dave, I thought I would take a minute to cover some aspects of RF choking on the feed lines to the Tesla Tank circuit. I will refer you to vol. 13, #2, page 6 of the Tesla Coil Builders Association publication NEWS for a start. Since others will be reading this, and will not have access to this publication, I will reproduce the circuit diagram below. PC1 X1 RFC 1A RFC 2A 컴컴컴컴쩡컴컴커붚컴컴컴程程粘컴쩡컴쿤程程컴�> TO TESLA TANK 컨� )�( � 컫� )�( � � )�( O .픔컴� )�( .픔컴훟 SAFETY GAP � )�( O 컨� )�( � 컫� )�( � 컴컴컴컴좔컴컴켸봉컴컴컴UUUUU컴컨컴컴훃UUUU컴�> TO TESLA TANK PC2 RFC 1B RFC 2B "Radio Frequency Chokes RFC 1A and 1B are wound with about 70 turns on a 1" cylinder (PVC, plastic, etc.). RFC 2A and 2B are wound with around 20 turns on a similar form. The size of the wire is not critical as long as the wire is capable of carrying the rated current." "Protective Capacitors PC1 and PC2 are not critical and can be rated in the vicinity of .5 to 2 microfarads. Use a voltage rating as high as possible. The usual 400-600 volt capacitors will not withstand kickbacks for very long. I prefer capacitors with ratings of from 2500 to 5000 (or higher) volts" The above is quoted from the article, X1 is of course the high voltage step up transformer that supplies the Tesla Tank. I will note that this circuit is the bare minimum protection required, and that this is only adequate for small (6") coils running under 1.5 KVA. Even the author, Harry Goldman, admits that this RF protection circuit does not eliminate, but only reduces the RF and kickback problem. Note his statement that the low voltage line PC (Protective Capacitors) capacitors (PC1 & PC2) need a rating of 2500 volts or higher. These capacitors are across the 120 or 240 volt 60 cycle line!!!! Imagine what voltage spikes are appearing in the house or shop supply line if 400-600 protective capacitors are routinely failing. Obviously the problem needs some more attention. Please note the modifications to the above circuit in my recommended circuit below. �------� | | X1 RFC 1A 컴|컴컴컴|컴컴커붚컴컴컴쩡컴컴컴컫컴컴程程粘컴> TO TESLA TANK | | )�( � � | | )�( � � | | )�( BC1 컨� O | LF1 쳐�. )�( 컫� o컴�. SAFETY GAP | | )�( � O | | )�( � � | | )�( � � 컴|컴컴컴|컴컴켸봉컴컴컴좔컴컴컴컨컴컴훃UUUU컴�> TO TESLA TANK | | � RFC 1B �------� 賈� grnd LF1 is a commercial heavy duty line filter wired in reverse. Where current throughputs are high I use several in parallel. Quality commercial line filters employ iron powder chokes, as well as the "PC" capacitors of the circuit at the top of this post. The Line Filters I use also have RF choke coils in the ground path; the ground wire can be run reversed (it is neutral) and can be used to trap stray RF, preventing ground path contamination to the 60 cycle breaker box. I should note that I use a minimum of two independent grounds. The core of X1, and everything to the right of X1 in this diagram, is grounded separately to a heavy, dedicated, RF ground. This heavy RF ground is also used to ground the base of the Tesla secondary. Note that the core of X1 is grounded in this diagram, where the top diagram shows the core floating ungrounded. I believe this was an oversight of Mr. Goldman's. BC1 is a Bypass Capacitor. I use high voltage barium titanate doorknobs, with stacks of four or more in series. A typical rating for a single cap would be .003 microfarad @ 30 KVDC, and using four of these caps in series I get .0007 microfarads at 120 KVDC. Since the AC rating is about half the DC rating on these type capacitors, figure a series stack of four will withstand a kickback of 50-60 KVAC in this use. Where center tap ground type xfrmrs are used for X1 (such as neon sign cores) BC1 must be divided into two units, and the center of the stack must be grounded with the xfrmr core (see the arrange- ment of PC1 and PC2 in the top most diagram). Use no more than .0008 or so microfarads per side, as too large a bypass capaci- tance will create an oscillating current in the high voltage windings on your step up xfrmr that will cause the xfrmr to fail. RFC 1A and RFC 1B are about 15-20 turns (minimum) of insulated wire on a large iron powder core. I use 2" diameter iron powder toroids to wind these chokes. I have found that the RF and Kickback protection of the circuit using bypass capacitors and iron powder (as opposed to air core) RF chokes is much better than the simpler circuit recommended by Mr. Goldman. If you are running a small tabletop Tesla coil, then Mr. Goldman's circuit is probably all you need. But if you are running, or intend to run, more than 1.5 KVA out of your power supply; look carefully at the circuit I have outlined. Remember... Over 1.5 KVA and the kickbacks are sounding like high powered rifle shots at the safety gap. They will "light up your life" if not properly contained and grounded. 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-27-94 08:56 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� RQ|Dave I just thought I would stick my nose in and see if you |were still putting your Tesla project together. I am actually only about ten hours away from "first light" I have the basics of the control circuitry together, I want to refine it some more but since it is in an EPROM, I can do that at any time. The powerstat is wired into my main panel at home. Basically, the only things remaining are: Building the primary and the base - I have all the supplies and although I will be using varnished plywood, I have a bunch of plexiglass strips so I will put the primary coils a couple inches off the plywood. Wiring - this should be fairly simple - I got some surplus Coax from Boeing ( as well as picking up a good quantity of teflon tubing for good measure! ) I still need to build the transformer protection circuitry. There is a good amateur radio place in town but all of their experience with RF shielding has been in the MHz region so I will probably just call Amidon or Palomar and have them recommend a ferrite material for the torroids. I also need to build the capacitive hat - have some of the stuff - found a really good commercial heating supply place and bought the Al foil tape there ( as well as 100' of 3/8th refrigeration tubing for the primary coil ) After that, it should be just a matter of tuning the puppy up ( *MORE* fun and games!!! ), warning the neighbors and letting 'er rip! I will keep you posted - also, I have been taking still and video photos during the construction so I have a nice documentation of the whole process. BTW - what is happening with you? Hadn't seen any posts from you for some time either... TTYL - Dave � Let the meek inherit the Earth... I want the stars! ! Origin: Grey Matter * Seattle, WA * (206) 528-1941 (1:343/210. (1:343/210) 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-27-94 20:55 From: Richard Quick To: Don Peruski Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 Don, I caught Dave McKnight's reply to your question about Tesla Coils. If you are at all interested in the subject I would be very much interested in hearing from you. Dave Halliday who posts in this conference is working on a Tesla coil input power controller and has wound a couple of smaller coils. I myself have operating systems that include: small Tesla Magnifiers, neon powered coils up to 3 KVA, and larger coils powered by utility distribution xfrmrs (pole "pigs") wired in reverse. My 10" diameter secondary coil sports a 40" diameter toroid discharge terminal, has an input power of 10 KVA (20 KVAC @ 1/2 amp), and produces 11-15 foot sparks (point to point in a straight line as measured by a tape measure). If you are interested in learning more, or have information to share, please post me. I have a video tape of some of my coiling activities, including my big coil running flat out. The video also has details of the power controller, spark gaps, RF choking, and an interesting section where I wire up the pole pig for a 10 KVA Jacobs Ladder. Nobody who has seen this stuff in person, or on video, has been dissapointed. Terms for the tape are as follows: Send me a blank, high quality VHS video cassette. Include a self addressed, first class postage pre-paid mailer, and $10.00 to cover my time and defray my production costs (I had to buy a second VCR to make copies). In return I will send you a full two hour, SP recorded, one off master video tape of the highest quality. When I offer the tape I must include the disclaimer: The experiments featured in the video are quite dangerous. The equipment and setups are absolutely lethal. I cannot be responsible for the safety of anyone who reproduces, or attempts to reproduce, any of the experiments or equipment I feature on the tape. I have sent out several copies of the tape to people in this conference if you require a reference. Dave McKnight just received his copy this week if I am not mistaken. If you are interested in more info, you may contact me here, or write: Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-27-94 20:25 From: Richard Quick To: Dave Mcknight Subj: Something fun 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 -=> Sez Dave Mcknight to Don Peruski <=- DP>Anyone out there ever make a Tesla Coil?? DM> Talk to Richard Quick - absolute expert on Tesla. Thanks for the vote of confidence. Really appreciated. You should have your video tape showing some of my work by the time you get this. I would like to hear your thoughts about the coils, Jacobs Ladder, etc.. 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-28-94 07:42 From: Dave Mcknight To: Richard Quick Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 RQ>Dave your video tape was posted today. I hope you are >satisfied with the quality and content. RQ>If you have any questions or comments please feel free to post >me here or mail a letter. I would be more than happy to >respond. RQ>Thanks again. Thank YOU Richard. I've been following this thread for awhile, so I've already learned quite a bit from you. I've already built a desktop unit of my own, and I am really looking forward to seeing the tape of your "monster" unit in action. She kept saying I didn't listen to her, or something. ! Origin: The Computer Room-Pickerington, Oh (614)861-8377 (1:226/110) 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-28-94 22:22 From: Richard Quick To: Bruce Kingsbury Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� -=> Sez Bruce Kingsbury to Jim Oliver <=- JO> The videos are excellent. I also have a complete record of JO> the Tesla Coil mail that has been posted in ELECTRONICS plus JO> some info that hasn't. I can supply you with copies if you JO> send me return postage and address etc. Humm, looks like you guys are going to be burning sparks soon! BK> Is that hardcopy or still on disk? Trust me, it is still on disk. There is enough on that disk to print out a nice thick book! BK> Anyway, I'm sure I'm not the only one in NZ that's BK> interested in that video! (So my videos are going to be making the rounds in New Zealand!) I guess I can't really complain about you guys making copies of my tapes, being halfway around the world and all. Enjoy the info, and I hope you pick up some coiling tips. But please let me know what you think when you get your copy. I sent Jim four hours of video (two tapes), if you are only going to get two hours from him (one tape), be sure to ask for the last two hours worth, with my big coil cooking up the backyard. The first tape I sent him clearly shows that the mystery of the Tesla Magnifier has been solved, and I have working systems in my lab. 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-28-94 22:47 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� -=> Sez Dave Halliday to Richard Quick <=- DH> I have been completely swamped at work these last few months DH> so I have just been going home.... then going to sleep. Ditto DH> Anyway, I am actually only about ten hours away from "first DH> light" It will take twenty hours if you figure ten... At least that is the way it seems to work for me. But your right, one good marathon session should have you testing the switch! Get a good nights sleep the night before, and plan on staying up way late! DH> I have the basics of the control circuitry together, I want DH> to refine it some more but since it is in an EPROM, I can do DH> that at any time. I would really be interested in hearing more about this computerized power controller. DH> Basically, the only things remaining are: DH> Building the primary and the base... and... DH> I still need to build the transformer protection DH> circuitry. There is a good amateur radio place in town but DH> all of their experience with RF shielding has been in the DH> MHz region so I will probably just call Amidon or Palomar DH> and have them recommend a ferrite material for the toroids. I just sent you some detailed info on the xfrmr RF protection circuits yesterday, with references to the TCBA NEWS Q&A column on the subject. If you need some more help with this just let me know. DH> I also need to build the capacitive hat - have some of the DH> stuff - found a really good commercial heating supply place DH> and bought the Al foil tape there ( as well as 100' of 3/8th DH> refrigeration tubing for the primary coil ) You are smart to build your own toroid discharger. You save some big bucks with the construction techniques I have sent along, and as you look at the video of the 40" toroid on my big coil you will see it really turns out looking sharp, as well as perfectly functional. Construction time for my 40" toroid was about 4 hrs. DH> I will keep you posted - also, I have been taking still and DH> video photos during the construction so I have a nice DH> documentation of the whole process. Absolutely cool! Good documentation on this stuff is, as you know, rare. DH> BTW - what is happening with you? Hadn't seen any posts DH> from you for some time either... Well it's the same as you outlined to me at the start of your post. But I have been involved in some correspondence with some guys in New Zealand that were getting my outgoing posts in this conference, but were not able to reply. They have been writing me airmail. Jim Oliver just received two of my videos via inter- national air, and I just saw the first of his replies here last week, so they must be getting out now. Look for some ECHOmail posting back and forth from the lands "down under" about this thread, and increased posting from your truly as the inevitable questions and remarks come topside! 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-27-94 16:56 From: Brad Chaucer To: Richard Quick Subj: Re: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� RQ> I am really glad you enjoyed the Tesla videos, I worked RQ> very herd to get the best possible material on tape, and RQ> really just scratched the surface. I remember you mentioning/offering a video tape of some Tesla coils you had made. Could you please repost the cost/contents, Thanks Regards, Brad Chaucer ! Origin: The Dosadi Experiment (1:142/906) 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-29-94 18:03 From: Richard Quick To: Dave Mcknight Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 RQ>Dave your video tape was posted today. DM> Thank YOU Richard. I've been following this thread for DM> awhile, so I've already learned quite a bit from you. How long have you been tuning in, and what are your main interests/problems with Tesla Coils? My video tape is skewed perhaps to the majority interest... POWER (which I freely admit being a sucker for), but it only covers a tiny fraction of the coiling work/experimentation that I have conducted. DM> I've already built a desktop unit of my own, How about taking some time and giving us the basic specs of your desktop system: Power supply, capacitor type and size, secondary coil dimensions and the like. DM> and I am really looking forward to seeing the tape of your DM> "monster" unit in action. Well, I am almost sure that you are watching the video with your jaw in your lap as I am writing this post. If not, let me know in a hurry, but I don't think you will be disappointed. I hope it sparks your interest! 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-29-94 12:22 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil 1/2 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� RQ|Dave, Hi Richard! How's it going? RQ|I thought I would take a minute to cover some aspects of RF |choking on the feed lines to the Tesla Tank circuit. I will |refer you to vol. 13, #2, page 6 of the Tesla Coil Builders |Association publication NEWS for a start. Since others will be |reading this, and will not have access to this publication, |I will reproduce the circuit diagram below. I have it in front of me right now - also, I went ahead and got some reprints of volumes 10, 11 and 12 - great stuff! RQ|Please note the modifications to the above circuit in my |recommended circuit below. RQ| �------� | | | X1 RFC 1A |컴|컴컴컴|컴컴커붚컴컴컴쩡컴컴컴컫컴컴程程粘컴> TO TESLA TANK | | | )�( � � | | | )�( � � | | | )�( BC1 컨� O | | LF1 쳐�. )�( 컫� o컴�. SAFETY GAP | | | )�( � O | | | )�( � � | | | )�( � � |컴|컴컴컴|컴컴켸봉컴컴컴좔컴컴컴컨컴컴훃UUUU컴�> TO TESLA TANK | | | � RFC 1B | �------� 賈� | grnd RQ|LF1 is a commercial heavy duty line filter wired in reverse. OK - As you might remember, I scored a 60 amp filter - the thing weighs about thirty pounds and is in a metal case with large ( 1/4" dia ) lug terminals on each end. If that doesn't stop it, nothing will! |ground path; the ground wire can be run reversed (it is |neutral) and can be used to trap stray RF, preventing ground |path contamination to the 60 cycle breaker box. I should note |that I I was planning to do that with the third line - it was for some three-phase equipment so each of the lines is independent and floating. |use a minimum of two independent grounds. The core of X1, and |everything to the right of X1 in this diagram, is grounded |separately to a heavy, dedicated, RF ground. This heavy RF |ground is also used to ground the base of the Tesla secondary. Got it - the RF ground is in place - three ten-foot lengths of 1/2" copper pipe sunk into my front yard. I took out the grass and put in some "interesting" landscaping a few years ago so I don't have to worry about mowing around them. I have some 1" heavy copper braid that I will be using to connect them together ( still thinking of the best way for that - I will start with stainless hose clamps and see what I can work out from there. RQ|Note that the core of X1 is grounded in this diagram, where |the top diagram shows the core floating ungrounded. I believe |this was an oversight of Mr. Goldman's. RQ|BC1 is a Bypass Capacitor. I use high voltage barium titanate |doorknobs, with stacks of four or more in series. A typical OK - I was going to ask if you had a good source for them. I just got the current Fair Radio catalog and was quite disappointed in their high prices for stuff that was several generations old... They do have some "doorknob" style caps but they are more in the 1,000pF / 5KV rating and cost $8 each... |KVDC. Since the AC rating is about half the DC rating on these |type capacitors, figure a series stack of four will withstand |a kickback of 50-60 KVAC in this use. RQ|Where center tap ground type xfrmrs are used for X1 (such as |neon sign cores) BC1 must be divided into two units, and the |center of the stack must be grounded with the xfrmr core (see |the arrangement of PC1 and PC2 in the top most diagram). Use |no more than .0008 or so microfarads per side, as too large a |bypass capacitance will create an oscillating current in the |high voltage windings on your step up xfrmr that will cause |the xfrmr to fail. OK - never thought of that but it makes a lot of sense! You are trying to tune the coil, not your neons... RQ|RFC 1A and RFC 1B are about 15-20 turns (minimum) of insulated |wire on a large iron powder core. I use 2" diameter iron |powder toroids to wind these chokes. OK - I will be calling Amidon and Palomar to see who has better material for the toroids. The stuff for sale at the amateur radio store near me was more for 2MHz on up. RQ|I have found that the RF and Kickback protection of the |circuit using bypass capacitors and iron powder (as opposed to |air core) This is the design that I was planning on using anyway. |Remember... Over 1.5 KVA and the kickbacks are sounding like |high powered rifle shots at the safety gap. They will "light |up your life" if not properly contained and grounded. Wow! ! Origin: Grey Matter * Seattle, WA * (206) 528-1941 (1:343/210. (1:343/210) 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-30-94 13:28 From: Richard Quick To: Brad Chaucer Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 BC> I remember you mentioning/offering a video tape of some BC> Tesla coils you had made. Could you please repost the BC> cost/contents... Thanks OK, lets see... The video tape is a brief look at some standard 1/4 wave Tesla work, though some people have requested, and have received, videos that include my introductory work of the three coil Tesla Magnifier system. The basic tape that is most requested is two hours in length, SP recorded on VHS format. It is a high quality, one-off, master. The tape opens with my 10KVA (10,000 watt) "pole pig" or power distribution transformer wired in reverse. This xfrmr has two high voltage bushings and is made to step down 22,890 volts for 120-240 use. I use a power control cabinet (ganged variacs with filters and switching equipment) wired in series with an arc welder (to limit the current). The power cabinet and wiring are detailed. Using the cabinet/current limiter I am able feed a current limited controlled voltage (0-280 volts, 9-60 amps) into the low voltage windings of the pole pig. I bolt two 3/8" soft copper pipe "rails" to the high voltage bushings on the xfrmr, and fire a Jacobs Ladder at up to 8000 watts at 20,000 volts. As the xfrmr growls, some of the resultant arcs threaten to catch the garage ceiling joists on fire. I then construct a high voltage RF filter board and test it across the high voltage side of the xfrmr system. Then I set up my large coil for some low power tuning and testing. This coil is 10-3/4" in diameter, with a winding of single layer #21 magnet wire. The coil has over 900 turns, and the length of the winding is 32 inches. The coil is topped off with a 20" diameter toroid discharge terminal. The primary coil (100' of 1/2 od soft copper water pipe) is set up with two .1 uf commercial pulse discharging capacitors (rated at 45,000 volts AC) in series, and we excite the circuit with a simple static spark gap and a couple of 9000 volt 30 ma neon sign xfrmrs. The entire ceiling network of florescent lamps (and even disconnected stored bulbs) glow from the radiant energy. No spark yet... But I grab a hard copper water pipe in my bare hands, and standing on a plank, draw a foot of hot spark from the discharge terminal. Next we clear out some garage space and hook the coil up to the pig for some "run in". We are using a fixed speed rotary spark gap and the coil really wails with 60-70 inch sparks indoors, again threatening to ignite the ceiling joists. We cut to some small coils here as I develop a static gap system that uses a shop vacuum motor to quench (stretch and cool) the hot primary arc. I fire using homemade capacitors and a pair of 15,000 volt 30 ma neons. Once I am satisfied with the new gaps, we place them in series with the rotary gap on the big coil, and get better performance. The new gap system removes the overload from the rotary. Again the ceiling threatens the catch fire as sparks from the coil completely penetrate the wooden joists as if they were paper. Next I move the coil outside and increase the input power by opening up the current limiter and letting it rip. The new gap system holds up, and thick white arcs 8-9 feet long strike everything within reach. The spark gaps light up the entire back drive. The coil really howls! Lots of current in the continuous output... These are not Van de Graff discharges!!! The spark is still not long enough for me! I build a new discharge terminal out of flexible plastic drain pipe and aluminum foil tape. We set the coil up again in the back drive, retune the system for the new discharger, and open it up again. The discharger is mounted a little too close to the coil in this test series, and the spark is caught up in the primary/secondary field flux. Arcs to the grounded rail protecting the primary and tank circuit are white hot, thick as a man's leg, and 4-5 feet long. The power does drive a few long strikes away from the system. The photographer moves up, then moves way back as the discharge nearly strikes the camcorder. I really let the coil burn; 8-10 KVA input in several runs of 3-5 minutes. We record and measure point to point strikes from 7.5 to 11 feet. Other sparks completely leave the field of view of the camcorder, and exit the screen 15 feet from the coil discharger. I end the tape with freeze frame and slow motion shots. Giant sparks are caught by the camera walking the ground all around the system (100 to 132 inch strikes), the basketball net is hit with a full current strike (90"), the garage is struck and a corona cloud lights up the brickwork (117" strike), etc... Terms for a copy of the video are as follows: Send me a blank high quality VHS video cassette. Include a first class postage pre-paid self addressed mailer, and $10.00. I will copy the video onto your tape, pop it into your mailer, and send it back. I must include the disclaimer: This work is dangerous. All of the equipment and experiments featured have lethal potentials. I cannot be responsible for the safety of anyone who reproduces, or attempts to reproduce any of the equipment or experiments I feature on the video. My address is: Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale, Missouri, 63122, USA 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� Date: 04-30-94 14:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil 컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴 DH> Hi Richard! How's it going? Better. It's the weekend! I edited out some stuff here, but we were discussing the Tesla RF dedicated ground... DH> Got it - the RF ground is in place - three ten-foot lengths DH> of 1/2" copper pipe sunk into my front yard. I have some 1" DH> heavy copper braid that I will be using to connect them DH> together ( still thinking of the best way for that - I will DH> start with stainless hose clamps and see what I can work out DH> from there. This should work fine. Trench about 4" down and run the braid below the sod. Hose clamps are excellent, I use them too, but you might want to think about getting out the blowtorch and silver soldering the connections. Just a suggestion, I do both. Now we are talking about HV RF choke/filters to protect the step up xfrmr from the kickback of the Tesla Tank circuit... RQ> BC1 is a Bypass Capacitor. I use high voltage barium RQ> titanate doorknobs, with stacks of four or more in series. DH> OK - I was going to ask if you had a good source for them. Gary Legel has them for $6.00 each for the ones I use: Sprague .003 ufd @ 30 KVDC. Write Gary at: 1306 Sheppard Dr. Fullerton CA. 92631. Dan Smith also has these same caps: Dan Smith, 8904 Cypress, Cotati, CA. 94931 RQ> Use no more than .0008 or so microfarads per side, as too RQ> large a bypass capacitance will create an oscillating RQ> current in the high voltage windings on your step up xfrmr RQ> that will cause the xfrmr to fail. DH> OK - never thought of that but it makes a lot of sense! You DH> are trying to tune the coil, not your neons... Yup, I burned 1/4" holes through a 1" braided ground strap because I used to much bypass capacitance. The strap welded itself to the case of my neon bank where it was connected and at incidental contact points. .00015 ufd was all it took to set up the high current ocsillation between the xfrmr windings and the ground. This is another good reason for using a DEDICATED HEAVY GROUND for the xfrmr core, safety gap, and coil.