brandenberg@star.dec.com (bleakness...desolation...plastic forks...) (12/09/86)
> Matt Giger (tektronix!reed!shadow) asks about tesla coils...
A tesla coil is simply a series resonant circuit with an
autotransformer's primary winding used as the inductive
component. Near resonance, the circuit's "Q" produces a
substantial voltage across the transformer. As for
references, the University of Missouri at Kansas City
once had a copy of Tesla's laboratory notes prior to his
work in Colorado (available on loan). I also have plans
for a tesla coil. These were purchased from an outfit
called Huntington Electronics, Inc. ( Box 9 Huntington Station,
Shelton, Conn 06486 [copyright 1965] ) sometime in the late
'70's. The plans are for a six foot tesla coil capable of
three foot discharges. The difficulty in constructing such
a coil is the prevention of dielectric breakdown and the
generation of a high-voltage, high-current variable frequency
power source. If you're interested in building a less
ambitious coil, my description, basic network synthesis, and
engineering "common sense" will suffice. If you're simply
interested in the history, you will have some work ahead of
you: Tesla's notes from his Colorado Lab were (as I recall)
seized by the Government at the time of his death and those
that weren't given to the Czechoslovakian Government are
still sealed away.
Monty Brandenberghes@ecsvax.UUCP (12/09/86)
[this line eater message defeats the 50% rule] In article <6824@decwrl.DEC.COM>, brandenberg@star.dec.com > > > Matt Giger (tektronix!reed!shadow) asks about tesla coils... > ... > As for > references, the University of Missouri at Kansas City > once had a copy of Tesla's laboratory notes prior to his > work in Colorado (available on loan). > ... Tesla's notes from his Colorado Lab were (as I recall) > seized by the Government at the time of his death and those > that weren't given to the Czechoslovakian Government are > still sealed away. > > Monty Brandenberg When I visited the Museum of Natural History in Denver they had several books on Tesla. I bought "My Inventions", the autobiography of Nikola Tesla (published by Hart Brothers in 1982), and it is quite readable, but doesn't give much technical explanation. They also had a large book (as I remember it was 8 1/2 x 11" and about 1" thick) which was mostly photocopied laboratory notebooks from experiments in his Colorado Springs Lab. You might get some help from the museum bookstore. --henry schaffer n c state univ
ewiles@netxcom.UUCP (Edwin Wiles) (12/10/86)
In article <6824@decwrl.DEC.COM> brandenberg@star.dec.com (Monty Brandenberg) writes: ...edited... > If you're simply >interested in the history, you will have some work ahead of >you: Tesla's notes from his Colorado Lab were (as I recall) >seized by the Government at the time of his death and those >that weren't given to the Czechoslovakian Government are >still sealed away. > > Monty Brandenberg Would anyone know WHY the government would do this? I don't remember anything about Tesla coils or his form of 'broadcast' power that is especially dangerous, or useful in war. As for the potential of using it for broadcast power, I remember that either it didn't work too well, or there was no way to keep unauthorized persons from tapping into the supply without paying. (Not sure which it was, might be both!) -- Edwin Wiles Net Express, Inc. 1953 Gallows Rd. Suite 300 Vienna, VA 22180
mwm@cuuxb.UUCP (12/10/86)
In article <221@netxcom.UUCP> ewiles@netxcom.UUCP (Edwin Wiles) writes: >In article <6824@decwrl.DEC.COM> > brandenberg@star.dec.com (Monty Brandenberg) writes: >...edited... >> If you're simply >>interested in the history, you will have some work ahead of >>you: Tesla's notes from his Colorado Lab were (as I recall) >>seized by the Government at the time of his death and those >>that weren't given to the Czechoslovakian Government are >>still sealed away. >> >> Monty Brandenberg > >Would anyone know WHY the government would do this? I don't remember >anything about Tesla coils or his form of 'broadcast' power that is >especially dangerous, or useful in war. As for the potential of using >it for broadcast power, I remember that either it didn't work too well, >or there was no way to keep unauthorized persons from tapping into the >supply without paying. (Not sure which it was, might be both!) >-- > Edwin Wiles I seem to recall hearing the story of the time Tesla built a gadget for a party that was designed to find the resonant frequency of the main crossbeam supporting his house -- the Idea was to have the whole house vibrating by the time the party was in full swing. It apparently worked a little too well, and found the resonant frequency of the rock vein his house was sitting on, and knocked down the fire house accross the street. Supposedly he destroyed that particular part of his notes; but these and other gadgets he designed could potentially have been used for weapons. Of course, I don't know how accurate the story is, I heard it about 3rd hand. -- Marc Mengel "All that is gold does not glitter ...!ihnp4!cuuxb!mwm Not all those who wander are lost The old that is strong does not whither Deep roots are not reached by the frost" -- J.R.R Tolkein
brian@sdcsvax.UCSD.EDU (Brian Kantor) (12/11/86)
Back about 1963, Popular Electronics magazine had some really nice Tesla coils in a pair of companion articles called "Big TC" and "Little TC". We built them in high school electric shop, using a lathe to wind the coil on Big TC. They worked really GREAT! Maybe your library has back issues (microfilm, perhaps)? Especially good was connecting the top of the Big TC coil to the doorknob of the classroom door - so that anybody attempting to come in drew a big arc to his fingers. Worked especially well with the principal. Yes, I'm still alive. Brian Kantor UC San Diego decvax\ brian@sdcsvax.ucsd.edu ihnp4 >--- sdcsvax --- brian ucbvax/ Kantor@Nosc "There is more harmony in films than in life." - Francois Truffaut
ken@argus.UUCP (Kenneth Ng) (12/12/86)
In article <221@netxcom.UUCP>, ewiles@netxcom.UUCP (Edwin Wiles) writes: > In article <6824@decwrl.DEC.COM> > brandenberg@star.dec.com (Monty Brandenberg) writes: > ...edited... > > If you're simply > >interested in the history, you will have some work ahead of > >you: Tesla's notes from his Colorado Lab were (as I recall) > >seized by the Government at the time of his death and those > >that weren't given to the Czechoslovakian Government are > >still sealed away. > > Monty Brandenberg > Would anyone know WHY the government would do this? I don't remember > anything about Tesla coils or his form of 'broadcast' power that is > especially dangerous, or useful in war. As for the potential of using > it for broadcast power, I remember that either it didn't work too well, > or there was no way to keep unauthorized persons from tapping into the > supply without paying. (Not sure which it was, might be both!) Read the New York times around the 1950's. I forgot the date, but sometime around then he proposed construction of a "death ray" that could knock airplanes from sky, and destroy huge armies easily. It kinda sounds like todays SDI program. > > Edwin Wiles > Net Express, Inc. > 1953 Gallows Rd. Suite 300 > Vienna, VA 22180 -- Kenneth Ng: Post office: NJIT - CCCC, Newark New Jersey 07102 uucp !ihnp4!allegra!bellcore!argus!ken *** WARNING: NOT ken@bellcore.uucp *** !psuvax1!cmcl2!ciap!andromeda!argus!ken bitnet(prefered) ken@orion.bitnet Kirk (about Spock): "He took too much LDS in the 60s"
keithd@cadovax.UUCP (Keith Doyle) (12/12/86)
In article <221@netxcom.UUCP> ewiles@netxcom.UUCP (Edwin Wiles) writes: >> Tesla's notes from his Colorado Lab were (as I recall) >>seized by the Government at the time of his death and those >>that weren't given to the Czechoslovakian Government are >>still sealed away. >> >Would anyone know WHY the government would do this? I don't remember >anything about Tesla coils or his form of 'broadcast' power that is >especially dangerous, or useful in war. As for the potential of using >it for broadcast power, I remember that either it didn't work too well, >or there was no way to keep unauthorized persons from tapping into the >supply without paying. (Not sure which it was, might be both!) 'Broadcast' power was only ONE of many, many, inventions that Tesla was working on. There were rumors of some kind of 'death ray' type technology that were never substantiated, as well as various other ideas that I suppose could be applied in wartime. In addition, 'broadcast' power could possibly have an effect of a Radio blackout, a powerful enough Tesla power transmitter might be designed that would have the effect of generating enough noise worldwide that would make radio communications difficult. It is interesting to note, that Tesla, recently credited with the invention of radio (rather than the previously believed Marconi) lived at a time and with appropriate knowledge to make minute measurements on the 'background' radio emmisions of the Earth. You may have heard the radio transmissions from Saturn picked up by Voyager. The Earth emits radio noise too, but unfortunately, we could never now get all the radio and TV stations, and CB radios to SHUT UP long enough to make much in the way of measurements of the Earths background emissions. From such measurments, and from observations of lightning activity at Colorado Springs (something like the most electrically active place on the face of the Earth), he deduced the resonant frequency of the Earth itself (I don't remember what it is exactly, but somewhere between 0 and 1 hertz). Using this knowledge, he designed his 'power without wires' system, that may have worked effectively by inducing the Earth's magnetosphere into resonance. With such a system, one could sink an antenna into the ground anywhere on the surface of the Earth, and tap into this source of power. Or at least so Tesla thought. Whether or not this scheme would actually work, we may never know. It's kind of too late now, as it is probably incompatible with our present use of radio frequency transmissions, as such a power transmission system would most likely wreak havoc on radio and T.V. all over the world. It is certain that Tesla was convinced of its viability, though his financial patron J. P. Morgan pulled the plug, because there was no economic advantage to 'free' power (and how do you 'meter' peoples use of power, when all they have to do is sink a simple antenna?). Not only that, it is not clear in my mind that enough 'antennas' tapping into this 'seemingly limitless' source of 'free' energy, wouldn't actually tax the 'exiteing circuit' i.e. the Tesla coil driving the resonant tank circuit (the Earth). But, it is fun to think about. I wonder if there will ever be a human being on this earth who has the kind of understanding of 'resonance' that Tesla must have had. He demonstrated the ability to virtually raze buildings to the ground with a small tapping device that would cause the resonance to build up in a building to the point of collapse. How he knew where to 'tap' on a building, and at what frequency is beyond me, but it is sure interesting to think about such things. For more information on Nikola Tesla, read 'Man out of Time' by Margaret Cheney one of the better Tesla biographies, (and perhaps the only one still in print). It recounts the 'war' between Tesla and Edison over AC vs DC power, (Edison publically electrocuted various animals with AC to show how *dangerous* it was, including dogs, a horse and an ELEPHANT! {I've seen the elephant on film}) and various anecdotes involving his friendship with Samuel Clemens. Keith Doyle # {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd # cadovax!keithd@ucla-locus.arpa
edhall@randvax.UUCP (Ed Hall) (12/14/86)
In article <2293@sdcsvax.UCSD.EDU> brian@sdcsvax.UUCP (Brian Kantor) writes: >Especially good was connecting the top of the Big TC coil to the >doorknob of the classroom door - so that anybody attempting to come in >drew a big arc to his fingers. Worked especially well with the >principal. > >Yes, I'm still alive. But is the principal? :-) -Ed
sewilco@mecc.UUCP (Scot E. Wilcoxon) (12/15/86)
In article <1254@cadovax.UUCP> keithd@cadovax.UUCP (Keith Doyle) writes: >Using this knowledge, he designed his 'power without wires' system, that ... >Whether or not this scheme would actually work, we may never know. It's >kind of too late now, as it is probably incompatible with our present use >of radio frequency transmissions, as such a power transmission system ... It also might be incompatible with the grounded metal-frame buildings and grounded utility poles (telephone, as well as the power grid). -- Scot E. Wilcoxon Minn Ed Comp Corp {quest,dayton,meccts}!mecc!sewilco (612)481-3507 sewilco@MECC.COM ihnp4!meccts!mecc!sewilco "How do you feel?"
levy@ttrdc.UUCP (Daniel R. Levy) (12/16/86)
In article <749@randvax.UUCP>, edhall@randvax.UUCP writes: >In article <2293@sdcsvax.UCSD.EDU> brian@sdcsvax.UUCP (Brian Kantor) writes: >>Especially good was connecting the top of the Big TC coil to the >>doorknob of the classroom door - so that anybody attempting to come in >>drew a big arc to his fingers. Worked especially well with the >>principal. >>Yes, I'm still alive. >But is the principal? :-) > -Ed I highly doubt that a high-frequency, low-current electrical current (100KHZ+) such as produced by a Tesla Coil would be likely to produce a fatal shock, because of "skin effect" (high-frequency currents would not pass near the heart). But it would sure be startling :-). -- ------------------------------- Disclaimer: The views contained herein are | dan levy | my own and are not at all those of my em- | an engihacker @ | ployer or the administrator of any computer | at&t computer systems division | upon which I may hack. | skokie, illinois | -------------------------------- Path: ..!{akgua,homxb,ihnp4,ltuxa,mvuxa, allegra,ulysses,vax135}!ttrdc!levy
commgrp@silver.bacs.indiana.edu (08/18/87)
Someone requested sources of Tesla Coil literature.
Lindsay Publications
PO Box 12
Bradley, IL 60915-0012
tel. (815) 463-3668
has a Technical Books Catalog which features a "lost technology"
series of reprinted rare books on Tesla Coils, electrical
machinery, storage batteries, metal work, heat engines,
alternative energy, physics experiments, and includes such arcane
topics as perpetual motion, embalming, how to make moonshine, and
even a calculus comic book. I've been well-pleased with their
fast service.
--
Frank Reid
reid@gold.bacs.indiana.edufrisk@askja.UUCP (Fridrik Skulason) (08/20/87)
There used to be a Tesla Coil Builders Accociation active. I have some of
their newsletters (from '82 and '83), which contain a number of construction
info. I don't know if they are still active - try contacting
Harry Goldmann
RD3 BOX 181
Glens Falls
N.Y. 12801
(Note - this address is a few years old and may be incorrect)
Also - another old address
Tesla Book Co.
c/o 1580 Magnolia Ave.
Milbrae, CA 94030
--
Fridrik Skulason Univ. of Iceland, Computing Center
UUCP ...mcvax!hafro!askja!frisk BIX frisk
"This line intentionally left blank"dmt@ptsfa.UUCP (Dave Turner) (08/22/87)
In article <275@askja.UUCP> frisk@askja.UUCP (Fridrik Skulason) writes: > Tesla Book Co. > c/o 1580 Magnolia Ave. > Milbrae, CA 94030 > The above address is incorrect. The Tesla Book Co. has moved to: Tesla Book Co. B.O. Box 1685 Ventura, CA 93001 (805) 643-0432 -- Dave Turner 415/542-1299 {ihnp4,lll-crg,qantel,pyramid}!ptsfa!dmt
ras2@engr.uark.edu (Richard A. Smith) (01/24/91)
I am in the process of building a Tesla coil and I would like to hear from all of you experimenters that have already done so. Advice, problems, experiences, resources, plans, etc. I am using a neon sign transformer of 15KV to start with and going form there. Right now I am building the Cap. that I will need to fire the spark Gap. My schematic looks like this: ---------------) (-----------| * + | Spark Ga | * * | | * * | Primar * * Secondary * 15kv ===== * * * ===== * * * | * * * - | * * * | * * ------------------------------ My Cap is sheet of plexiglass with Al foil on the outsides and cardboard to cover the foil. My peliminary ideal calculations show that I should get about .048 uF from it. My plans are to measure the cap at the Lab and also the inductance of the primary (6 turns of #12 wire 6" in diameter) and the sign transformer. calculate the resonant freq. and wind the secondary to match. Does anybody know the capacitance of #24 magnet wire wraped around a piece of sched 40 3 1/2" PVC per unit foot? I have eqns for the Inductance but not capacity. Does anybody see anything wrong with this design? Have a better Design? PLEASE tell me about it. Also the names of any books about the experiments of Nikola Tesla would be appeacated too. Thanks in advance Richard - -- Richard A. Smith | Dont look at me, I'm still an ras2@engr.uark.edu | undergrad!! University of Arkansas @ Fayetteville | Disclamer: I'm a college student.