A Back-To-The-Basics Tesla Coil

[jeff_behary]

Hello all,

I know there are many new people interested in Tesla and Tesla Coils each year, and so many times its confusing to find plans for something simple to build. Here is a simple Tesla Coil that gives a 12" discharge.



It isn't a perfect design, but a classic example of what a young person in the 1920s might be building. I've put a few modern materials (acrylic base) with a few vintage (bakelite, silk covered wire). This could easily be made with normal wire on a wooden base in bread-board fashion.

Basic Tesla Coil

There is also a brief movie.

The coil consists of:

9000V 60mA neon transformer
(3) .002 mfd 40kV Doorknob Capacitors, wired in parallel for .006 mfd.
a 4-series Tungsten Spark Gap
250 turns of wire on a 4.5" diameter PVC pipe (Secondary Coil)
5 turns of 1" copper ribbon for the primary coil
6" Copper Float (Topload)

Not the greatest coil ever made, but relatively simple and useful...



Jeff

[Karl_Palsness]

Study Tesla and other early experimenters

Study Tesla and other early experimenters!

That is what I keep telling people, you need to walk before you can run. As I have stopped most of my research and gone back to the basics and started working through what Tesla talked about in his writings. Reading works from that time period starting with Tesla, Kinraide, Karl Von Reichenbach, Farnsworth and John Bedini ect.

One of the most interesting insights I have had in recent times is to read early books such as Hawkins' Electrical dictionary 1930 (the meaning of the words will surprises you and the words they use we don't use will make since), Hawkins Electrical Guide from 1914, Audels new electric library 1929 and Cyclopedia of Applied Electricity 1920. Most of all reading Tesla books that he wrote is best of all...It helps to have a dictionary from that time period and the Tesla for Dummies book.

All the reading in the world will do you little good if you don't build as Jeff Behary also states. Again Jeff can teach all of us the art of making these machines. Things like the HairPin, Tesla coils, Radiant tubes ect can teach us a lot. You may not have seen the page on Jeff Behary's web page with the vacuum tubes used for electrotherapy. These are similar to a neon tube but they only have one electrode.

I can't say it enough, but start building these working machines and they will teach you a lot about what is going on.

Keep up the good work Jeff!

Karl

[morpher44]

Tesla's London Coil

I was very much influenced by the book
"Son of Tesla Coil" by George Trinkaus.
It discusses the benefits of a low-power coil.

Tesla's "London Coil" was immersed in oil,
had its secondary wired directly on its primary
(vastly better inductive coupling), no damping
of secondary oscillations, more efficient transfer
of energy with relatively low voltages ... and
can be adapted to solid state.

Tesla quote: "As sparks would soon destroy
insulation, it is necessary to prevent them".

Tesla went to these oil immersed coils in has later years.
The liquid oil has self-repairing properties.
To do the same in an open air coil, you would need to
spray on heavy layers of silicone.

There is a special advantage to oil's dielectric dynamics.

Tesla has patent #514,168 -- Oil Coil.
NIKOLA TESLA - Google Patent Search
He puts his capacitor in oil as well.

From this he obtains:
* lower current
* long duty cycle
* low maintenance
* quite operation
* emission-free operation
* compactness
* .... and hugely important ... SAFETY

I think if your goal is to create solutions that
drive florescent lights with low power, or
you want to experiment with less of an electric bill
and more safety, then perhaps Tesla London coil
is the way to go.
Yes its harder to build ... but probably worth it,
as Tesla went this route.

FYI

[jeff_behary]

Tesla's London Coil

Good ideas.

I did a crude repro of this type of coil, but with a semi-solid oil/wax composition.



It worked okay, but I should have followed Tesla's design exactly. It was there in the lecture for a reason! I did a flat spiral secondary instead of multi-layered.



The concept does work well, I think oil is really necessary though as you say. If I pushed the coil, arcs would come through the sides.

Here is a short movie.

http://www.electrotherapymuseum.com/...ionTest08B.wmv

It would be interesting to explore this further.
Maybe with a fish tank? Has anyone tried that?

Jeff

[jeff_behary]

Addendum to last post...

Here are the early photos of that coil and testing for those interested. The insulation was toilet wax ring seals (new, of course!)...horrific to work with!

Reproduction 1892 Tesla High Frequency Induction Coil from London Lecture

[Later correction: I though I used toilet rings, one step worse, I tried to make my own. Linseed oil, mineral oil, and beeswax. It was vaseline like and "goo-y" in character.]

[jeff_behary]

Dictionaries

Study Tesla and other early experimenters!

That is what I keep telling people, you need to walk before you can run. As I have stopped most of my research and gone back to the basics and started working through what Tesla talked about in his writings. Reading works from that time period starting with Tesla, Kinraide, Karl Von Reichenbach, Farsworth John Bedini ect.

One of the most interesting insights I have had in recent times is to read early books such as Hawkins' Electrical dictionary 1930 (the meaning of the words will surprises you and the words they use we don't use will make scene), Hawkins Electrical Guide from 1914, Audels new electric library 1929 and Cyolopedia of Applied Electricity 1920. Most of all reading Tesla books that he wrote is best of all...It helps to have a dictionary from that time period and the Tesla for Dummies book.

All the reading in the world will do you little good if you don't build as Jeff Behary also states. Again Jeff can teach all of us the art of making these machines. Things like the HairPin, Tesla coils, Radiant tubes ect can teach us a lot. You may not have seen the page on Jeff Behary's web page with the vacuum tubes used for electrotherapy. These are similar to a neon tube but they only have one electrode.

I can't say it enough, but starting building these working machines and they will teach you a lot about what is going on.

Keep up the good work Jeff!

Karl

Thanks for the kind words, Karl. Don't trust my words though, experimentation is the best bet. Every day brings something new. I make mistakes all of the time. They are good teachers, mistakes!
I'm slowing down a lot though these days...

You mention a good point about period books. There is another dictionary that is really spectacular - 1890s vintage - "Standard Electrical Dictionary" by Sloane. Its AMAZING how this dictionary has things in it that don't appear in any other dictionary ever published. The electrical world was changing so fast not even the dictionary could keep up!

Also, to keep up with the lingo is a good point. I remember from Tesla's lecture reading that placing a small lamp in the base of the spark gap box would improve things. So I did. Literally. At around 18 years old I put a small light bulb in the base of a spark gap and noticed absolutely nothing. Years later (well, 15 to be exact) I re-read that part of the lecture and I realised how ignorant I was - LAMP. What's a LAMP? How about a SPIRIT LAMP? Of course. So I tried an alcohol lamp. BAM! Burning Alcohol gives off hydrocarbons. This lowers the striking voltage of the gap and removes oxygen from the environment. Something people copied left and right two decades later. Spirit lamp! No wonder the spark gap has holes in the base?! Not so the light bulb could "breate"?!

It would be interesting since you're in Canada to study the differences in Canadian electrical dictionaries and US from that time period. Well, for that matter I'm sure all countries electrical dictionaries in the beginning were all completely different treasure chests. In the Sloane Tesla hardly gets mention, but they show a nice diagram of the air compressor Elihu Thomson used for his spark gap on his high frequency coil. They also have some great pictures of batteries and arc lights of all varieties. Cool stuff!!

Jeff

[morpher44]

London coil

Good ideas.
I did a crude repro of this type of coil

That is very cool.!!!

[boguslaw]

jeff and karl

I think you should read this article : Article:Tesla DC Thermoelectric Coils - PESWiki

I think you are the right and maybe only persons who can recreate Tesla DC coils and radiant energy and see it experimentally.

I believe that without radiant energy there is no wireless energy transfer and with radiant energy there is COMPLETE new science a a lot of miracles possible...

[jeff_behary]

Circuit Controllers / The original basis of Tesla coils

Ohhh.....



These early Tesla oscillators and Circuit Controllers really hold the keys of all high frequency work. These were Tesla's own origins, and these apparatus set forth the basis for the rest. The secrets ARE with that apparatus. I've argued (mainly to the wall) for years that we can't improve on anything until with start here.

If I had the funding, the following coils would be more than Solidworks drawings...

Tesla Patent 609,251


Tesla Patent 609,247


Tesla Patent 609,248


Tesla Patent 583, 953




I think I did these only to torture myself. Well, they ended up in the lecture on Long Island for the 150th Anniversary of his birth. I hope they publish these on video one day, they were really good lectures by everyone. A lot of sincerety.

Jeff

[Slovenia]

Very Good Work!!

Wow Jeff, very well done!!

Thanks so much for sharing this with us.

[cody]

Jeff,

Im trying to collect info on construction guidelines of a magnifying transmitter for a project im working on. By chance have you read the new lab notes that were released from the time period after colorado springs which were from new york? Im assuming these would have more precise info than the patent has in it. Have you or anyone else read it and would like to share what info it contains on the subject. Or any other info you have on the subject would be great. One of my main stumbling blocks is the design of the secondary. There is a lot of conjecture over weather or not to construct it more along the lines of current radio theory being wide with spaced turns, or to stick with the tightly wound long narrow secondarys we are all use to seeing. To me the patent makes it seem like he constructed it much like todays tesla coils, but his colorado notes describe a very different secondary. The patent isnt very precise and could be somewhat misleading. What do you think?

[Raui]

Im trying to collect info on construction guidelines of a magnifying transmitter for a project im working on. By chance have you read the new lab notes that were released from the time period after colorado springs which were from new york? Im assuming these would have more precise info than the patent has in it. Have you or anyone else read it and would like to share what info it contains on the subject. Or any other info you have on the subject would be great. One of my main stumbling blocks is the design of the secondary. There is a lot of conjecture over weather or not to construct it more along the lines of current radio theory being wide with spaced turns, or to stick with the tightly wound long narrow secondarys we are all use to seeing. To me the patent makes it seem like he constructed it much like todays tesla coils, but his colorado notes describe a very different secondary. The patent isnt very precise and could be somewhat misleading. What do you think?

Here are two books that might be able to help you out a great deal.

Condensed Intro to Tesla Coils - Eric Dollard
Theory of Wireless Power - Eric Dollard

Unfortunately I haven't been able to find an online copy of the New York notes and I don't have the sort of money lying around as to just purchase them willy nilly.
Also, just a note; Not sure if it is in Condensed Intro to Tesla Coils however Eric Dollard, who is the only person to truly replicate a magnifying transmitter, has said in the talk he gave to SBARC in 1996 to use heavy sheet copper windings that are a 1/3 wide as they are long when dealing with RF conductors. If you have a look at his telsa coils you'll see this put into practice. Hope this help

Raui

[cody]

Raui,

Thanks for the links, but i have already read both of those. Actually they have been the best info ive found on the subject so far. Im well aware of that video as well, great info in there. I know dollard is very smart, i just really want to hear what tesla has to say about the subject. Im in the same situation you are, i dont feel like spending the money for the new lab notes and cant find a free copy anywhere on line. Its mainly just the "extra coil" as tesla called it that im really curious about because his colorado notes seem to differ from the description in the patent. Did he discover something new in that year after colorado which went into the patent details? Guess ill have to save up for that book to find out

[uusedman]

Those arcs coming out of the tesla coil on top, can they kill you? are they dangerous?

I don't know if i have the guts to get close.

thanks

abe

[seth]

Those arcs coming out of the tesla coil on top, can they kill you? are they dangerous?

I don't know if i have the guts to get close.

thanks

abe

No they cant - they are at such high frequency that the current passes over the surface of the skin and into the ground. At lower frequencies they certainly could kill, and the massive ones that tesla was making i imagine could probably kill. Might be wrong here though...im no expert.

Heres a video of the skin effect:

YouTube - skin effect

Nothing to be afraid of

and damn good fun too!

If you want wireless effects like tesla coils produce but without all those amps, volts, arcs, and loud sparking noises build a slayer exciter - they do the same but run on 1AA batteries.....safe as houses and fairly easy to build....much easier than a tesla coil.