This also a must read (Sorry, stprue)
http://en.wikipedia.org/wiki/Lecher_lines
Tesla did not come up with anything new here or extraordinary.
Poor Karl Palsness does it no justice either. What is extremely amazing is the audience of Karl's showing such amazement during his demonstration of common radio frequency and resonance basics.
And yes, everything demonstrated is a common effect explained in the most basic physics texts.
Sorry to sound like a prude. I am rarely on the side of classic physics but there is absolutely no magic in the hairpin circuit except that it is a fantastic way to learn about radio and resonance.
No problem WaveWatcher. I did not make any claims and have posted the vids so people could learn!
I completely agree with you!
;D
The following was merged from a previous post from stprue
Here is some mandatory viewing
For Some!
lol
~Here is a simple Don/Hairpin type device! Now show me yours!~
Didn't the hairpin circuit become the primary of the Tesla Coil?
I don't know if it became the primary or not.
stprue,
There are many things I don't know and one of them is what your application of a Lecher line will produce. Don't let my comments have a negative effect on your experiments.
What a Lecher line is basically an open ended balanced transmission line (Tesla actually used a closed ended hairpin shape).
Once this device is well understood there may be more things to expect from your application.
another hairpin experiment: http://www.df.lth.se/~snorkelf/Longitudinal/node2.html
Francis Nipher did a similar experiment with a piece of wire that move along like a micron-worm (as opposed to an inch-worm) when pulsed by capacitor discharges.
Agreed w/ you guys..
While the effects of standing waves are interesting, what I'm really interested in though is the transformer he has built to tesla's specifications. About halfway through the video in stprue's 7th reply he talks about how tesla documented step by step how to construct such a coil.
I would like to read this document of tesla's and consider constructing one of these HV transformers... that is if it offers something that a regular transformer doesnt...
Comments, criticisms?
Can anyone think of how we might also get a copy of this book he mentions?
Thank you WW for bringing that to light. Now as you say, it's a matter of determining if it evolved into something else for these purposes.
.99
Quote from: WaveWatcher on 2010.01.05, 12:04:49
This also a must read (Sorry, stprue)
http://en.wikipedia.org/wiki/Lecher_lines
Tesla did not come up with anything new here or extraordinary.
Poor Karl Palsness does it no justice either. What is extremely amazing is the audience of Karl's showing such amazement during his demonstration of common radio frequency and resonance basics.
And yes, everything demonstrated is a common effect explained in the most basic physics texts.
Sorry to sound like a prude. I am rarely on the side of classic physics but there is absolutely no magic in the hairpin circuit except that it is a fantastic way to learn about radio and resonance.
from the link above:
QuoteShort lengths of Lecher line are often used as high Q resonant circuits, termed resonant stubs. For example, a quarter wavelength (λ/4) shorted Lecher line acts like a parallel resonant circuit, appearing as a high impedance at its resonant frequency and low impedance at other frequencies. They are used because at UHF frequencies the value of inductors and capacitors needed for 'lumped component' tuned circuits becomes extremely low, making them difficult to fabricate and sensitive to parasitic capacitance and inductance. One difference between them is that transmission line stubs like Lecher lines also resonate at odd-number multiples of their fundamental resonant frequency, while lumped LC circuits just have one resonant frequency.
A cat's tail of visible energy !
P.S Please post on my bench ;D
Quote from: Grumpy on 2010.01.05, 18:18:59
Short lengths of Lecher line are often used as high Q resonant circuits, termed resonant stubs. For example, a quarter wavelength (λ/4) shorted Lecher line acts like a parallel resonant circuit, appearing as a high impedance at its resonant frequency and low impedance at other frequencies. They are used because at UHF frequencies the value of inductors and capacitors needed for 'lumped component' tuned circuits becomes extremely low, making them difficult to fabricate and sensitive to parasitic capacitance and inductance. One difference between them is that transmission line stubs like Lecher lines also resonate at odd-number multiples of their fundamental resonant frequency, while lumped LC circuits just have one resonant frequency.
Yea ;D
And when you bend it into an open loop all kinds of weird things can happen.
Quote from: WaveWatcher on 2010.01.05, 22:47:14
Quote from: Grumpy on 2010.01.05, 18:18:59
Short lengths of Lecher line are often used as high Q resonant circuits, termed resonant stubs. For example, a quarter wavelength (λ/4) shorted Lecher line acts like a parallel resonant circuit, appearing as a high impedance at its resonant frequency and low impedance at other frequencies. They are used because at UHF frequencies the value of inductors and capacitors needed for 'lumped component' tuned circuits becomes extremely low, making them difficult to fabricate and sensitive to parasitic capacitance and inductance. One difference between them is that transmission line stubs like Lecher lines also resonate at odd-number multiples of their fundamental resonant frequency, while lumped LC circuits just have one resonant frequency.
Yea ;D
And when you bend it into an open loop all kinds of weird things can happen.
such as?
@stprue
I looked for a wihle but was not able to reply to your thread is it locked?
Quote from: Grumpy on 2010.01.05, 13:17:25
another hairpin experiment: http://www.df.lth.se/~snorkelf/Longitudinal/node2.html
Francis Nipher did a similar experiment with a piece of wire that move along like a micron-worm (as opposed to an inch-worm) when pulsed by capacitor discharges.
Ah! The true and original hairpin test by Ampere. That article also shows the worst step in electromagnetics taken by the folks that butchered Maxwell by incorporating Grassmann's postulations instead the empirical results and theories by Ampere. I have the impression this was done just so vector math would fit.
BTW: The Ampere hairpin has little to do with the so-called 'Tesla hairpin'. Good that this is brought to light anyway.
Thanks for moving this thread from my bench!
Quote from: WaveWatcher on 2010.01.06, 11:55:43
Quote from: Grumpy on 2010.01.05, 13:17:25
another hairpin experiment: http://www.df.lth.se/~snorkelf/Longitudinal/node2.html
Francis Nipher did a similar experiment with a piece of wire that move along like a micron-worm (as opposed to an inch-worm) when pulsed by capacitor discharges.
Ah! The true and original hairpin test by Ampere. That article also shows the worst step in electromagnetics taken by the folks that butchered Maxwell by incorporating Grassmann's postulations instead the empirical results and theories by Ampere. I have the impression this was done just so vector math would fit.
BTW: The Ampere hairpin has little to do with the so-called 'Tesla hairpin'. Good that this is brought to light anyway.
Thanks for moving this thread from my bench!
Flip the page to: http://www.df.lth.se/%7Esnorkelf/Longitudinal/node3.html
This is where Tesla started.
When pulsed, there is a force inside the curve of the Lecher Lines. This is where Tesla placed his secondary coil and first saw the arcs that were much greater in length than he expected with the voltage applied.
An example is here: http://www.electrotherapymuseum.com/2009/Hairpin/index.htm
See the arcing pancake coil? 3" spark with 3500v is pretty good. 10kv DC will not spark this far.
See that the when he lights a bulb, the pancake stops arcing? He is shorting the hairpin above the pancake coil, so why doesn't the pancake continue to arc?
If we can induct electrostatically and magnetically, why not tempicly?
Hi all,
Is this what is being talked about in this thread ???
Published in 1893
"The Inventions, Researches and Writings of Nikola Tesla"
By Thomas Commerford Martin and Nikola Tesla
The Inventions, Researches and Writings of Nikola Tesla - Page 339 ( Google Books ) (http://books.google.com/books?id=bhrreukJiLgC&pg=PA339&lpg=PA339&dq=tesla+figs.+183a&source=bl&ots=OBM2DqFLNu&sig=OTkzD9KfwwIxK9AwEeNed5sOMhM&hl=en&ei=C3JISsyiI52xtgfy2MWMCg&sa=X&oi=book_result&ct=result&resnum=1)
Fuzzy
;D
that is where it started - several other things have been brought to light that no one wants to talk about
question:
if there are nodes and antinodes along the lines, as everyone knows there are, are they transverse or longitudinal?
Who can answer with actual measurements?
They would be both. Hard to get a good measurement from a feather hanging on a thread.
Quote from: WaveWatcher on 2010.01.07, 18:06:08
They would be both. Hard to get a good measurement from a feather hanging on a thread.
ah-ha!
Fuzzy
Here's the index to that book, i will scan it when it arrives ;) 5-10 days for UK though :(
Peter
44 meg
http://www.archive.org/details/inventionsresear00martiala
I have a pdf that is 15 megs - any way to upload it?
Thanks for the link Grumpy
I havea copy now ;)
Cheers
Peter
Careful what you drive it with ;D
Quote from: Grumpy on 2010.01.07, 04:12:50
that is where it started - several other things have been brought to light that no one wants to talk about
question:
if there are nodes and antinodes along the lines, as everyone knows there are, are they transverse or longitudinal?
Who can answer with actual measurements?
AC or DC pulse??
I have driven mine with AC through a spark gap - works ok
DC pulse - much better
Thinking of trying the BulbO'Death driver... Where is my lead suit??
@wavewatcher
QuoteTesla did not come up with anything new here or extraordinary.
Poor Karl Palsness does it no justice either. What is extremely amazing is the audience of Karl's showing such amazement during his demonstration of common radio frequency and resonance basics.
And yes, everything demonstrated is a common effect explained in the most basic physics texts.
Sorry to sound like a prude. I am rarely on the side of classic physics but there is absolutely no magic in the hairpin circuit except that it is a fantastic way to learn about radio and resonance.
I am not sure I would agree, many times what we see is based on what we know in which case the very act of observation is biased from the start. The origin of Tesla's hairpin circuit can be seen here---http://www.tfcbooks.com/tesla/1898-11-17.htm, the first set of diagrams Fig 3, Notice where Tesla has placed the conductors C and C'.
Nikola Tesla Quotes:
QuoteOne of the prominent characteristics of high frequency or, to be more general, of rapidly varying currents, is that they pass with difficulty through stout conductors of high self-induction. So great is the obstruction which self-induction offers to their passage that it was found practicable, as shown in the early experiments to which reference has been made, to maintain differences of potential of many thousands of volts between two points-not more than a few inches apart-of a thick copper bar of inappreciable resistance.
Here Tesla refers to the phenomena whereby due to the nature of the currents utilized even a short thick copper bar will offer a great deal of resistance to the current even though this thick copper bar has basically no ohmic resistance. Does this sound like "common radio frequency" as you stated prior? What mechanism can offer a great deal of resistance even though it has "no" ohmic resistance? When you find the answer to this last question you will also understand why both Ohm's Law and Kirchhoff's Laws have little if no application in most of Tesla's circuits as well as why you cannot use distributed inductance nor distributed capacitance calculations.
QuoteAs before stated, when the oscillations in the primary and secondary circuits are in synchronism, the points of highest potential are on some portion of the terminal T. The synchronism being perfect and the length of the secondary coil just equal to one-quarter of the wave length, these points will be exactly on the free end of terminal T, that is, the one situated farthest from the end of the wire attached to the terminal. If this be so and if now the period of the oscillations in the primary be shortened, the points of highest potential will recede towards the secondary coil, since the wave-length is reduced and since the attachment of one end of the secondary coil to the ground determines the position of the nodal points, that is, the points of least potential. Thus, by varying the period of vibration of the primary circuit in any manner, the points of highest potential may be shifted accordingly along the terminal T, which has been shown, designedly, long to illustrate this feature.
Here we should understand that Tesla has always made a clear distinction between wave period and frequency as they are two completely different things, frequency is a measure of distance between two points in a wave and wave period is the time taken for the identical points in a wave to pass a static point--wave period is relative to wave speed frequency is not. It should also be understood Tesla makes a clear distinction between "vibration" and "oscillation" as they are two completely different things, Keely states the difference in these qualities very well---
"Oscillation is a rhythmically recurring translatory movement."
"Vibration is the rhythmical motion of a body within itself."
You see it is very easy to apply our own bias or difference in perception to the things we see and read but we should understand that Tesla has made this distinction of terms for a very good reason, consider why it took the boy's at MIT almost 100 years to figure out how Tesla could transmit wireless power? I also believe most everything can be explained with conventional physics however the real issue is that physics has still not figured out what in the hell Tesla was actually doing, it is one thing to understand physics but it is quite another to have the knowledge and skill to apply it in a creative manner such as Tesla did 100 years ago. We could generalize this thought even further, everyone has an opinion of many things but how many can apply it? It was only a few years ago that I first built Tesla patent #568177 to Tesla's specifications and what I found may surprise you, the first effect noticed was that my oscilloscope four feet away with no leads attached to anything started emitting a loud internal cracking noise, next all metallic objects within four or more feet would arc to all other metallic objects sometimes up to 1/2" arc's. This is not "common radio frequency" it is something else, as Tesla states countless times the effect is determined not by frequency but the rate of change, the make and break of the circuit. I have found that if you want to understand Tesla you have to take at least a few steps in his shoes, you have to see things from his perspective, you have to listen to him from his perspective. I will post a scopeshot from a real Tesla circuit later tonight when I get home, you will notice there are two disctinct waveforms in this scopeshot, one is low potential around 50v the other a higher potential near 350v. This scopeshot is from connections made across a single 1uF capacitor from a single channel oscilloscope, in the mean time I want you to consider how a single channel oscilloscope with two standard leads has detected "two" distinct currents in a single conductor? As well consider how one of these currents can power a load while the other moves unimpeded through the circuit? There is a very good reason why Tesla speaks of "current(s)" in a plural form in his patents.
Regards
AC
To save some typing here is my response to another forum (with edits to apply to here) :
If the two rods are not one piece and bent into a hairpin shape the device is a replication of Lecher lines.
http://en.wikipedia.org/wiki/Lecher_lines
--------
I watched Karl's video again and still see no signs of anything that isn't produced by transverse waves.
The video link provided by xxxx (yet another Lecher line experiment decalared a hairpin circuit) even makes statements something like 'and this cannot happen with EM'. Sorry to say but in almost every case exactly the opposite is true. It is confirmation that transverse waves are at play. The only exception is near the end with the column of water being drawn with the wire. This related more to things not discussed in the video.
One of the big problems here is folks can't see the difference between RE and RF(radio frequency energy).
An example of radiant energy is the light or heat radiating from a light bulb (longitudinal or LEM). Radio frequency energy can be LEM or TEM or both and always is (Transverse electro-magnetic like the ripples on a pond).
If the waves being sent up the Lecher lines were LEM the light being used for a shorting bar would not be brightest while the shorting bar is horizontal.
Folks get me wrong. I know LEM is possible and has the properties declared. I know Tesla was probably the greatest experimenter and inventor that ever lived. I also know Lecher invented this method and Tesla's hairpin circuit was a hairpin shape and included other things not shown by either of these videos.
Make no mistake. Both of these videos demonstrate the beginning of spark gap radio transmitter technology, hard and talented work but not much more.
---------
Addition:
People need to understand that Tesla had a broader understanding of induction. In the classic Faraday description the root is the relationship between the magnetic field and the conductor. In Tesla's understanding it also includes not considering the magnetic field - or using perpendicular induction. This is demonstrated in the coils by AgentGates of OU. This is where 'stout' rods come into play and Tesla describing a short conductor with high self induction with low frequencies. Using book induction this is impossible. Using Tesla's induction it is a fact.
Peeps call a Lecher line a hairpin circuit. This is wrong. Grumpy has provided links and pics of true hairpin circuits. If you look at those you will see there is more to the experiment than a demonstration of a basic spark gap radio transmitter.
As for how a short wire can provide high impedance..... Again - basic, standard transverse radio propagation principles.
You can connect a lamp across a short rod which measures zero ohms and light it easily. All it takes is pumping that rod with a frequency equal to 4 times the wavelength of the rod.
Like I said in chat:
Every one of my HAM antennas measure zero ohms at the feed point - with a DC ohm meter. However, some have impedances of 50, 75, 300 and 600 ohms at the operating frequency.
Again, nothing demonstrated in the referenced videos demonstrates anything than isn't correctly explained by a basic understanding of wave propagation and resonance.
This includes mention of tickling skin and purple or blue light under the skin. Folks should avoid that.
Tesla hairpin copper bar didn't get interesting until he placed a coil inside the curve.
Doesn't the high impedence of the copper bar indicate that the energy of the pulse will be forced into the space around the bar and not in the bar itself? The dieldctric on the bar, if there is any, is very thin and hardley able to contain all of this energy. The excess goes to polarizing the so-called vacuum. Same goes for vacuum caps. What is storing the charge? Sure as hell is not the plates or wires.
I do not trust your comments wavewatcher and I do understand spark gap transmitters! I think there is something else going on here. I wish I had $$ for HV parts so I could test more :P
I can say this for sure... feeding a tesla hairpin with caps a gap and a nst is different than feeding it with a quenched disruptor at the correct frequency
Quote from: stprue on 2010.01.18, 18:50:17
I do not trust your comments wavewatcher and I do understand spark gap transmitters! I think there is something else going on here. I wish I had $$ for HV parts so I could test more :P
Since I've used Lecher lines in many different configurations for quite a few different reasons and I have never built a Tesla hairpin...
I think there might be more to Tesla's hairpin circuit. I have serious doubts there is anything more to Lecher lines.
I just wish folks would stop calling simple Lecher lines Tesla's hairpin.
You don't need to trust anything I say. The only thing I trust are results on the bench.
:P ;D
http://www.transformacomm.com/en/tech/tesla-hairpin-circuit.htm (http://www.transformacomm.com/en/tech/tesla-hairpin-circuit.htm)
1. The hairpin needs to have it resonant frequency measured with caps in place
2. It needs to be driven at a function of its resonant frequency
3. It needs to be driven with unidirectional DC pulse - so every pulse is additive
4. it needs to be constructed of thin wall tubing
5. spark gap needs to be inline with the circuit rather than strung off somewhere on leads
This should create a very pronounced node / antinode at a number of locations
Just my opinion...
I know this ! I have a question will it interfere with my computer near buy? I dont want to build something that will screw up my equipment!!!
depends how much power you put into it and if your power supply shares a ground path with your equipment..
run your power supply off a dedicated breaker if possible
always use an AC line filter between your supply and the wall socket ... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200429072124 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200429072124)
big resistors are good too like the " terry filter " - http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360228405308 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360228405308)
(http://www.hvtesla.com/images/tesla%20coil%20terry_filter.jpg)
Very good info and thank you!
;D
stprue - watch these 1- 9 videos
You need to be aware that anything on the supply side of the capacitors will kill you
Anything on the hairpin side of the capacitors has the potential to kill you if a cap fails and conducts as a short
So when you touch the hairpin use the back of your hand NEVER GRAB IT WITH YOUR HAND if it fails you wont be able to let go.
NEVER touch both sides with both hands at the same time.. if it fails it will kill you
Remember if you put the light bulb in the water with your hand dont keep it there for long.. if for any reason a cap failed it will probably kill you
This is kind of an advanced build if you are not use to working with HV