Tesla's mysterious Phantom Streams

[grizli]

Posebni pozdrav lighty, i pivo,

I presume you understand that I am not lighty, actually I dont know him at all, but I am also from Croatia like he is.

Yes its all logical about freq what you wrote, but lets compare for example 50 meter wire length pancke coil and 200 m wire length coil .

First we put both coil at freq much lower than 1/4 wavelength , for example 50 khz, I presume they will both produce strong loud sparks.

Now we set freq that equals 1/4 wavelength= wire length for long wire coil (presume 250 khz without calcuation) , and that we put on the same freq low turn 50m coil.
Will than long wire coil give phantoms and flamish sparks more likely than low turn coil ?

So is it true that low turn wire coil gives flamish sparks at higher freq than long wire coil , or it does not matter ?

And just to say I compared low C big primary L with high C and low primary L at 500khz (for my 100 m coil) and got the same phantomish result , but higher C would mean more power(but havent used change of ballast to HV transformer to match capacitor unfortunately, higher C requires higher powered HV transformer, adjustable ballast..)

I read much Tesla stuff but at one paper which I can not currently find he says that if you use 1/4 wavelength for wire length you do not waste energy for hot loud streamers at all ...(if you tend to build any kind of wireless , ou and similar device).

Problem is that I currently dont have much different pancake coils like you to compare this claim.

And another question related to making pancakes:
we have single layered and multilayered...

Will there be any difference in behavior if coil will be build this way: Outer (opposite to center) turns witch much turns per layer and inner near center with just one turn per layer,
what about opposite, inner with much turns per layer and outer with just one turn.

[boguslaw]

Phantom streamers ? : Eugen Goldstein

[jeff_behary]

Coils...

I presume you understand that I am not lighty, actually I dont know him at all, but I am also from Croatia like he is.

Yes its all logical about freq what you wrote, but lets compare for example 50 meter wire length pancke coil and 200 m wire length coil .

First we put both coil at freq much lower than 1/4 wavelength , for example 50 khz, I presume they will both produce strong loud sparks.

Now we set freq that equals 1/4 wavelength= wire length for long wire coil (presume 250 khz without calcuation) , and that we put on the same freq low turn 50m coil.
Will than long wire coil give phantoms and flamish sparks more likely than low turn coil ?

So is it true that low turn wire coil gives flamish sparks at higher freq than long wire coil , or it does not matter ?

And just to say I compared low C big primary L with high C and low primary L at 500khz (for my 100 m coil) and got the same phantomish result , but higher C would mean more power(but havent used change of ballast to HV transformer to match capacitor unfortunately, higher C requires higher powered HV transformer, adjustable ballast..)

I read much Tesla stuff but at one paper which I can not currently find he says that if you use 1/4 wavelength for wire length you do not waste energy for hot loud streamers at all ...(if you tend to build any kind of wireless , ou and similar device).

Problem is that I currently dont have much different pancake coils like you to compare this claim.

And another question related to making pancakes:
we have single layered and multilayered...

Will there be any difference in behavior if coil will be build this way: Outer (opposite to center) turns witch much turns per layer and inner near center with just one turn per layer,
what about opposite, inner with much turns per layer and outer with just one turn.

Ah, I was reinforcing the greeting to Lighty with addition of some Beer!

I will try and answer the questions simple, to my knowledge, but for sure experimentation reveals everything...

It seems for me "generally" you can get hotter sparks from coils of less wire, and longer sparks from coils of more wire. To some extent though, these effects can be "forced".

To contradict this somewhat, I think at 1/4 wavelength, accurate resonance will always give long hot sparks for most efficiency no matter what. In this situation, a small change in input power will reveal great things on the nature of the spark.

For me it is easier to get resonance with more wire, because larger condensers allow more room for mistakes or miscalculations . I am sure though someone can make very accurate higher frequency coils if their condensers can be adjusted in really small increments. Tesla did this with the adjustable caps under oil - good idea!

I have seen coils with really a lot of wire (as many as 4000 turns), give sparks of all varieties - from cold and snapping to hot fire - simply by adjusting the input power from 100 watts to 1000 watts. In seeing this coil, which must be in ideal resonance, if the apparatus was not visible I might think it was a different power supply for each situation. There are times when some coils work so much better than others, many times with little logic, or rather hidden or forgotten logic.

There are so many variables rules get difficult. For example, how much current and voltage you have for a transformer will effect how efficiently the cap charges and discharges.

Sorry if I am not helpful with this post. I confuse myself also.

For multilayered pancakes, I have tried layers of the same number of turns, and as you mention more in the middle and more outside.

It seemed to me logically in the beginning that the most turns outside were best because the voltage is lower and the insulation strain must be less...and with fewer turns per layer in the middle where the voltage is highest. But in practice, the longer turns on the outside tend to short-circuit! I was surprised by this, but it seems to always happen that way - in any Pancake configuration, the turns of most resistance tend to be where problems occur. But with more turns per layer on the outside, it seems better for close coupling with the primary.

The opposite with more turns in the middle and less on the outside works well, but I found either more power or higher voltages are normally required because the coupling is looser between P & S coils.

That's my ideas. Every new coil I learn something new, or make a new mistake, and when I think I really understand something the next coil always proves it wrong.

Jeff

[jeff_behary]

Kanalstrahlen

Phantom streamers ? : Eugen Goldstein

Those are cool. I need to do a better study of that tube since you mention that! Good idea.
Turn Of The Century Electrotherapy Museum - Canal Rays / Canal Ray Tube - Channel Rays / Kanal Strahlen

Turn Of The Century Electrotherapy Museum - Canal Rays / Canal Ray Tube - Channel Rays / Kanal Strahlen

Jeff

[morpher44]

Gutta-Percha Insulation

In reading "Experiments with Alternate Currents of High Potential and High Frequency" and the section where he discussions phantom streams,
I see he mentions that he preferred to use wires with
gutta-percha insulation.

"Gutta-percha will withstand much more than an equal thickness
of oil, and this advantage should be secured at any price."

Gutta-percha - Wikipedia, the free encyclopedia

[grizli]

To contradict this somewhat, I think at 1/4 wavelength, accurate resonance will always give long hot sparks for most efficiency no matter what. In this situation, a small change in input power will reveal great things on the nature of the spark.

For me it is easier to get resonance with more wire, because larger condensers allow more room for mistakes or miscalculations . I am sure though someone can make very accurate higher frequency coils if their condensers can be adjusted in really small increments. Tesla did this with the adjustable caps under oil - good idea!

More ore less I agree, but Tesla himself never considered tesla coil as we can see all over the internet: Classic tesla coil, which secondary has to resonate with primary and has also its own resonance freq,
But for me pancake seems to be much different than tubular classic tesla coil with closed wound wire windings : Cause wire not close together, I mean neighbor wire turns...

Also he spoke something about distributive capacity , classic TC has relative high distr. cap. compared to pancake coil


how to measure actual LC resonance without scope... I tr to use mw (or lw) radio reciever , but i doubt it will be accurate..

But I ll soon try my pancake at 1/4 wavelenth , and more power...

It will be very nice to make oil adjustable cap for about 2nF , usually my multi sandwitch cap has 2nF increments...

To contradict this somewhat, I think at 1/4 wavelength, accurate resonance will always give long hot sparks for most efficiency no matter what. In this situation, a small change in input power will reveal great things on the nature of the spark.

Its interesting that TESLA in at least TWO patents mentions EXACTLY 1/4 wavelength for wirelength, but never mentions any kind of classic primary to secondary resonance , like classic TC(web populated)

1/4 wavelength for wire length makes TC somehow FIXED unit(related to primary LC circuit and power supply).... longer wire lower LC freq , lower input voltage for the same power.






p.s sorry for random answers..

[Sputins]

Reasonat Freq without a scope...?

Grizli,

One way to measure to resonance without a scope:

You need a Audio generator however..

Take two high brightness LED's, solder them back to back. I.e. anode to the cathode of the other, and vice-versa.

Then connect one pair of the soldered LED legs to the Positive output of your Audio Generator and the other pair of soldered LED legs to a short wire with a alligator clip on it..

Attach the alligator clip to the Tesla coil to be measured.. Turn the output of the audio gen fully up and turn the dial to hunt for the resonant frequency(s). The LED'S should light up when you hit the resonant point(s).

Then just read your audio gen frequency on the dial or connect a DMM to measure frequency..

Seems to work really well for me..

[grizli]

Grizli,

One way to measure to resonance without a scope:

You need a Audio generator however..

Take two high brightness LED's, solder them back to back. I.e. anode to the cathode of the other, and vice-versa.

Then connect one pair of the soldered LED legs to the Positive output of your Audio Generator and the other pair of soldered LED legs to a short wire with a alligator clip on it..

Attach the alligator clip to the Tesla coil to be measured.. Turn the output of the audio gen fully up and turn the dial to hunt for the resonant frequency(s). The LED'S should light up when you hit the resonant point(s).

Then just read your audio gen frequency on the dial or connect a DMM to measure frequency..

Seems to work really well for me..

Hmm ,I dont quire understand what kind of audio generator do you refer, what device you actually mean, but logical if its "audio" than max freq should be 20 khz

alligator clip ? dont know the meaning of this

all in all I dont have audio generator..

so far I measure using bipolar transistor oscillator circuit which has original TC L and C attached and freq counter multimeter.


p.s Jeff your coils look so nice.. what kind of mold you have to put wax coil outide it so nicely.. presume silicone one, but I just cant anywhere buy right one..

[jeff_behary]

Moulds for coils

I am indeed using Silicone moulds, but you are correct - finding them is difficult. A few years back every kitchen store here in USA was selling them for cakes. But eventually everyone learned they are horrible for making cakes. Yes, they demould easily, but pour in cake batter and try to move it. You will have cake on the floor instantly, down the cabinet - or worse, very worse, in the bottom of the hot oven. Literally they vanished from the market, with exception of some very expensive stores.

I have made more than 100 Pancake Coils in wooden boxes before I found something that made nice moulds. You must constantly search in your area. There are some baking pans with removeable bottoms, "Spring Form Pans" in english. They work well enough, and can be found in Europe too but I don't know the name.

The problem even with Silicone - they are not deep enough. A flat spiral of around 250mm diameter should have at least 75mm of insulation (wire in centre) if not 100mm for best results.

Need to find a country that makes very thick cakes. Where are people the most fat? Ah, USA. But they're aren't here either!

[jeff_behary]

Gutta Percha

In reading "Experiments with Alternate Currents of High Potential and High Frequency" and the section where he discussions phantom streams,
I see he mentions that he preferred to use wires with
gutta-percha insulation.

"Gutta-percha will withstand much more than an equal thickness
of oil, and this advantage should be secured at any price."

Gutta-percha - Wikipedia, the free encyclopedia

Some materials I have had little luck to find. Gutta Percha is one. Ebonite or Vulcanite is another. This later material exists from time to time but very expensive - 18mm x 600 mm around $50US. Ouch. Any luck in Croatia or Europe elsewhere?

[Sputins]

Any price?

Hehe, Tesla says Gutta-percha it should be secured at ANY price Mr Behary!!

What about making your own special silicone moulds or having then made for you? Then you could have the perfect size, any decorative patern, even a "Behary" logo built in? What about fibre-glass moulds, or does the wax mixture stick too much?

Could you elaborate on your current (optimum) mould mixtures. I.e. percentage of wax/rosin, or just wax? Colouring? (Coloring US spelling)

I have access to large amounts of Mirco-fine wax powder. Would that be good to use? (try it and see I guess). I have started to make a new pancake-coil jig to be able wind them much easier, my last one was done by hand on a spool made of old LP records.. It didn't work very well!

The fibre-glass type mesh as seen on a coil on your site, seems to work quite well? I can find that material here fairly easily. Is that your latest in-between insulation material, is there anything better?

Thankyou Pancake Master-Chef.

[grizli]

I am indeed using Silicone moulds, but you are correct - finding them is difficult. A few years back every kitchen store here in USA was selling them for cakes. But eventually everyone learned they are horrible for making cakes. Yes, they demould easily, but pour in cake batter and try to move it. You will have cake on the floor instantly, down the cabinet - or worse, very worse, in the bottom of the hot oven. Literally they vanished from the market, with exception of some very expensive stores.

I have made more than 100 Pancake Coils in wooden boxes before I found something that made nice moulds. You must constantly search in your area. There are some baking pans with removeable bottoms, "Spring Form Pans" in english. They work well enough, and can be found in Europe too but I don't know the name.

The problem even with Silicone - they are not deep enough. A flat spiral of around 250mm diameter should have at least 75mm of insulation (wire in centre) if not 100mm for best results.

Need to find a country that makes very thick cakes. Where are people the most fat? Ah, USA. But they're aren't here either!

so i use classic metal mould and hehe thick aluminum foil, so when coil is hardened it goes easily from mould but than when I remove all aluminum foil, surface is not smooth , but who cares.... if it works ok...

I have been using only paraffine with about 5-10 percentage of beeswax to prevent breaks of paraffine which is rigid..

hehe about silicone moulds, my pancake is 7-8 cm thick so , I doubt so fat cakes are baked anywhere, without stupid hole in the middle and without flat round surface..

[barbosi]

I think is time to draw a separation line in this "pancake" coil concept.
Monofilar pancake coil was well known before Tesla knew how to tie his shoes and it was known as "spiral coil".
Tesla patented his bifilar "pancake/spiral" coil for good reasons he described in the patent.
He presented the monofilar coil in his patent for the sole reason of comparing of what he did with the same amount of wire on the same excitation and what are the benefits of his approach.
In time, folklore put under the term "pancake coil" both kind of coils. Doing so the flat outlook of a coils but in completely in two different instances (monofilar vs. bifilar) is not fair nor accurate.
I also think is fair from the people I greatly admire for their great work, is to specify if the pancake coils are monofilar or bifilar.
And if I stepped in this issue, just to clarify terms, a bifilar coil as coined by Tesla is a coil as described in patent, period. It is not made of two twisted wires (there are too many people building Bedini's SSG fantasising about Tesla's concept implemented in Bedini's motors).
Regards.

[jeff_behary]

Bifilar Coils

I think is time to draw a separation line in this "pancake" coil concept.
Monofilar pancake coil was well known before Tesla knew how to tie his shoes and it was known as "spiral coil".
Tesla patented his bifilar "pancake/spiral" coil for good reasons he described in the patent.
He presented the monofilar coil in his patent for the sole reason of comparing of what he did with the same amount of wire on the same excitation and what are the benefits of his approach.
In time, folklore put under the term "pancake coil" both kind of coils. Doing so the flat outlook of a coils but in completely in two different instances (monofilar vs. bifilar) is not fair nor accurate.
I also think is fair from the people I greatly admire for their great work, is to specify if the pancake coils are monofilar or bifilar.
And if I stepped in this issue, just to clarify terms, a bifilar coil as coined by Tesla is a coil as described in patent, period. It is not made of two twisted wires (there are too many people building Bedini's SSG fantasising about Tesla's concept implemented in Bedini's motors).
Regards.

For me I have similar views but opposite maybe...

Tesla's patent for the bifilar coil US512,340 (for me anyway) is way of producing an electromagnet without the self-induction that normally causes a back-emf arc at the contacts when the circuit is broken.

In history I've seen Tesla Pancake coils always as the single or multilayered spiral high frequency coils, used in X-Ray apparatus and other novel devices.

I think the bifilar coils need a new name. Tesla called them "Coil For Electromagnets". Maybe we could add "Bifilar" to the title...??

[morpher44]

bifilar

without the self-induction

It seems to me that the bifilar trick is appropriate for flat spiral coils
OR cylinder coils, or various other geometries as well.

By wiring up one exit wire to the other entry wire, you essentially
separate the windings by a distance of N turns rather than having
them be next to each other.
The non-bifilar has a LARGER capacitance at each turn ..
which can breakdown and arc
if the windings are close and the voltage is high.
You could extend this principal to the secondary air-coil cylinders that people
make for Tesla coils -- although I don't think people bother.

Here is an interesting bifilar pancake coil demo:
YouTube - Comparison of Tesla Bifilar and Pancake Coils