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Author Topic: what happens between a teslacoil the battery the incadescent bulb and the ground  (Read 41415 times)

woopy

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Hi everyone

some days ago Tinselkoala made an experiment with his Teslacoil, where he could light a 120 volts incadescent bulb from one of the battery terminal (no matter + or-) and his finger or the ground.

here the 2 TK's videos, thank's for sharing.

https://youtu.be/WV3posVDqJs

https://youtu.be/S_URR6Bk9cg

As you notice the bulb is much more strong on the battery terminal than the same bulb connected to the main grid.

If i have correctly understood,TK sayd that he think that the power comes from the battery, but "what is the circuitery ?"

So as i got a mini Teslacoil, i replicated the experiment and i also could light a 220 incandescent bulb connected on one terminalof a very small (450 mA) 6 s (22 volts) lipo, and the ground of my grid.
My bulb is far not so bright as TK's, but my Teslacoil is also much smaller and is a very cheap singing coil  from China and is perhaps not very well tuned.

Here the video

https://youtu.be/ZDFEevnkuq0

As you can see on the scope, the voltage around the Teslacoil increases a lot when the bulb is connected between the terminal of the battery and the ground.

As you can also see at the end of the video, when i approach my finger on the battery, the bulb fades ? As if my body mass is in opposition with the ground of the grid, and cut the effect ??

I tried to measure the current with a clampmeter, but no way the frequency is far too high (about 3 MHz), so i tried the analog ampmeter but i doubt of the value which seems to show less current when the bulb is connected.
Today i retested without the ampmeter, and the result is even  better (probably less resistance without the meter ).

Just for info, i was holding the positiv lead to connect to the battery (the bulb was not connected) and due to a bad insulation of the crocodile clip, i got a nice but painfull burning on one of my finger. So i suppose that i played the role of the bulb in this particular case ??

Another info i did, as TK did , connect the bulb directly to the + and - of the 24 volts battery, and the bulb'  filament is nearly rosa.(almost nothing)

I have no idea of what is going on in this experiment.

So my question to TK and all of you, how can we explain this effect ?

Thank's

Laurent

gotoluc

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Bonjour Laurent

The below addition should work for accurate power measurements. The capacitor value may be smaller but must be large enough to maintain a flat DC Voltage across the current sensing resistor (CSR) which is checked by your scope.
You can use a 1% 1 Ohm or 1% 0.1 Ohm as CSR.
If the voltage is flat DC across the CSR then your amp meter should measure accurately so all you need to know is the battery voltage x amps = watts

Let me know if you need anything.

Regards

Luc

gotoluc

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Laurent

I made an alternative circuit connection for your bulb in case the capacitor filters out the effect.
However, looking at it now I don't see what difference this would make but worth a try if it does.

Luc

TinselKoala

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1. The SSTC and experiments shown in my videos that Woopy linked above can be _dangerous_. As Woopy already found out, you can get painful RF burns from touching the wrong place and/or the wrong way. There is also an unresolved issue about X-ray emissions from the bulb experiment. I've stopped doing this experiment until I can learn more about the possible X-ray emissions.

2. This particular SSTC circuit is auto-resonating by virtue of E-field feedback through an antenna. This means the coil will automatically snap into resonance and will remain in resonance in spite of drawing arcs, lighting bulbs, varying external capacitance around the coil, etc. The resonant frequency of the coil changes from all these variations but the circuit follows the variations and automatically adjusts to keep the coil in resonance and making a strong E-field. I don't know how adding large external capacitance to the primary circuit will affect this feedback system.

3. There is no way that I would connect a DSO directly to this circuit. Don't blame me if you blow out your oscilloscope! You can easily detect the coil's resonance simply by suspending a scope probe 1 meter away from the coil, with a resistor across the tip and ground of the probe, or a bit of aluminum foil connected to the probe. But I would be very leery about directly connecting the digital scope for current measurements, etc. as in the above drawings.

4. I also don't know what effect this experiment has on the batteries powering the coil. I do know that there is a lot of HF noise on the power leads (the little toroid choke I have on the power leads gets quite hot when operating the coil, whether from batteries or from my PSU.) Similar circuits have been blamed for killing batteries. Remember that lead-acid batteries can evolve hydrogen gas when charging/discharging, and this circuit makes sparks and arcs.... And knowing how LiPo batteries can explode, I would not even consider running this circuit from LiPos, at least not inside the house.

So have fun, but play safe and don't get burned !

ramset

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Recent concerns about these experiments came from here ,as well as possible solutions for protection.

http://overunity.com/15999/the-eric-dollard-lightglobe-experiment/new/#new

woopy

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Hi TK

Thank's for your advices

I am surprised that this small singing Tesla coil toys which are normally sold to everybody with a 24 volts psu and a cable to connect a sound device, coul be dangerous and could emitt x-ray. But perhaps the bulb is the emitter ?? and without the bulb there is no problem at all.

What i have noticed so far:

When the TC is connected to the 24 volts psu, the bulb is less bright compared to direct connection to battery.

If i put a flat coil on top of the battery and this flat coil is connected to an antenna, the bulb is less bright.

when i put a big heavy battery (connected to nothing but forming a mass) on top of the small powering batteries, the bulb is less bright

so it seems that the less mass or antenna around the battery the better the ground connection light the bulb. It is why i suppose that the wiring around the 24 volts psu make a nice antenna and decrease the effect ??
Voila for todays consideration

Hi Luc

Thank's for the shematics
But as you can see there is a lot to test for better grasping the effect and before going on precise measurement and TK is probably right concerning a direct connection of the scope into the circuit

hope this helps

Laurent.





TeslaScientific

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Hello. The circuit is unnecessarily complicated which results in confusion. A Tesla coil, as Tesla designed it, is intended to output the energy from the GROUND end of the coil through the earth, or whatever medium. That's where the coil output is, not the top end. The capacitance terminal is supposed to SUPPRESS radiation and prevent energy from escaping, including suppressing sparks which represent wasted energy.

These circuits have the ground end of the coil connected back into the circuit which is completely the wrong way to go about it if it's intended to operate as an actual Tesla coil, because that's where the load or transmission medium is supposed to go. I would recommend using a simple variable frequency oscillator with an amplifier of whatever power to drive the primary coil. This leaves the secondary completely free to do the job it was intended to do, which is output useful energy via a single wire/terminal at the ground end, and avoids confusion caused by inadvisable circuit configurations.

http://www.youtube.com/watch?v=zq7xSG91YCg

http://www.youtube.com/watch?v=EDU5Pe9wr8g

http://www.youtube.com/watch?v=DovunOxlY1k

endlessoceans

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Hi everyone



I have no idea of what is going on in this experiment.

So my question to TK and all of you, how can we explain this effect ?

Thank's

Laurent


Hi Laurent

Very easily explainable and replicable.  Firstly 4 Watt load is very small otherwise the filament will not glow.   This is a HF HV circuit.  Which simply equates to a LOT of energy being lost/transmitted through the topload.  So where do you think this energy goes?  By attaching to the ground or the terminal of the battery you are merely completing the circuit and you have a closed circuit again.   
This circuit and coils have minor configuration difference but it behaves much like a joule thief with the same limitations.

You just have to be respectful of the HV HF and dangers for your fingers.  ;D

You can perform same thing at lower more respectful voltage without all the losses.  In fact many of your former experiments you have done this without realising.  Just coming full circle on another configuration. 

Interesting but not OU.   Classical Tesla tech.




woopy

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Hi Teslascientific and Endlessoceans

Thank's for input

Youp what is correct ?

Ts    says that in a teslacoil the energy should  go from the ground (bottom) of the coil to the earth or else. And the tophead  cap should be calculated to prevent as much as possible the radiations or losses in order to concentrate a max of power  on the  ground part of the coil.

 Eo    says that the energy irradiate from the tophead of the coil all over the place so , by touching the battery terminal with the bulb and main ground, we simply close the circuit. So far i understand  the power should comes from the top of the coil.

Both answers  seems some how contradictory or am i missing something?

Laurent


forest

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I think both is correct.Tesla first wanted to send energy via upper strata, then one day he found stationary waves in Earth crust.
For our purpose it is important to avoid both methods ;-)

ramset

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Apologize for the intrusion !




TeslaScientific

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Hi Teslascientific and Endlessoceans

Thank's for input

Youp what is correct ?

Ts    says that in a teslacoil the energy should  go from the ground (bottom) of the coil to the earth or else. And the tophead  cap should be calculated to prevent as much as possible the radiations or losses in order to concentrate a max of power  on the  ground part of the coil.

 Eo    says that the energy irradiate from the tophead of the coil all over the place so , by touching the battery terminal with the bulb and main ground, we simply close the circuit. So far i understand  the power should comes from the top of the coil.

Both answers  seems some how contradictory or am i missing something?

Laurent

Hi woopy.

Despite what others may say, it is operating as a standard Tesla coil. The coil will have a 1/4 wave resonant potential and current distribution over it. This means that the maximum current is at the GROUND end of the coil. Maximum potential is at the FREE end of the coil. That's why the sparks come from the free end. The current is at the opposite end of the coil, 90 degrees, or 1/4 wavelength, out of phase.

https://maritime.org/doc/radio/img/fig142.jpg

Hence, when the ground end of the coil is connected back into the circuit for "feedback" due to not using a proper variable frequency oscillator, all the energy is being sent back into the circuit, so no wonder you are lighting incandescent bulbs off the battery terminals. In a similar manner is how Tesla blew up the substation at Colorado Springs, he was inadvertently sending RF back down the power line.

If you want to understand what's going on then I would advise you to simplify the whole thing and remove the unnecessarily complicated circuitry. Isolate the effect. Drive the primary with a simple high frequency AC source and the secondary will work as intended, the effect has nothing to do with the batteries or the circuit, that's what a Tesla coil is SUPPOSED to do.

It's a SINGLE wire single terminal transmission system. There is no "ground loop" or "closed circuits" through air gaps. It's exactly like the AT&T/Bell Labs video shows. The waves reflect/oscillate back and forth along the transmission line/structure, and that's why the bulb lights with one wire, not because of imaginary closed circuits. It's not necessary to form a closed circuit.

Quote from: Nikola Tesla
You see, the apparatus which I have devised was an apparatus enabling one to produce tremendous differences of potential and currents in an antenna circuit.  These requirements must be fulfilled, whether you transmit by currents of conduction, or whether you transmit by electromagnetic waves.  You want high potential currents, you want a great amount of vibratory energy; but you can graduate this vibratory energy.  By proper design and choice of wave lengths, you can arrange it so that you get, for instance, 5 percent in these electromagnetic waves and 95 percent in the current that goes through the earth.  That is what I am doing.  Or you can get, as these radio men, 95 percent in the energy of electromagnetic waves and only 5 percent in the energy of the current. . . . The apparatus is suitable for one or the other method.  I am not producing radiation with my system; I am suppressing electromagnetic waves. . . . In my system, you should free yourself of the idea that there is radiation, that the energy is radiated.  It is not radiated; it is conserved.

http://www.tfcbooks.com/tesla/nt_on_ac.htm

TinselKoala

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Half right, almost all wrong.

1. The feedback system of this coil does _NOT_ depend on the bottom of the secondary being connected back to the circuit, like in Kacher/Slayer circuits. The feedback comes through an antenna which is picking up the oscillating E-field produced when the secondary is in resonance. The system works even when the bottom of the secondary is disconnected from the driver circuit's negative rail and is connected to true Earth ground instead.

2. A fixed frequency oscillator will require constant tuning if the secondary is to stay in resonance while drawing sparks, powering loads, etc. This is because the actual resonant frequency of the secondary+load changes during these manipulations. A little research will show that the most successful SSTCs will either use a phaselocked loop circuit or antenna>CMOS gate>driver chip or similar circuit so that the frequency of the driver is always automatically keeping the secondary in resonance as its frequency changes due to loads, environment, etc.

3. Compare the circuit board and schematic of this coil, with what is posted above. Which is truly simpler? Count the parts. Which is smaller? Mine sits on a footprint that is 8 inches x 5 1/2 inches, half the size of a standard sheet of typing paper, not including the batteries. It's fully portable, can be easily taken out of doors, and requires no mains connection, no external signal generator, no actual earth ground.


Yes, it is working as a 1/4 wave resonator producing Voltage Rise by Standing Wave Resonance. That much, at least, is correct. Note that the primary has only 3 turns, is driven by a single mosfet switching 24 volts, and has no power-wasting resistors in the circuit.

Someone else "explained" that the effect I showed is due to power being reflected from the top capacity back into the drive circuit. The only problem with this "explanation" is that the demonstration works the same, with or without the top capacity on the secondary.

TeslaScientific

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2. A fixed frequency oscillator will require constant tuning if the secondary is to stay in resonance while drawing sparks, powering loads, etc. This is because the actual resonant frequency of the secondary+load changes during these manipulations. A little research will show that the most successful SSTCs will either use a phaselocked loop circuit or antenna>CMOS gate>driver chip or similar circuit so that the frequency of the driver is always automatically keeping the secondary in resonance as its frequency changes due to loads, environment, etc.

It doesn't require constant tuning. It requires tuning once. Which is done deliberately to a specific frequency, and not some arbitrary frequency. That's point #1 about learning and engineering. When the coil is tuned with a sufficiently large ground capacitance, the relatively small capacitance of the load doesn't make any difference. The coil is already tuned to maximum output. There's no reason to retune it. As for loads connected directly to the coil output without such a capacitance or transmission medium, those are "experimental" conditions in which adjustments are to be expected, and it's not very difficult to press a few buttons or turn a knob and tune it to the new, temporary frequency. What's more, the primary capacitor should also need adjusting.

3. Compare the circuit board and schematic of this coil, with what is posted above. Which is truly simpler? Count the parts. Which is smaller? Mine sits on a footprint that is 8 inches x 5 1/2 inches, half the size of a standard sheet of typing paper, not including the batteries. It's fully portable, can be easily taken out of doors, and requires no mains connection, no external signal generator, no actual earth ground.

The point is the simplicity of the approach. You simply connect the primary coil to the power supply, and that's it. The coil has no interaction with any other circuitry, no feedback antennas or any unpredictable variables. Also I might point out that the circuit is simply an op amp circuit and not much could be simpler than that. It also has a modulator at the first stage to enable amplitude modulation with audio input which isn't necessary at all for its operation. You may notice that the board is in 3 sections. That's because it's a modular/3 stage amplifier, and any one stage can work alone or together. I can also remove the output resistors if I like, but I choose to match it to the primary coil impedance. But I'm not sure that it's necessary to get into a competition over output impedance.

The primary has 2 turns. Secondary 17 turns. Extra coil 100 turns.

Someone else "explained" that the effect I showed is due to power being reflected from the top capacity back into the drive circuit. The only problem with this "explanation" is that the demonstration works the same, with or without the top capacity on the secondary.

I'm sure it does work the same. But that's not quite right. A wire end is a termination. There's a change in impedance. It's an open circuit. Hence the wave reflects back from whence it came, which is back down through the coil. Of course, a wire is an efficient radiator of energy which is why they're used as radio antennas all over the place so more energy is radiated than would be if there was a large capacitance, but the coil is in resonance BECAUSE the wave is reflected and forms a standing wave distribution along the coil. If the wave wasn't reflected back down the coil then it could never resonate.

Either way, if the circuit works without the ground end of the secondary being connected back into the circuit, then that's the advisable way to use a Tesla coil since that's supposed to be the output of the coil.

So my question to TK and all of you, how can we explain this effect ?

.

forest

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This fight will never stop ,unless somebody show that Tesla coil can be used in 2 or 3 completely different modes of operation. That is the reason people cannot replicate Tesla findings. Confusion.
Would be VERY VERY IMPORTANT to scale down TeslaScientific Tesla coil and compare the results with RF version. I do believe this is not RF exactly like Tesla said.