Tesla's Magnifying Transmitter "Replications"

[Farmhand]

For instance I counted the turns in my coils and calculated the wire length of
the secondaries, it turns out to be approximately 273 meters and it's
inductance is roughly 8.6 mH from memory and with the three different terminal
arrangements (capacities) I get three different resonant frequencies with the
smallest terminal capacitance I get about 485 Khz add another ring to the
terminal and it's 470 Khz another one which causes a big increase and its 430 Khz
to keep the primary resonant I adjust its charging inductance and capacitance.

To keep the receiver resonant it gets the same terminal and the same primary tuning.

The 275 meters is a lot more wire than the regular calculator would say for
that frequency range. Working it out on the highest frequency I get with the
smallest capacitance it is say 480 Khz this calculator says the 1/4 wavelength is 156 meters but I need at least
273 with 5.6 pf or so added by the terminal. If I used only 156 meters the
frequency would be higher and could be worked out roughly by this calculator
using the method i described above.

So for a given frequency say 480 Khz I need to use more
than the wire length indicated by the regular calculator and it is dependent on
the way the coil is wound as well as the added capacitance of the terminal
and/or surroundings.

Going back to the 20400 Hz frequency I said above 20400, is a multiple of 60
and 12, and much more of course, 6800 is 1/3 of that and 4080 is 1/5, so
there are a lot of options. We shouldn't limit ourselves except to what we
want. Those two frequencies 6800 and 4080 are favorite roundabout
frequencies for me they seem to work well with my other stuff which is a
coincidence I hadn't thought of till just now.

As the input frequency is lowered the Overtones or harmonics or whatever
show up and can be easily tuned to. By scope and output at the receiver.

Cheers

[Farmhand]

Here is a drawing showing the tuning/adjustment I have in my LV setup.

Transmitter


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Receiver


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The circuits are almost identical except for the switch and the primary cap at
the transmitter, however I've found that the tuning cap value can be used for
the charging cap and the tuning cap dispensed with which seems to work
much the same ( the receiver tuning cap must remain ).

Although when using the lower frequencies the above arrangement works well.

..
Now to the transformer coupling in my little HV setup.

This is how I am coupling the LV transformer to the HV transformer without
coupling them correctly I don't get enough to run the gap . I chose 40 Khz
because it seems the HV secondary with the HV primary caps is about that.
Close to NST frequency too.



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.

On a side note, Everybody, if we could keep in mind that some people have
slow internet connections and if we stick to using thumbnails for pictures it
will help the pages load faster for them. I think the main thing is the file size
even a big picture if it has a small file size will load ok. A page full of high
quality large photos takes forever to load on a slow connection. I am guilty of
this myself and will try to limit the large pictures I embed, linked photos can
be High quality and big if we want so maybe an alternative link for big pics
where detail is wanted to be kept.

Thanks
Cheers

[Farmhand]

Hi all, I think this is what Nikola means by the Earth should be an "odd multiple
of the 1/4 wavelength of the electrical disturbance in the circuit" .



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In the drawing below I used 3 x 1/4 wavelengths for the connecting
conductor (medium) not natural. It could be 1/4, 3/4, 5/4, 7/4. as long as
its an odd multiple. The coil is 1/4, the transmission distance 3/4. Then the
receiver is 1/4, and the transmission distance back is 3/4. With the
transmission medium at 3 x 1/4 wavelengths it would be a T1-2-3-4-R1-2-3-4 type beat, as far as 1/4 wavelengths go.



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I don't see why we can't use a wire or transmission medium that is resonant
at an odd multiple of the 1/4 wavelength of the electrical disturbance of our
circuit, and get good transmission results.

I also think the extra coil "B" should have an odd multiple 1/4 wavelength
relationship with the Secondary coil "A" but I haven't wrapped my head
around that yet. Though I have an idea and am in the process of testing it
before I commit to winding any big coils. P.S. Both the coils "A" and "B"
together still need to be 1/4 WL of the electrical disturbance though.

Cheers

[Farmhand]

OK it works I tried it with my LV setup.

It seems to work well, I now get a consistent 55 volts in the DC cap at the
receiver while powering the 6 LEDS at crazy brightness through 1270 ohms of
resistors.

The big coil of yellow cable is the virtual Distance ( planet VP470 ) The wave form
on the scope is from it the FG has the frequency on it.


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So on paper it looks like this for my LV solid state setup. Seems a bit more
efficient to. And easier to keep on the rise.


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[dR-Green]

Hey Farmhand. I'm not quite sure what's going on here now. Lots of numbers being thrown about Just checking in to say I'll be taking a closer look and trying to understand it a bit later. Lots of work to do now. I've assembled the frames for the new coils, and while I'm at it I decided to get all the pieces for the 60cm spirals done/glued together as well. So I'll be back in a bit to try and understand all this

[lamare]

Hi all, I think this is what Nikola means by the Earth should be an "odd multiple of the 1/4 wavelength of the electrical disturbance in the circuit" .

<snip>

I don't see why we can't use a wire or transmission medium that is resonant at an odd multiple of the 1/4 wavelength of the electrical disturbance of our circuit, and get good transmission results.

I also think the extra coil "B" should have an odd multiple 1/4 wavelength relationship with the Secondary coil "A" but I haven't wrapped my head around that yet. Though I have an idea and am in the process of testing it before I commit to winding any big coils. P.S. Both the coils "A" and "B" together still need to be 1/4 WL of the electrical disturbance though.

Cheers

You can also read Tesla's statement here, which was written in 1906:
The Tesla Magnifying Transmitter

Stated otherwise, the terrestrial conductor is thrown into resonance with the oscillations impressed upon it just like a wire. More than this, a number of facts ascertained by me clearly show, that the movement of electricity through it follows certain laws with nearly mathematical rigor. For the present it will be sufficient to state, that the earth behaves like a perfectly smooth or polished conductor of inappreciable resistance, with capacity and self-induction uniformly distributed along the axis of symmetry of waves propagation and transmitting slow electrical oscillations without sensible distortion and attenuation. Besides the above, three requirements seem to be essential to the establishment of the resonating condition.

1. The earth's diameter passing through the pole should be an odd multiple of the quarter wave-length, that is, of the ratio between the velocity of light and four times the frequency of the currents.

2. It is necessary to employ oscillations, in which the rate of radiation of energy into space in the form of Hertzians or electromagnetic waves is very small. To give an idea I would say, that the frequency should be smaller than twenty thousand per second, through shorter waves might be practicable. The lowest frequency would appear to be six per second, in which case there will be but one node, at or near the ground plate, and, paradoxical as it may seem, the opposite the transmitter. With oscillations still slower the earth, strictly speaking, will not resonate, but simply act as capacity, and the variation of potential will be more or less uniform over its entire surface.

3. The most essential requirement is, however, that irrespective of frequency, the wave or wave train should continue for a certain interval of time, which I have estimated to be not less than one twelfth-or probably 0.08484-of a second, and which is taken in passing to, and returning from the region diametrically opposite the pole, over the earth's surface, with a mean velocity of about 471,240 kilometers per second......"

Note that he estimates a velocity of 471,240 kilometers per second for the surface waves he was using. And this tells us exactly what kind of waves he was using: longitudinal surface waves, which can likely also be described with the formula for Schumann resonances, as I posted earlier for the transverse case:

As I posted, I found out that the transverse surface wave across the sphere can be expressed with the theoretical formula for Schumann resonance:

Schumann resonances - Wikipedia, the free encyclopedia

f_n= c/(2*pi*r) * sqrt(n(n+1))

I calculated the diameter for a 1/2 lambda sphere using Dollard's formula that the speed of longitudinal waves is pi/2 times c, but then the corresponding Schumann resonance frequency turned out to be 1287 MHz, which should be 1296 MHz if Eric's formula is correct.

So, I compared the Schumann formula with the formula for resonance in a string, basically a 1/2 lambda resonance with closed ends:

f_n = (n * c_l)/ 2L

Since L = 2r, we can now calculate the theoretical speed c_l. When we take n=1 in the string formula and n=2 in the Schumann formula, we end up with matching resonance frequencies.

Since n(n +1) equals 6 for n=2, we get:

c_l / (4 * r) = c_t / (2 * pi * r) * sqrt(6)

This works out to:

c_l = 2/pi * sqrt(6) * c_t

This computes to 1,559393604, while pi/2 computes to 1,570796325, a difference of 0,7%.....

So, now we have a theoretical derivation for the longitudinal wave speed, which turns out to be just a tiny bit lower than Eric's pi/2...

Depending on what c you use, the longitudinal or the transverse, I assume you get the different longitudinal and transverse surface resonance frequencies for your particular (ideal hollow) sphere. When using the normal c, it turned out that when I would take a diameter of 1/2 lambda longitudinal, I get a nice transverse surface wave along with the "trough the interior" longitudinal 1/2 lambda resonance...

As you can see, the Schumann resonance formula includes a factor sqrt(n(n+1)), which goes to n for sufficiently large n, as in the case you are working in the kHz range on the whole Earth.

All right, so with an earth diameter D, we get a circumference pi*D. So, if the diameter is an odd multiple m of 1/4 lambda transverse (speed of light), we get a corresponding m * pi * 2/pi * sqrt(6) = m * 2 sqrt(6) = m* 4,8989. When we divide this by 4, we get m * 1,2247 corresponding longitudinal wavelengths across the surface, almost m * 5/4. Very confusing, especially if you do not know Schumann's formula, as was the case when Tesla did his experiments. Wikipedia again:

This global electromagnetic resonance phenomenon is named after physicist Winfried Otto Schumann who predicted it mathematically in 1952

And this gets even more confusing if you totally reject the existence of transverse "Herzian" waves, as Tesla did.

However, Tesla also said this in 1922:
Nikola Tesla On His Work With Alternating Currents -- Chapter IV

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. . . .

This "current that goes through the earth" would be this longitudinal surface wave, of course. So, it is distinctly different from the idea of a current consisting of electrons going trough the earth (or a wire). This current is essentially a mass-free wave traveling across the surface of the earth (or just outside your wire), whereby electrons traveling back and forth trough the Earth (or wire) itself should be considered more like unwanted losses than as doing anything good. The only good they do is that they allow you to create these energy transporting longitudinal waves at the transmitter and to turn the energy back into usable "real" electron-based current at the receiver.

All right. Let's first take a look at all the possible resonances in a sphere like the Earth. There are two kinds of waves: longitudinal and transverse. And there are two ways by which these can propagate trough a hollow sphere: trough the interior and along the surface. So, we got ourselves 4 distinct resonance modes a hollow or non-perfect conducting sphere can support. And you have to keep these properly apart when you want to study or describe these kind of phenomena.

Now that we understand Schumann's formula, it is clear that Tesla's TMT can only work when there are a whole number of longitudinal wavelengths across the surface of the Earth, because otherwise you will not get resonance since the surface of the earth is kind of a closed loop, just like a loop antenna.

Now if you want to use a wire (or coil) in the place of the Earth and you want to mimic Tesla's TMT, you do want to make sure that you take your wire a whole number times 1/2 longitudinal wavelength for your chosen frequency. You can take 1/2 lambda with a wire, because as far as I can tell it doesn't matter wheter or not transmitter and receiver are in phase when they are not radiating into space and you want to make sure you have longitudinal waves along your resonating wire, because a transverse resonating wire radiates like a properly designed antenna. Not a good idea...

That means calculating with the longitudinal propagation speed 2/pi * sqrt(6) times c (or pi/2 times c, which is practically the same). And in your calculations you should also account for the fact that waves traveling along wires travel slower than trough free space. For an unshielded wire, you can calculate with a speed factor of about 0.95. For a coax cable, this factor is specified and lies around 0.6 - 0.85 or so. For insulated coil wire, I would guess something less than 0.95, maybe 0.9 or so.

Also see: http://www.energeticforum.com/renewa...tml#post166020

And if you load your coil with a top sphere, you do want to make sure it radiates as little as possible, which means it should definitely not resonate. As far as I can tell, longitudinal surface waves across a sphere (and along a wire ) are not such a problem, because these apparently don't radiate into space, because otherwise neither Tesla's TMT nor his one wire system would have worked.

Longitudinal resonances trough the interior are a problem, because depending on the particular mode (1/4,1/2,3/4,1/1 longitudinal lambda), you either get a nice radiating longitudinal antenna, OR a nice radiating transverse surface wave and thus transverse antenna.

And transverse surface waves are a problem, but as far as I can tell, these are coupled to interior longitudinal resonances, so you can do with the Schumann formula for those.

As far as I can tell, the Schumann formula is the most accurate for calculating your transverse resonances, while the string formula posted above is the most accurate for calculating your n * lambda longitudinal problem frequencies (when using the longitudinal propagation speed, of course).

So, you want to take the diameter of your sphere such that it is not close to a multiple of a longitudinal wavelength, and you want to use the Schumann formula to make sure that the diameter is such that there is no transverse Schumann resonance frequency near your operation frequency.

You can play with the Schumann formula in my spreadsheet:
http://www.tuks.nl/Spice/lamare_dipole_calc_v2.xls

I guess that pretty much sums up "proper design and choice of wave lengths"

[Farmhand]

Hi dR, I just created a "virtual" distance and capacity of 470 meters or so
which is 3 x 1/4 wavelength. The transmission distance is important too. If
the transmission distance is wrong the receiver won't get resonant
transmission.

As it turns out my wire was way too short to be an odd multiple of the 1/4
wavelength and therefore resonant at at an odd multiple of the 1/4 WL, so by
adding the correct capacitance to it it now behaves as if it were 470 or so
meters long. It's an improvement in transmission efficiency. And shows that
the wire needs to be a specific length to work properly.

When we see videos of setups with the receiver right next to the transmitter
it means next to nothing, because of direct coupling capacitively or
otherwise.

If I put the receiver right next to the transmitter it will work without the wire
connection which is not much different to lighting a fluro from the terminal. To
show transmission through the wire the coils in my opinion should at least be
far enough apart to show no output without the wire. For me using only 12 volts
that is about 3 meters, any closer and the transmitter starts to interfere with
the receiver in ways it shouldn't.

I think if the transmission distance is not an odd multiple of the 1/4
wavelength then the efficiency will be less because the return of unused
energy will not be ideal.

Which I think means that if a ground transmissions are done at a particular
chosen frequency the receiver needs to be positioned at a distance which is
an odd multiple of the 1/4 WL.

I checked the voltage on my LV coils and there is a steady increase in voltage
up the coil to maximum at the top of both the transmitter and receiver.

Doing what I did increase the receiver output voltage and improved efficiency
but the output power is still about the same, input is less.

Cheers

[Farmhand]

Hi lamare,

By proper design and choice of wavelengths I take it to mean if the wavelength
is too short a lot of Hertz wave radiation is assured, if the wavelength is long as
Tesla says it should be, the Hertz radiations are less as he states in the patent.
There is no escaping that. The higher the frequency gets above 25-30 Khz the
more Hertz radiations there will be as losses. So to reduce that as much as
possible the frequency should be low. This is why I am lowering my frequency
more and more.

I did read the patent and linked it already.

I wasn't trying to mimic a Magnifying transmitter as such, I was merely doing
an experiment to show to myself the importance of the odd multiple
wavelength distance. That's all. I think I did what I was trying to do.

Tesla says the diameter from pole to pole must be an odd multiple of the 1/4
wavelength based on C, as the currents are propagated around the Earth and
not directly through it they would need to propagate faster than C for that to
work.

However I don't have a sphere I have a wire. And I have gone as far as I can
with this without actually building a full size Magnifying Transmitter.

I have good results, and can transmit from inside a steel shed to inside
another steel shed they could be two Faraday cages and it wouldn't make
much difference because the currents are transmitted through the wire.

From this point on there will be very little further input from me to this thread if any.
Very few of us have shown our results. So I am stepping aside. I'll bee back
when I have a few million dollars to build a full size one.


Please continue.


Cheers

P.S. Some of the drawings I made may be a bit off the one showing the
waves and the receiver 90* out of phase is wrong about the receiver phase I
think, I think it should be in phase or out 180* either same polarity or opposite.

..

[lamare]

Hi Farmhand,

Hi lamare,

By proper design and choice of wavelengths I take it to mean if the wavelength is too short a lot of Hertz wave radiation is assured, if the wavelength is long as Tesla says it should be the Hertz radiations are less as he states in the patent.
There is no escaping that. The higher the frequency gets above 25-30 Khz the more Hertz radiations there will be as losses. So to reduce that as much as possible the frequency should be low. This is why I am lowering my frequency more and more.

He does not say the wavelength should be long. He talks about multiples, which can certainly mean high multiples. And I'm sure he means high multiples, because that's eventually where the magnifying effect is to be found.

What he says is that he uses longitudinal waves across the Earth. These surface waves have the nice property that they stay along the surface of the Earth or a wire and DO NOT radiate into space. And _that_ is what you want to achieve. You want waves traveling in such a way that they stay within the proximity of either your Earth or your "ground wire". It does not matter what wavelength you use, as long as you manage to get a longitudinal resonance along your wire. You see, because of the difference in propagation speed, the frequencies at which you get longitudinal resonance are pretty far away from the nearest transverse resonance frrequency. And therefore, when in longitudinal resonance, you get a nice suppression of radiating transverse waves. Of course, it's never 100%, but may be like 95% as Tesla was talking about?

Tesla says the diameter from pole to pole must be an odd multiple of the 1/4
wavelength based on C, as the currents are propagated around the Earth and
not directly through it they would need to propagate faster than C for that to
work.

The point is that the resonances going trough the interior and the ones going over the surface are tied to one another, at least in a number of cases. One of these cases is when you have a multiple of 1/2 lambda longitudinal trough the interior, which matches to a 2 lambda (IIRC) transverse surface wave. That's why my exercise with the Schumann formula allows me to derive the theoretical propagation speed for longitudinal waves.

So, the problem is to make sure that you get the right resonance mode at any component in your system. Your loading spheres should not resonate, because if they do they radiate, and your resonating wave guide, either your Earth or your wire, should be in a longitudinal resonance mode, because apparently longitudinal waves along either the surface of a sphere or the length of a wire DO NOT radiate.

Otherwise neither Tesla's TMT nor his one-wire system would have come even close to working!

Update: You may want to check out this paper by Elmore, who explains how this longitudinal mode along an unshielded wire works:
http://www.tuks.nl/pdf/Patents/Elmor...0Conductor.pdf

[Farmhand]

Hi Farmhand,



He does not say the wavelength should be long. He talks about multiples, which can certainly mean high multiples. And I'm sure he means high multiples, because that's eventually where the magnifying effect is to be found.

What he says is that he uses longitudinal waves across the Earth. These surface waves have the nice property that they stay along the surface of the Earth or a wire and DO NOT radiate into space. And _that_ is what you want to achieve. You want waves traveling in such a way that they stay within the proximity of either your Earth or your "ground wire". It does not matter what wavelength you use, as long as you manage to get a longitudinal resonance along your wire. You see, because of the difference in propagation speed, the frequencies at which you get longitudinal resonance are pretty far away from the nearest transverse resonance frrequency. And therefore, when in longitudinal resonance, you get a nice suppression of radiating transverse waves. Of course, it's never 100%, but may be like 95% as Tesla was talking about?



The point is that the resonances going trough the interior and the ones going over the surface are tied to one another, at least in a number of cases. One of these cases is when you have a multiple of 1/2 lambda longitudinal trough the interior, which matches to a 2 lambda (IIRC) transverse surface wave. That's why my exercise with the Schumann formula allows me to derive the theoretical propagation speed for longitudinal waves.

So, the problem is to make sure that you get the right resonance mode at any component in your system. Your loading spheres should not resonate, because if they do they radiate, and your resonating wave guide, either your Earth or your wire, should be in a longitudinal resonance mode, because apparently longitudinal waves along either the surface of a sphere or the length of a wire DO NOT radiate.

Otherwise neither Tesla's TMT nor his one-wire system would have come even close to working!

Update: You may want to check out this paper by Elmore, who explains how this longitudinal mode along an unshielded wire works:
http://www.tuks.nl/pdf/Patents/Elmor...0Conductor.pdf

Lamare I am talking bout the wavelength of the electrical disturbance in the
circuit. Tesla states in that patent the frequency should be no higher than 20 Khz
or so, that is what I mean by long. Did you read the patent ?

(corrected from 35Khz to 20Khz.)


..

[Farmhand]

Line 40. In other documents he states as high as 35 Khz but that is maximum as
far as practical goes is what I get from the other documents, this one says 20 Khz.



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EDIT: I corrected my last post.

This patent. NIKOLA TESLA - Google Patents


..

[Farmhand]

Going by what Tesla says, with me using 470 Khz, this is far too high to limit
Hertz radiations to a few percent, I estimate i can get at best conditions 80 %
of the transmitter input to the receiver at worst less than 50 % the increased
losses are observable. And understandable considering the inventor says it will
happen with any setup even his own if he tried to use to high of a frequency.

People working in the Mhz range with higher voltages will get more radiations
than me given the same terminal quality.

Cheers

[lamare]

Lamare I am talking bout the wavelength of the electrical disturbance in the
circuit. Tesla states in that patent the frequency should be no higher than 20 Khz
or so, that is what I mean by long. Did you read the patent ?

(corrected from 35Khz to 20Khz.)


..

Yeah, read it some time ago, so I'm talking from what I remember and from my understanding of the basic principles.

When you are talking about using the Earth as a resonating conductor, you are talking about a pretty big sphere. And a sphere of any size has particular resonance modes described by the Schumann formula for the case of an ideal conducting sphere. So, this formula can be used to calculate the resonance modes of the loading spheres people are using.

You may have a point in that you don't want to use frequencies that are too high. As you can see in the Schumann formula, there is a factor sqrt(n(n+1)), which goes to 1 pretty fast. Now this formula describes the ideal case which does not describe the actual situation of the real Earth very well, IIRC.

Now if you remember how close the propagation speed of longitudinal waves is to pi/2 times c, you get to the situation pretty fast that the transverse and longitudinal resonance modes, one going trough the interior and one over the surface, always match one another. And then you can no longer choose one particular resonance mode over the other.

However, that has to do with the specific geometry of a sphere and as far as I can tell does not apply to a straight wire. So, I don't think there is a frequency limit when using a wire to connect transmitter and reciever. And IIRC Meyl was working at 2 MHz or so.

[lamare]

Going by what Tesla says, with me using 470 Khz, this is far too high to limit
Hertz radiations to a few percent, I estimate i can get at best conditions 80 %
of the transmitter input to the receiver at worst less than 50 % the increased
losses are observable. And understandable considering the inventor says it will
happen with any setup even his own if he tried to use to high of a frequency.

People working in the Mhz range with higher voltages will get more radiations
than me given the same terminal quality.

Cheers

As far as I can tell, it all comes down to designing and matching all components in the system. So, if you want to work in the MHz range, your loading spheres must be much smaller compared to what can be used in the kHz range.

At this moment, I can't say much about the minimum size of the spheres, but they have to temporary store the electrons flowing in and out of your coil, so you might run into a devil's dilemma there. Will think about that further. Using a torus-shape might also have advantages, but I will also have to think about that before I can say anything about that.

IIRC Dollard used some kind of light bulbs instead of spheres, which he referred to as "terminators":
Tesla's Longitudinal Electricity - Eric Dollard, Peter Lindemann & Tom Brown on Vimeo

[Farmhand]

Yeah, read it some time ago, so I'm talking from what I remember and from my understanding of the basic principles.

When you are talking about using the Earth as a resonating conductor, you are talking about a pretty big sphere. And a sphere of any size has particular resonance modes described by the Schumann formula for the case of an ideal conducting sphere. So, this formula can be used to calculate the resonance modes of the loading spheres people are using.

You may have a point in that you don't want to use frequencies that are too high. As you can see in the Schumann formula, there is a factor sqrt(n(n+1)), which goes to 1 pretty fast. Now this formula describes the ideal case which does not describe the actual situation of the real Earth very well, IIRC.

Now if you remember how close the propagation speed of longitudinal waves is to pi/2 times c, you get to the situation pretty fast that the transverse and longitudinal resonance modes, one going trough the interior and one over the surface, always match one another. And then you can no longer choose one particular resonance mode over the other.

However, that has to do with the specific geometry of a sphere and as far as I can tell does not apply to a straight wire. So, I don't think there is a frequency limit when using a wire to connect transmitter and reciever. And IIRC Meyl was working at 2 MHz or so.

Yes and what was the input "power" and output "power" showed by Meyl, the
terminals are more likely to radiate with higher voltages too.

Meyl used 2 volts supply I think, what was the voltage on his terminals was it
hundreds of volts ? I doubt it. But mine are. He made a big deal of there being
more than 2 volts at the receiver output.

My input is 12 volts and the receiver output with 6 x 5 mm LED's load the
output voltage is 55 - 60 volts, with only a capacitor for load it can charge
4.4 uF of caps to 800 volts from the receiver output coil. Is that not good ?
I think that is better than Meyl showed.

He lit up 2 x 3 mm LEDs in the video I seen. But what was the input power
and output power ?

Meyl probably just used a lower frequency to show a no output condition at
the receiver with a light at the transmitter on, then just go the resonant
frequency and the receiver light comes on, simple I can do it too.

You should build a setup and experiment with it.

People are free to think what they want, I think the higher the frequency the
more radiations there will be by default.

Cheers