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Author Topic: Transatlantic Telluric Communication Experiment  (Read 13084 times)

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I'm working with Eric Dollard personally this week, learning a ton in the process so I figure I'd share bits of what I'm picking up thus-far.

* Eric is extremely focused on having absolute minimum impedance to ground for telluric communication.

* His ground is a buried pair of old fuel tanks with 1 ohm measured impedance, and even that merely 'good enough'.  The wires leading from tank to shop are probably enough to drop performance substantially.  The entire coil and apparatus is eventually going to be sitting outside directly atop a set of electrodes attached symmetrically to the tank ground.

* Impedance matching transformer must also be wound to match well to the 1-2 ohm expected impedance (harder than it seems for ferrite apparently).  We've been using 61 ferrite for it's low loss characteristics, but the low mutual inductance might be hurting more than it's helping in this case.   We'll be doing a side-by-side with 43 ferrite to confirm if this is the difference.

* Ground current is preferably measured with an RF amp meter (thermocouple type).  Anything else introduces too much impedance, and current sensors can give inaccurate results.

* Extra coil impedance should ideally also match the ground.  An ideal Extra coil in this setup would probably be 1/4in copper tubing rather than wire to meet that 1 ohm requirement.


Once we're done, I intend on batching up everything together and creating a how-to guide + videos so others can more easily break into this field.  (especially the other 2-3 on this team actively working on it :P)


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Great to see you working with the Legend himself!
Tell Eric that Willie Johnson Jr. advanced his electrical theory considerably.  Took it all the way to a complete unified field theory.  In case he was not aware.
   
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@Grumpy

Tesla, only his patents are of great interest. The physics he imagined had nothing to do with reality. He was an excellent engineer, but a bad physicist and was wrong to criticize the physics of his time. This is why he failed to transmit electricity at a distance. It can be done, but at a very small distance, and it can be explained conventionally.


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Until we have a proven unified theory, physics is incomplete.  We look up in the sky and see a big universe that we cannot explore, but only watch from afar.  We look at the new images from the James Webb and this universe has more galaxies than we ever imagined.

Heaviside, et al, got rid of Maxwell's potentials, later experiments have shown them to be physically valid.  Is there any science related to these potentials that has not been developed for the last century?  Are we missing anything?

The US Congress recently implied that UFO's are not from Earth.  Can we ever travel like they appear to?

In the attached paper, "Observation of scalar longitudinal electrodynamic waves", the authors (Monstein and Wesley) claim to transmit/receive with longitudinal waves.  They are convincing, but I admittedly don't understand all of it.  Lacking knowledge, I have to rely on the interpretations of others.  This is enough to keep my attention, but further proof is desired.  I wish they had used a much higher voltage signal!  They mention a charge separation produced by a nuclear blast, but they do not state that a current could be driven in a conductor by a longitudinal wave, but still interesting.

Edit: F6 mentioned a refutation of the attached paper.  I found the refuting paper and attached it as well.


   

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Tesla, only his patents are of great interest. The physics he imagined had nothing to do with reality. He was an excellent engineer, but a bad physicist and was wrong to criticize the physics of his time.
This is why he failed to transmit electricity at a distance.

Quite a bold and ignorant claim.
I have no use for such nonsense.


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Fabricobbled a bench today out of telephone pole scrap so we could get the Tesla Extra coil positioned directly atop the ground connection.
We're up to 2 amps of ground current meaning 13 ohms measured impedance, which should hopefully be enough to pick up at some distance away.  Ground impedance here is excellent, with measured DC resistance at or below 1 ohm.

Currently coordinating to perform a 100mi test to a friend nearby tomorrow to see what we get🤞  Second station has a similar setup with a very intense ground.

Being outdoors, this test will be difficult to completely isolate from aerial signals, however in past experience the field produced by the Extra coil is almost entirely dielectric potential and never seems to radiate more than 1/2 of a mile (even at significant poewr levels).


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If you want to try something that might be dangerous:

Put a air-core solenoid around your coil, put at least 24v to it, whatever amps you have, say 10 or so. North pointing up.

DO NOT TURN THIS COIL OFF WHILE YOUR COIL IS ON. 
SLOWLY TURN IT DOWN TO OFF WITH A RHEOSTAT OR TURNS YOURS OFF FOR A BIT AND LET IT CHILL OUT.

Also, are your pulses unidirectional?  If so, Tesla's may have floated above ground.  I remember seeing that in an excellent reproduction once.

A double series gap will probably short your power supply, as it chokes the good stuff back behind the gaps.  Tesla did this initially, if you recall. (I did this twice, flames once...)
   

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Interesting idea Grumpy.   'Bouncing' the monopolar field off a larger static DC field? ???
Not quite set up for that this week but I can do it when I get back.

Quote
Also, are your pulses unidirectional?  If so, Tesla's may have floated above ground.  I remember seeing that in an excellent reproduction once.
CW, normal continuous waves.


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https://www.overunityresearch.com/index.php?topic=2704.msg43654#msg43654

An electrostatic transducer should work quite well when powered with a monopolar Extra coil.

We're still slaying telluric demons at Eric Dollard's shop and may not get much this week.  Lot of little things that add up.
 * Transceiver is 100w but limits itself to 50w under battery power (so 50w is the peak here)
 * Coil drive impedances are higher than expected (30-50 ohm, ideal is 10 or less)
 * One of the coils has a breakout problem at 50w, so we're forced to drop power even further for that one.
 * Receive station has a good ground but unknown impedance; may need better matching to receive.

Still waiting for final reception report but doesn't look great.  Eric thinks we just need more power, like 1kw+ to start getting reliable results.  Max ground currents measured with RF thermocouple ammeter is ~2.15 amps

Thankfully I have lots of experience gained from this little 'apprenticeship' to get my system up and running when I get home, and a very long write-up+how-to for others looking to get onboard :P


One thing we did manage to do though is a quick demo with a pair of coils concatenated to match an AM radio station 250 miles away.  Worked like a champ with the ground despite no conventional antenna :P


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Just got back from Eric Dollard's shop Saturday, spent a week helping him set up a telluric communication station there, and got my own "telluric apprenticeship" learning a lot in the process (especially regarding impedance matching and accurate telluric power measurements).

I plan on doing some formal write-ups and instructional pages/videos so others can replicate, but first acts are trying to replicate the exact setup here in the shop with what I've learned.

One thing Eric was insistent at every stage was minimizing impedance to ground.  To the point that the final tests were performed outside, directly atop a pair of 10,000+ gallon tanks with a ground impedance of approx an ohm.  And he was right.  Just removing few feet of bulk copper strap was enough to cause significant improvements in the 160m amateur radio band.

Based on what I'm seeing between the two sites and a quick test by the ocean today, it seems that ground plane surface area is FAR more important than simple resistivity.

My ground rod bored to the water table has a DC resistance of only 2.2 ohms to electrical ground, but presents as a whopping 70 ohm impedance when tested at 1.8mc!
The exact same setup (same transmitter, matching transformers, frequency, and coil) at Dollard's shop showed a combined system impedance of 13 ohms.

From a theoretical perspective, this makes perfect sense if we view the station as one plate of a capacitor to the Earth.  The surface area to the dielectric largely dictates its performance+efficiency.  It also explains why Wardenclyffe had such an amazingly deep and intricate ground system.


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I also did a few short videos from "Camp Dollard" :P, mostly for documentation purposes: O0
Part 1: https://www.bitchute.com/video/5yLTeokkMhGu/
Part 2: https://www.bitchute.com/video/bbGO367dwwf6/
Part 3 (debrief): https://www.bitchute.com/video/Wa1ncPrqn7Iw/

TL/DR we got some good AM radio reception @ 250 miles with Tesla Coils & ground, no conventional antenna, but 50 watts @ 12.5 ohms wasn't enough to punch the 100+ miles to the other site.  Possibly @ 1kw but unfortunately we just weren't set up for it.  We also need to check the Rx site to see how well the ground impedance is matched there @ 1.86mc.


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In the following video: https://www.youtube.com/watch?v=YIiPWthwBYE&t=6s
what makes them say that this is a "Successful Telluric Earth Transmission"?

Aaron isn't really an engineer so his video descriptions don't always accurately reflect the details of the experiments. C.C

That experiment was a rough test documenting some manner of exotic electrostatic reflection / telluric transmission through a remnant gas-lighting system running through the town to a well-equipped car tuned to the 160m band.

What was interesting about that test was that the response via overland radio more-or-less followed the gas lighting network.    The exact details are fuzzy but IIRC it was under 1/2 mile in one direction (where the lighting system ended) and many miles in the other direction.

The interior of the shop is entirely metal so it makes a fairly effective faraday cage (technically electrostatic screen).  Also remember that a Faraday cage can also become a radiator in the right conditions. ^-^

I was there during that test BTW.  It was damn cold out there! ;D



The "Steves" in the video did their own tests some time later that were more interesting IMO.
* First station was indoors, very intense ground but no external antenna.  Just a 160m Extra coil wound on a big polyethylene barrel.
* Second station was outdoors, with no antenna.  One short lead going to a deep wellshaft ground and the other going to a ground rod spliced into a deep tree root network.

They made contact on 160m band several times about 150 miles away under 80 watts over a few months.  Fairly poorly built and documented but the results were interesting enough to mention.  They also reported issues with different modes; apparently sideband and AM were impossible, that contact could only be made on CW.



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(Answering in this thread to try and stay on-topic)

My question was specifically about the facts of the Transatlantic Telluric Communication Experiment, including who, where, and what time of day...

Tesla (of course), 1900's on 50-80kc.
Intercontinental, as the measured 1/4 wave frequency corresponds to the Earth's circumference in longitudinal mode.

Ernst Alexanderson, 1910's-30's on multiple bands.
Patents specify system impedance below 10 ohms which all but necessitates a telluric component, and patents directly suggest it.

Eric Dollard, 1980's and 90's on the 40,80,160m bands.
350+ miles QSL at 599+, likely more.

Dr Adrian Marsh, 2019-2022 on 160m band.
Tests performed at multiple distances up to 110 miles.

Bruce Gavin (2019? to present?)
Unknown details (have not been in contact), but his ground is impeccable, and coil construction immaculate, which suggests high-level understanding of operation and likely some decent antennaless QSL's.

Steve Mcgreevey, spring+summer 2022 on 160m
150 miles+ between Steve Young.

Griffin Brock + Hakasays (Summer 2022) on 40-80m band.
Spotty reception at 130 miles with 60-100 watts.  Tx was a matched Tesla Coil into a pair of buried steel barrels, Rx was a ground strap tossed into the ocean.  Skywave and ground-reflection could not be completely ruled-out.


Also, since every grounded AM radio station is producing longitudinal telluric waves in addition to transverse AM transmissions, with the appropriate electrostatic shielding this technique might be used to detect and quantify the transverse+telluric components.


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Nothing about these experiences makes them any different from an ordinary radio transmission. Identical connections are made every day by radio amateurs around the earth.

F6, did you actually research into any of the names or experiments I listed, or are you still arguing from a position of ignorance?
You already admitted you knew nothing of Tesla's work at Colorado Springs; I suspect you didn't lift a finger here either.  C.C

Quote from: F6FLT
When I see a large tesla coil, I see a vertical spiral conductor with a large variable current flowing through it due to resonance, so I see a conventional tuned antenna, radiating a conventional vertically polarised electromagnetic wave.

I've asked you experiment by building a rudimentary LMD network analogue to get an understanding on the different properties and velocities involved in transverse vs longitudinal transmission lines as Eric Dollard did in the 80's.   https://www.youtube.com/watch?v=bNFpJVpm9Cs
If you've ever used a Vector Network Analyzer on a Tesla Coil, you would see that every coil wound as Tesla did displays Transverse resonance as well as Longitudinal resonance.

Dr Adrian Marsh at AMInnovations spent years studying and explaining this, and is one of the names listed above that you likely ignored:  https://www.am-innovations.com/category/equipment/equipment-network-analyser/





F6FLT, if you're serious about this, build a simple Transverse and a Longitudinal network and tell me the resonant frequency ratio between them.  Use the same number and value components for the whole network. (see reference below)
Until you understand the different properties of transverse and longitudinal networks you will never understand the principles involved in telluric communication.  If you're poor you can use an online circuit simulator and it should give you similar results (use a low impedance drive for transverse network, high-impedance drive for the longitudinal network).

  Hint: it is a geometric ratio, and it will approximate the same ratio regardless of what component values you choose for L and C. ;)
« Last Edit: 2022-08-31, 16:02:03 by Hakasays »


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Back to topic. 8)

Ground Resistance vs Impedance Experiments.

The main issue recently has been achieving a low-impedance ground, so that the 'standing wave' cavity is formed between the top of the Tesla transformer and Earth, rather than being formed between the top and bottom of the Tesla transformer.

When an impedance-matching transformer is used to drive an Extra coil, the system impedance of the setup has three components:
 * Drive impedance of the Tesla Extra coil.
 * Impedance of the matching transformer.
 * Impedance of the ground.

All of these three factors are related to each-other, and it seems that one poor-quality component will hurt performance on the others.
For example, if the ground has a very low impedance (2 ohm) but the coil has a high drive impedance (50 ohm), the coil will drag the system impedance up to some number between the two (perhaps 25 ohms).



Experimental setup

Transceiver: Icom 100w HF transceiver
Frequency: 160m band, approx 1.86mc for all.
Coil: 160m extra coil with adjustable mast.  Measured drive impedance with VNA ~35 ohms @ 1.86mc.  ~9.5in height + diameter, ~150ft #20 awg wire,  Magnification factor ~100.
Primary matching network: MFJ-969 Antenna tuner.
Matching transformer:  varies; best match recorded for each setup.
Ground current measurement: 0-5 amp RF Ammeter (thermocouple type).


Test #1: EPD Labs Indoors.
10ft ground lead attached to two 10,000+ gallon underground tanks.  Measured DC resistance less than 1 ohm to electrical ground.

Result: Peak ground current 1.8 amperes @ 50 watts input.
   50w / 1.8a = 27.7 volts
   27.7v / 1.8a = 15.43 ohms total system impedance.


Test #2: EPD Labs Outdoors.
Coil directly atop 10,000gal underground tank, 3ft of multiple low-inductance leads to the system.

Result: ground current 2.1 amperes @ 50 watts input.
   50w / 2.1a = 23.8 volts
   23.8v / 2.1a = 11.33 ohms total system impedance.


Test #3: Hakasays Shop Indoors good ground.
Coil directly atop a 28ft 1" diamete galvanized steel pipe, 14ft beneath water table.  Measured DC resistance 2.2 ohms to nearby electrical ground.

Result: ground current 1.3 amperes @ 100 watts input.
   100w / 1.3a = 77 volts
   77v  / 1.3a = 59.17 ohms total system impedance.


Test #4: Hakasays Shop Indoors poor ground.
Coil attached via 6ft of 1in copper strap to 8ft copper ground rod, 7.5ft driven into dense clay soil.  Measured DC resistance ~50 ohms to nearby electrical ground.

Result: ground current 1.25 amperes @ 100 watts input.
   100w / 1.25a = 80 volts
   80v  / 1.25a = 64 ohms total system impedance.


Test #5: Hakasays Outdoor ocean strap ground.
25ft ground strap tossed directly into the ocean.

Result: ground current 1.2a @ 50 watts input.
   50w   / 1.2a = 41.7 volts
   41.7v / 1.2a = 34.72 ohms total system impedance.


Test #6: Hakasays Outdoor ocean plate ground.
25ft ground strap tossed directly into ocean, also attached to aluminum sheet, approx 2sqft submerged.

Result: ground current 1.26 amperes @ 50 watts input.
   50w   / 1.26a = 39.7 volts
   39.7v / 1.26a = 31.49 ohms total system impedance.



Tentative conclusions: Ground electrode surface area appears to play a massive role in achieving a low-impedance ground, at least at these frequencies.
This is most evident by the near-identical results received with the ~2 ohm pipe ground and the ~50 ohm pipe ground.


(Note: photos reflect the setup conditions and not necessarily the exact coil under test.  All tests were performed with the same Tesla Extra coil)


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@Hackasays

You are precise in the descriptions, but I do not see any clear logic to rule out the very likely generation of EM waves and the fact that they are the only ones received.

Transverse and longitudinal networks exist in any bulk transmission media.  That's one of the points I am trying to emphasize.

Drop a bowling ball into a calm lake and you will generate two waves.  One will be on a transverse wave that travels along the surface and ripples outward.  The other will be a longitudinal wave that is undetectable on the surface.  Both waves will have very different properties.


As you can see, we're still narrowing-down the transmission and loss tangent characteristics of telluric longitudinal waves through the Earth.  Most of our work has been with continuous waves in the 1.9mc region which will likely have different cavity properties to impulse waves generated by Tesla in the sub-100kc region.

Quote from: F6FLT
You ask me to use a VNA, but a VNA says nothing about the transverse or longitudinal character of a line.

I asked you to build a transverse and parallel transmission line, either in real life or in a circuit simulator, because it more elegantly highlights the two distinct transmission modes across space.   I still await your results.



I understand that not everyone can afford the ~$500 vector network analyzer offered by sdr-kits.net and that it takes a lot of tinkering to learn how to 'read the tea leaves' to understand the data it generates. ???  It took me months and I've only scratched the surface.

VNA's are great though because it makes it SO much easier to tune complex arrangements like 3-coil Tesla Magnifying Transformers and. ;D
Adrian is the expert in the VNA front, and I've received much assistance and insight from his work: https://www.am-innovations.com/high-efficiency-transference-of-electric-power/


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**Removed F6 comments that bordered on trolling**
« Last Edit: 2022-09-02, 23:38:52 by Hakasays »


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Ahhh I realize that we have met before Hakasays, I now remember you said you were on this forum although I thought under a different name..wouldn't be the first time I've gotten my wires crossed though. We met at the energy conference year before last. I was working in Canada at the time and we both spent some time working on the Colorado Springs setup there with Eric and Adrian.

Really enjoying your experiments here. I might be wrong but in order to satiate the trolls and transmit power I think the setup needs to be significantly bigger.
   

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Ahhh I realize that we have met before Hakasays, I was working in Canada at the time and we both spent some time working on the Colorado Springs setup there with Eric and Adrian.

I think I know you, Poly :)  You were one of the few with us working 'behind-the-scenes' with the Colorado Springs TMT's while the rest were out listening to conference lectures >:-)   https://www.am-innovations.com/estc-2019-teslas-colorado-springs-experiment/

COVID finally let up enough that Adrian was able to come back to the 2022 conference to present; I finally got my well-needed crash course in handling the Vector Network Analyzer.
He's made some great progress these last few years, had some excellent discussions, and his preliminary results is somewhat where this transatlantic communication project spawned from.

One thing I've been trying to find lately is the bulk electrical properties of freshwater/saltwater, as knowing the inductance,capacitance,resistance,conductance at 50kc-2mc should allow us to directly model and predict the propagation characteristics in both modes.   Might just end up using the VNA and do the measurements myself :P

Adrian's been working with 3-coil systems, he is more focused on maximizing the cavity efficiency (his background is microwave so he tends to use that manner of language):  https://www.am-innovations.com/cylindrical-3coil-input-impedance-teslas-extra-coil/


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I think I know you, Poly :)  You were one of the few with us working 'behind-the-scenes' with the Colorado Springs TMT's while the rest were out listening to conference lectures >:-)   https://www.am-innovations.com/estc-2019-teslas-colorado-springs-experiment/

COVID finally let up enough that Adrian was able to come back to the 2022 conference to present; I finally got my well-needed crash course in handling the Vector Network Analyzer.
He's made some great progress these last few years, had some excellent discussions, and his preliminary results is somewhat where this transatlantic communication project spawned from.

One thing I've been trying to find lately is the bulk electrical properties of freshwater/saltwater, as knowing the inductance,capacitance,resistance,conductance at 50kc-2mc should allow us to directly model and predict the propagation characteristics in both modes.   Might just end up using the VNA and do the measurements myself :P

Adrian's been working with 3-coil systems, he is more focused on maximizing the cavity efficiency (his background is microwave so he tends to use that manner of language):  https://www.am-innovations.com/cylindrical-3coil-input-impedance-teslas-extra-coil/

Yep that's me. I went to that conference for one reason to meet Eric and do some work with him after quite a number of years corresponding online.

I remember being blown away but how easy the VNA made analysis, lucky that you got some more time with Adrian to learn from.

I am trying to remember an old book I read a while ago that might help with your question re impedance characteristics of fresh/sea water. I'll get back to you if I can locate it.

Thanks for posting Adrian's latest update, we stayed in touch for a little while after the conference but I have been in another world so to speak since getting back to Australia.

Why "bigger" ?
Do you have a calculation of the link budget in longitudinal waves, with the power to be emitted and their expected level in reception?

F6FLT, you clearly are an experienced radio operator. So I ask you, indeed, why bigger? What affect does size have on our waveforms? How does this waveform.interact with the medium? What is it exactly that is trying to be achieved here? A more fruitful discussion could occur here if there was more open mindedness to the concepts rather than dismissal without basic groundwork of experimentation and subsequent discussion.
   

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Please use side-threads for off-topic rants.



An article related to resistance v impedance results encountered last week: https://www.overunityresearch.com/index.php?topic=4320.msg100445#msg100445

Ground Resistance or Impedance?: https://www.nemasurge.org/wp-content/uploads/2015/01/grounding.pdf

Quote
The capacitance of the ground system dominates during the steep rising front of the impulse by providing a path to ground for these high frequency components. To assist this process, the capacitance of the ground system should be maximized. In practice this means that the surface area of contact made with the ground, must be as large as possible. The use of flat conductors instead of round, buried metal plates, meshes and ground enhancing materials (which effectively increase the surface contact of driven rods) are all ways of increasing the capacitance of the ground system's coupling to true earth.

Quote
The inductance of the ground system dominates during the rapid change of current with time as the current is injected into the earth. The voltage developed due to the inductive term is given by L di/dt. This may become dangerously large, creating the risk of a flash over, if attention is not paid to ensuring that inductance is minimized in the system. Sharp bends in down conductors and bonding connections should be avoided and the use of flat conductors, instead of radial ones, encouraged.

Quote
Finally, the resistance of the contact to the earth medium is particularly important during the decaying "tail" of the surge as this is where the large energy content (Joules) of the impulse resides. A low resistance contact ensures the safe dissipation of this excess energy into the ground. In practice this can be achieved by using longer driven rods, multiple rods, or by encasing the rods with conductive ground enhancing materials.

Quote
In summary - an effective ground system should exhibit a low impedance, rather than simply a low resistance, thereby ensuring it maximizes the dissipation of both the high and low frequency components characteristic of surges and fault transients.


In essence, not only must inductance+resistance be minimized, but capacitance must also be maximized in order to maximize longitudinal transient coupling to ground.

This lesson was well-learned in previous week's experiments, as the 2.2 ohm ground resistance exhibited a whopping 60 ohms impedance at only 1.8 megacycles! :o

Of course this probably means I need to bury a few steel barrels or sheets of stainless steel sheet to improve dielectric coupling and by extension resulting performance. C.C


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"Why bigger", I asked you this question. Only you suggest a bigger size, not me.

Everyone understands that the bigger the setup, the bigger the power of the emitted wave. I hope it is not by this trivial truism that you think you can justify that it should be bigger. And the size has nothing to do with the waveform you are talking about now, especially with Tesla coils, therefore resonant, therefore with a very narrow spectrum around the resonant frequency.

How much bigger? 1000 times? 10 times? What makes you think that the actual size would not be sufficient? And by how much?

When I make a radio link on 144 MHz, I know the power I need in relation to the antenna and the distance.
Without past link experience, and without a link budget, saying that we should take a bigger setup has no justification, and that's probably why we don't see you answer. You obviously don't know any technical reason about the size of the setup needed for the link.

A "more fruitful discussion" will be achieved not by accusing others of mindedness, but by respecting the other person. The principle is to give technical reasons for your proposals, not to say anything and refuse to justify yourself afterwards, and when you have done so, to admit that you spoke lightly, the mistake is human.

Sure I'll be open with you as to my reasoning. I mean no disrespect. Hakasays is presenting us with his research and experimental results, dismissing it out of hand assuming he knows nothing of what he's doing is not exactly disrespectful in my eyes.

Why bigger? What are we trying to achieve? If we are talking actual power transmission then what we are trying to achieve is a state of resonance within the Earth itself. Why bigger? What does bigger do to our waveform? It changes the frequency. What sort of frequencies was Tesla using in Colorado Springs?
   

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If you don't know where your longitudinal wave will pass, answering this question for all cases will give a huge range of orders of magnitude depending on the location, the depth, even often unknown especially when the path is deep in the ground, and the answer will be of no use.

https://www.falstad.com/circuit/
Select 'File: Open File' and open the attached .txt

Simulation attached to help explain why varying conditions may not be as critical as you think.  Capacitance can differ fairly broadly along a longitudinal transmission line and still not affect performance.

In attached sim, the dielectric loss tangent (conductance) would the primary loss factor.


A key question at the moment is whether Nikola Tesla was operating in the 50-100kc region because of these loss factors or due to technological limitations.   Determining the loss tangents at MF/HF frequencies should answer that question.


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"An overly-skeptical scientist might hastily conclude by scooping-up and analyzing a thousand buckets of seawater that the ocean has no fish in it."
   

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Telluric currents are not just on the surface of the earth.
Where is the longitudinal wave supposed to go?

F6, I'm glad you're actually asking technical questions now :D

It really depends what dictates the boundaries of the transmission line.

In 'normal' radio, the cavity would exist between the impedance boundaries of the Earth's crust and ionosphere.
Tellurically, it would appear to exist between the crust and upper-mantle (the same cavity that conducts surface seismic waves).

But since we need large electrostatic field gradients to create these impulses, we are also liable to create transverse waves in the air as a side-product, with the Tesla transformer acting as an EH antenna.  So that would have to be quantified and/or mitigated.

It's also entirely possible that the surface-ionosphere cavity and the crust-mantle cavity are both required for operation, as historical experiments did not have the capacity to isolate the two.

It's even possible that parametric boundary conditions like Zenneck waves are even at-play.  It's difficult to say at this point.



That's why I think it will be highly advantageous to analyze telluric samples with the VNA so we can start forming transmission line models, to be able to accurately predict+measure our experiments as we perform them (and give the math geeks something to play with :P).


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"An overly-skeptical scientist might hastily conclude by scooping-up and analyzing a thousand buckets of seawater that the ocean has no fish in it."
   
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