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#55 Data Visualization

Posted by geoalg on 21 July 2013 - 01:16 AM

Bewley lists a versatile function for the study of experimental wave forms on page 23 of "Traveling Waves on Transmission Systems."


[LaTeX Error: One or more directories do not exist]


where, in general, 'E', 'a' and 'b' are complex quantities.


The versatility of this function comes from the fact that the parameters can be modified to generate many functions such as infinite rectangular, ramps, impulses, sustained sinusoids, decaying sinusoids, and so on.


In Gnuplot, complex numbers of the form 'x1+ jx2' are represented with the following structure: {x1,x2}, 'x1' being the real quantity, and 'x2' the complex.


Here's a 2d plot of a particular damped sinusoid, with paramaters E=0.5j, a=0.1-10j, b=0.1+10j:

gnuplot> plot {0,0.5}*(exp(-{0.1,-10}*x)-exp(-{0.1,10}*x))


Here's a surface plot of the same function using splot :

gnuplot> splot {0,0.5}*(exp(-{0.1,-10}*x)-exp(-{0.1,10}*x))




With some parameter tweaks we get the impulse response:

gnuplot> plot {1,0}*(exp(-{0.5,0}*x)-exp(-{2,0}*x));






gnuplot> plot {0,0.5}*(exp(-{0.0,-10}*x)-exp(-{0,10}*x));



Convex rise:

gnuplot> set xrange [0.0:100]
gnuplot> plot {1,0.0}*(exp(-{0.0,0}*x)-exp(-{0.05,0}*x));



Exponential Decay:



More complicated waveforms can be synthesized through time shifting and/or superposition:


Decaying sinusoidal time shifted by five units with a Rectangular Pulse



Decaying sinusoidal combinded with a concave rising path


It's also possible to use the windowing property of the time shifted rectangular wave combined with another waveform (an inverted pulse for instance) to simulate reflected waves on a  transmission system.

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#176 Transmission Is Through Earth - Experimental Proof

Posted by dR-Green on 29 July 2013 - 03:26 AM

I also posted this on EF.


Experimental proof that the energy is transmitted through the earth by means of simply having multiple earth points set at various distances from the transmitter earth terminal and connecting to each one to receive. Simple.



20-22mm diameter copper pipes are used for receiver earth terminals. Details will follow. The transmitter has an earth rod of unknown length with 20cm or so and 37cm lengths of copper pipe in parallel, but the length of the ones connected to the transmitter are irrelevant in this experiment.


Distance from transmitter earth terminal (metres) : Pipe length (metres)

0.13 : 0.3
0.37 : 0.3
0.72 : 0.3
0.97 : 0.3
1.47 : 0.3
1.98 : 0.65 (doesn't count due to extra pipe length therefore better reception)

Also not shown in the video (but shown in diagram) are the two dirty earth rods which were put into the ground at a random distance for test purposes, both connected in parallel for receiving. Transmission distance in that case is 3.46 metres.

Transmitting and receiving coils are approx 10.3 metres apart (with stone wall blocking line of sight).


Power input:


F = 3670 kc
L = 0.66µH approx
Primary impedance (2Pi*F*L) approx = 15 ohms


Primary voltage = +/-0.7V = 1.4V p-p

I = 46.6mA

Peak Power = 32.6mW

RMS Power = 23mW


Test tone = C5 = 523.251 cycles/sec



Scope probe locations:




Waveform A (left) is the receiver primary voltage, Waveform B (right) is the audio signal.

Transmission distance = 0.13 metres




Transmission distance = 0.37 metres




Transmission distance = 0.72 metres




Transmission distance = 0.97 metres




Transmission distance = 1.47 metres




Transmission distance = 1.98 metres (doesn't count)




Transmission distance = 3.46 metres (not in video)





Many effects observed confirm that a bucket of soil accurately simulates a Telluric transmission situation, within obvious reason. Receiver is seen to respond even when standing on the ground around the transmitter earth terminal when holding a wire leading to the receiver in hand (and touching metal), and transmission will equally pass through human body when holding the wire to receiver in one hand and touching the transmitter earth terminal with the other hand. Laying the wire leading to the receiver on the ground around transmitter earth terminal also allows for reception of signal. This was to be filmed but the rains came again and this time the receiver was not sheltered so I was forced to abort.

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#141 Steinmetz and Longitudinal Waves

Posted by Raui on 28 July 2013 - 09:47 AM

My first language is german. My technical vocabulary isn't great but I can figure most of it out.


Awesome. I had just finished OCRing them and was about to fix up some errors and try a google translate but if you speak german you'd be able to do a better job than google translate. I bet any words that you don't know we could probably work out especially with the aid of a translation software.


Nice job Router! I don't know how the devil you managed to find that paper, but to say the least I'm impressed!


At first I thought you found a different paper, but after looking through the archive you uploaded the contents appears to follow with the descriptions in the abstract that I posted earlier! Though I'm confused as to why the abstract changed the name of Hund’s article?

gf9q.pngClick here for original .pdf

This abstract corroborates with the dates of the one I gave prior and the article's name you managed to find. Now I want to find Kennelly's paper that Hund cites and do some thorough reading. I think there are some gems waiting to be found in all these papers.


At any rate the contents seem to be pure gold regarding Eric's work, as Hund goes over the archetype electrical waves and even covers negative resistance. I'm curious if Eric ever came across Hund's paper...

Just a bit of search engine craftiness and a dash of luck :) I actually found the book first, well at least the name of the book, which I thought might be relevant because of the reference to symbolic math which is what Steinmetz' math is otherwise I would have been less sure than I was. Found it on a library page which allows you to look at any of the issues sorted by year. This is the site incase you're wondering: http://ezb.uni-regensburg.de/?2699370


I think you'll find that the Kennelly paper Hund is referring to is 'Impedance, Angular Velocities and Frequencies of Oscillating Currents' which is in Proceedings of the Institute of Radio Engineers dated 1916 from pags 47-78 which seems to match the reference in Hund's paper pretty well.


Attached File  Impedance, Angular Velocities & Frequencies of Oscillating Currents.pdf   2.61MB   9 downloads

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#641 Home Grown... Electronics Labs

Posted by G4ΓΓ3ττ on 07 December 2013 - 02:58 AM

As a quick update, I just acquired some more test equipment glom! Picked up four Keithley 427 current amplifiers, a 400vpp 4-channel amplifier and a Keithely 230 voltage source.


On a low point I thought I "fixed" my Keithley 220 current source but found new problems! When calibrating, it appears to work fine but when hooked up to a load the source voltage doesn't change when adjusted, arg! It stays locked in at 1v for the v_limit. The original issue was a hairline fracture on the second conductor of the triaxial bulkhead connector leading to the back of the unit. I think the V_source/limit issue is probably op-amp related, so it should be quick to repair once I get the motivation to disassemble it again.


I feel like I'm building a wall of equipment on my desk haha. The funny thing is I'm still not finished collecting gear, as I still want some hard to get items like a Tektronix curve tracer, an HP spectrum analyzer, a better oscilloscope and a decent spectrophotometer. The test equipment game never ends...

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#524 wireless power transfer

Posted by Beebrox on 29 September 2013 - 03:08 PM

Hi all,


i am new poster here, though i've been registered since beginning of the existence of this forum.


Firstly, congrats to everybody to put together such a great forum. I wish i have spent more time here, but hopefully i will in the future. I really like the latex and other posibilites here, but what i specially like about it is that it kind of selection of people from energetic forum based on skills.



Wireless power transfer.


While i am sure, it was discused all along by various people around the globe, prototypes were made as proof as concepts, here is a document i haven't seen in any of the sites and discussions, but it was published as summary of the field on opensource science site www.intechopen.com


Wireless power transfer has different options that are described in this scienfitic literature below.  Have fun and feel free to comment, discuss and make some practice of it, if desired.



Preface IX

Chapter 1 The Phenomenon of Wireless Energy Transfer:
Experiments and Philosophy 1

Chapter 2 Analysis of Wireless Power Transfer by Coupled
Mode Theory (CMT) and Practical Considerations
to Increase Power Transfer Efficiency 19

Chapter 3 Magnetically Coupled Resonance Wireless Power
Transfer (MR-WPT) with Multiple Self-Resonators 51

Chapter 4 Network Methods for Analysis and Design
of Resonant Wireless Power Transfer Systems 65

Chapter 5 Performance Analysis of Magnetic Resonant
System Based on Electrical Circuit Theory 95

Chapter 6 Equivalent Circuit and Calculation of Its Parameters of
Magnetic-Coupled-Resonant Wireless Power Transfer 117

Chapter 7 Compact and Tunable Transmitter and
Receiver for Magnetic Resonance Power
Transmission to Mobile Objects 133

Chapter 8 Realizing Efficient Wireless Power Transfer in the
Near-Field Region Using Electrically Small Antennas 151

Chapter 9 A Fully Analytic Treatment of Resonant
Inductive Coupling in the Far Field 173

Chapter 10 Enhanced Coupling Structures for Wireless Power
Transfer Using the Circuit Approach and the
Effective Medium Constants (Metamaterials) 191

Chapter 11 Maximizing Efficiency of Electromagnetic
Resonance Wireless Power Transmission
Systems with Adaptive Circuits 207

Chapter 12 AC Processing Controllers for IPT Systems 227

Chapter 13 A High Frequency AC-AC Converter for
Inductive Power Transfer (IPT) Applications 253

download here:




Regards, Beebrox

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#406 Home Grown... Electronics Labs

Posted by dR-Green on 18 August 2013 - 01:33 AM

Nice setup Garrett, there's a nice bit of equipment there.


I currently don't have a lab as much as a pile of junk. Up until recently everything has been done in my bedroom, my father recently retired from being an electronics service engineer so I've acquired all his components, parts he took out of machines, meters etc. Remaining on the desk is a Fluke 96B ScopeMeter, not in view is an old Philips analogue scope, 2x Universal AVO Meter Mk2, some other Model 500 analogue multimeter, 3x Uni-T digital multimeters that were on 50% sale, and a broken AVO All Wave Oscillator. As well as a DC bench power supply and other DIY power supplies. Also in view is a very broken KORG Polysix.




The shed is currently being converted into a lab, but the top part will house a drum kit and whatever other audio related things will fit. One of the CRT monitors is not working and will be stripped for parts.




More of the junk pile. This had been in the garage for years as my father acquired things but since he retired he wanted it out, so my bedroom and the shed had to make way for it otherwise it was going to the dump. I already lost a 12V 500 amp transformer and a cupboard full of hollow cathode lamps which got "donated" to a local university, which I was not happy to discover when I went to the cupboard to get one! Especially since they are going on ebay for around £200 each, and there was easily 20 of them. Fortunately I took two out before so they are the only two I have left. This pile consists of old car batteries, computers and related things, circuit boards, various parts from machines (generally spectrometers), and there are two more old Philips analogue scopes in there.




All that was stacked vertically to make some temporary space for experimenting in the opposite corner away from metallic/sensitive objects and what not. The plan is to put a bench in up against one of the walls but I haven't decided which one yet, probably up against the left in the picture. The water heater was also saved from the dump because it seems like it would make a good big capacitance.




Books that are relating to the subject.




Nikola Tesla - Colorado Springs Notes

Nikola Tesla - On His Work With AC

Thomas Commerford Martin - Inventions, Researches And Writings Of Nikola Tesla

Charles Steinmetz - Electric Discharges, Waves And Impulses

RCA - Radiotron Designer's Handbook 3rd Edition

ARRL - The Radio Amateur's Handbook 1961 & 1963

Ernst Guillemin - Communication Networks Vol 1 & 2

L Jacob - High Voltage Physics

Mullard - Transistor Audio And Radio Circuits 1st & 2nd Edition

Edward Hughes - Electrical Technology 4th Edition

E H Jones - Principles Of Radio & Electronics

J J Brophy - Basic Electronics For Scientists

K J Dean - Transistors Theory And Circuitry

M V Joyce & K K Clarke - Transistor Circuit Analysis

Siemens - Design Examples Of Semiconductor Circuits Edition 1974

Viktor Schauberger - The Water Wizard

Viktor Schauberger - Nature As Teacher

Viktor Schauberger - The Fertile Earth

Viktor Schauberger - The Energy Evolution

Callum Coats - Living Energies: Viktor Schauberger's Brilliant Work With Natural Energy Explained

Walter Russell - The Secret Of Light

Franz Bardon - Initiation Into Hermetics

Manly P Hall - The Secret Teachings Of All Ages

Manly P Hall - Lectures On Ancient Philosophy

Michael S Schneider - A Beginner's Guide To Constructing The Universe - The Mathematical Archetypes Of Nature, Art, And Science

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#40 Data Visualization

Posted by geoalg on 19 July 2013 - 05:51 PM

GNUPLOT is a useful tool for producing 2d and 3d plots for your experimental data.




Documentation: http://gnuplot.sourc...umentation.html

Tutorial: http://people.duke.e...in/gnuplot.html


If you are using Debian/Ubuntu, make sure you install the gnuplot-x11 package; otherwise plots appear to get swallowed by stdout.


GNUPLOT will generate various output formats, including post script which is a useful format for image imports into the LaTex document preparation system.


To give you an idea of the type of 2d output GNUPLOT can produce, here is a plot from recent data acquired from my 1000kcps coil system (output in png format).



Here's an example of a gnuplot session:

gnuplot> set grid
gnuplot> set ytics 0.1
gnuplot> set xtics 5
gnuplot> set xlabel 'Frequency (kcps)'
gnuplot> set ylabel 'Io_normalized (uA/uA) relative to 50uA peak'
gnuplot> set title 'Secondary System response to 1500pF experimental capacitor, C=C_max=1638 nF'
gnuplot> plot "measurements2.dat" using 1:3 title 'Normalized Field Intensity Vs. Frequency for Secondary System, Grounded' with linespoints

with the datafile (measurements2.dat) listing as follows:

# This file is called measurements2.dat
# Experimental Setup:
# Grounded secondary Response, c-1636nF, scale set to 50uA peak
# 6sn7 Triode Driver
#Fo (kcps)    Io (uA)    Io_norm(uA)
1119    5    0.1
1129    10    0.2
1134    15    0.3
1136    20    0.4
1139    25    0.5
1142    30    0.6
1142    35    0.7
1144    40    0.8
1147    45    0.9
1149    50    1
1151    45    0.9
1153    40    0.8
1153    35    0.7
1155    30    0.6
1157    25    0.5
1160    20    0.4
1163    15    0.3
1167    10    0.2
1178    5    0.1


Which produces the following output:


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#222 The Dollard "Four Quadrant Theory"

Posted by G4ΓΓ3ττ on 02 August 2013 - 03:03 AM

Jimm I never said I was going ban anyone, nor do I have the power to do so, just that things were getting off topic. Though I can see how my response could read differently. I should point out that no threats were made by myself, just a personal opinion, and to be honest I tend to agree with most of what you say--as hard as that may be to believe. I try to be as objective as a I can be. I don't subscribe to any one idea or person as being immutable or infallible. This forum isn't for inundating the weak of mind with sweet "Kool-Aid" dogma. The forum is intended to be a way to share projects, technical data and information with people who care to do the same. Personally, I'm always open to new ideas and people to research. I will admit that Eric has provided quite a few interesting ideas and references to read from, and that most here regard him highly, which can obviously cause conflict with those who don't see him in the same light. I can fully understand the frustration that is caused by that last fact--for both parties.


The point of my prior response was to remind everyone of the real intent of the new forum.


It would be nice if you stuck around; I think having someone with your experience in the field of radio would be helpful. I would like to hear what you have to say regarding the technical papers Router, Geo et al have dug up. Even your comments on Eric's four quadrant theory are welcome, at least by me. You do have to admit that your patronizing of Robert provoked him to quarrel with you. I'm not saying that either of you are wrong just that we can find a way to say what we want without causing a ruckus.

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#218 The Dollard "Four Quadrant Theory"

Posted by G4ΓΓ3ττ on 02 August 2013 - 12:41 AM



I don't want to cause a fuss, but let’s keep discussions productive. You can argue all you want as to why a theory or apparatus does or doesn't work but I don't want to see people arguing over Eric's character or personal situation on this forum. Those types of comments serve to do no good here and can be posted on the energetic forum or be sent via personal messages if you feel the need to vent. Further, I don't see how talk about homeless people is relevant here; the thread is about Dollard's four-quadrant electrical theory so let’s stick to it.


Remember we're all here because of like interests, while the specifics may differ we all want to share and learn new information. With that in mind, let’s keep things friendly and avoid pointless patronizing, expletives and "observations" outside of the scope of this forum.


Thanks for your understanding,



P.S. I'm going to move this thread to the Alternative Energy section, as it doesn't really pertain to radio.

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#21 Using basic latex in your posts

Posted by G4ΓΓ3ττ on 16 July 2013 - 06:55 PM

Excellent tutorial Router!
I thought I would complement your post with some external links to help people look up specific operators and symbols when posting math expressions in LaTeX:
Art of Problem Solving - LaTeX Guide
LaTeX Symbols
Good reference source to look up more advanced symbols such as a partial derivative [LaTeX Error: One or more directories do not exist], as well as simple ones like plus-minus [LaTeX Error: One or more directories do not exist] or minus-plus [LaTeX Error: One or more directories do not exist].


LaTeX Commands

Covers the basics of various mathematical commands like; exponents [LaTeX Error: One or more directories do not exist], fractions [LaTeX Error: One or more directories do not exist], radicals [LaTeX Error: One or more directories do not exist], logarithms [LaTeX Error: One or more directories do not exist], trig functions [LaTeX Error: One or more directories do not exist] (you use extra formatting to get big parentheses btw), and calculus [LaTeX Error: One or more directories do not exist]  or  [LaTeX Error: One or more directories do not exist].






Similar to the above references but covers some slightly different things like matrices [LaTeX Error: One or more directories do not exist] and variants of math commands.


Trinity College, Dublin - School of Mathematics


Getting Started with LaTeX


Covers all the basics of LaTeX, not just the math side, for those who want to learn more about how and where it's used.

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#162 Steinmetz and Longitudinal Waves

Posted by G4ΓΓ3ττ on 28 July 2013 - 09:56 PM

Hi guys,


I got Hund’s paper (compliments of Router's hard work) complied into a single .pdf. I took the liberty to remove other articles that were on the same page as Hund’s, since I found them distracting and did some other house cleaning. (However, I will upload both for people to download.) Also, I OCRed them with BlueBeam PDF Revu (although I didn't have the German language addon) and attempted to use Google Translate... At first attempt it seems hopeless to use Google to translate the paper, but I blame my OCR program as well... It’s practically unintelligible. Maybe someone else will have better luck? I’m most interested in reading Hund’s spiel on negative resistance. And now I'm off to finding some dynatron tubes...


August Hund - Bi-Symbolic Equations & Their Use in Electrical Engineering, 1920

August Hund - Bi-Symbolic Equations & Their Use in Electrical Engineering, 1920 (unedited)

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#137 Steinmetz and Longitudinal Waves

Posted by Raui on 28 July 2013 - 03:11 AM


I've managed to locate August Hund's paper, you can find anything if you dig in the right spots! :D As you expected it's in German but never fear, I think I have ways around such a language barrier.


Bi-symbolic Equations and their use in Electrical Engineering [GERMAN]


According to World-Cat there is a book with the same name by Hund. By the way for reference the name of the papers in German is "Bi-symbolische Gleichungen und deren Verwendung in der Elektrotechnik"

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#118 Steinmetz and Longitudinal Waves

Posted by Raui on 26 July 2013 - 01:48 AM

But, we already know that the pdf is in the IEEE archives, so who's going to help us get that paper? Someone needs to throw some water on Router, and short circuit his beauty sleep.


Beauty sleep short circuited..here you go gentlemen. It does certainly sound like a very interesting paper. Beats reading the news with my morning tea ;)

Attached Files

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#1160 A new Model for the electron charge probablity 'cloud'

Posted by G4ΓΓ3ττ on 18 April 2014 - 08:18 PM

Very cool topic!


Statistical probability of spatial distribution is a fascinating concept. In my (basic) chemistry classes the subject is treated as having an absolute position in space at all times (no accounting for quantum effects). However, more complicated chemical relationships like a helium-3/helium-4 heat pump, which operates by principles of the van der Waal's force, can't be explained by a discrete position in space. Probability of the electron's charge is needed to show that "neutral" atoms can have very slight charge imbalances, so as to create mechanical forces with other "neutral" and non-neutral atoms. Same applies to the Casmir force, now known as the "retarded van der Waal's force," the repulsive force at distances greater than 20nm. Its interesting that as distance increases the vector forces of the van der Waal's force change direction. Some say it's due to the change in phase as the EM forces move through atomic scales of space.


Plato's Allegory of the Cave comes to mind when thinking about the electron from the perspective of the macro world. Clearly, the electron has properties beyond anything we observe normally: it has no physical dimensions (similar to the photon, according to Neil deGrasse Tyson), yet it has a definite rest mass but no definite position in space when examined at atomic scales. Paradoxes of the macro world become the reality of the atomic.


You know, I wouldn't be surprised if electrons and photons were somehow interconnected in a higher order space, where one interchanges into the other and vice versa. The most boggling aspects of physics, to me at least, are the nuclear forces and neutral matter, like neutrons, as well as gravity and mass...

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#1144 Misnomer of "Positive" and "Negative" in Circuits

Posted by G4ΓΓ3ττ on 06 April 2014 - 05:17 AM

The Logic of 0V and the Confusion of + & -


After conversing with a friend today about batteries and circuits I became bothered by liberal use of "negative" and "positive" in labeling BOTH sides of a voltage source or terminals of a battery. While possibly being pedantic, I brought up the notion that positive and negative only exist to show direction in regard to some absolute or relative reference point, generally a "zero voltage" point called "common."


For example, if the "negative" terminal of a battery is connected to common, we only measure "positive" volts; if we reverse the battery's connection we measure "negative" volts. My gad sir! The illusion most people fall into is that we can have BOTH positive and negative terminals at the same time! Which would mean each battery terminal is somehow referenced to our zero-volts common. In reality, we have either "positive" or "negative" x volts at the free terminal with zero volts at the common connected terminal, but not both! The only condition that would allow BOTH is a split rail supply where we have TWO voltage sources connected in series with the COMMON at the center. In this case we have, say, +12V,0V,-12V. For single supplies you can have either -12v,0v or 12v,0v, but certainly not +12V,-12V with -12V as the "common," as that would be 24V!


To extend the concept further with electrostatics, an isolated conductor can be "charged" either positive or negative, but not simultaneously both. The difference in charge of the isolated conductor creates a potential difference with both neutral, oppositely charged conductors and same charged ones of less or more charge. That is, any difference in the quantity of charge creates a potential difference regardless of charges being positive or negative. For electrostatics, the reference of zero-volts becomes any neutral matter.


The ultimate irony is that older literature (70s and older) had the good sense to label circuits as I've described, but newer especially home-brew articles make a mess out of the idea of positive and negative with regards to voltage sources. To exacerbate this problem, battery manufacturers label the terminals as "+ -"! Use of anode and cathode could entirely eliminate this confusion with batteries as these denote the polarity without invoking misleading ideas in regards to voltage sources.


And now a moment of zen from Walk Hard: The Dewey Cox Story (a Jonny Cache parody) rehab scene:


Cox: "Ahhh I'm hot and cold at the same time!"

Nurse: "He needs more blankets AND he needs less blankets!"

Doctor: "I'm afraid your right."

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#10 Using basic latex in your posts

Posted by Raui on 15 July 2013 - 02:14 PM

I thought I'd post a quick and very basic latex tutorial for those unfamiliar with it. First of all LateX is a text rendering program which is awesome for rendering mathematical expressions. Obviously with the material on here we're going to need to show mathematical expressions.


First of all to start an equation we use the either of the following tags


Now for some examples. You will first see the rendered equation and then see the BB code responsible for generating it.


Fractions example;

[LaTeX Error: One or more directories do not exist]

[math]R=\frac {V}{I}[/math]

Subscript example

[LaTeX Error: One or more directories do not exist]


Powers example;

[LaTeX Error: One or more directories do not exist]

[latex]e^{ix}=\cos x + i\sin x[/latex]

Note that the '\' character in latex denotes that what follows until the next space is an identifier. This identifier works for most common math expressions and more importantly greek letters.


Symbols example;

[LaTeX Error: One or more directories do not exist]

[latex]\psi = \Psi + \phi + \Phi + \Pi + \pi[/latex]

Note that if we want the capital greek letter we start the identifier off with a capital eg \Psi instead of \psi


I will make a thread sometime tomorrow with a more comprehensive list of commands. While it might seem daunting at first it becomes second nature to you after a while. Just in case the post tomorrow doesn't get made in time for wanting to post an equation here is a good website which you can design the equation how you want and it'll show you the code you need to represent it in latex.


CodeCogs Equation Editor



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