Sorry about that, anyway here is a pic.
Top trace is input signal.

Thanks you for posting a screenshot of your scope readings, however to convince me of what you are saying you will need to do more than this.

I want to make a casual observation of your experiment:

You state that if "a signal is applied to a circuit that is non-capacitive and non-inductive", but as thingmaker3 correctly pointed out above: "How do we achieve zero capacitance and zero inductance in the real world?" Whether we consider your experimental set-up or think of this purely as a TM line thought exercise, your set up will have (parasitic) inductance and capacitance therefore cannot satisfy your one criterion above. Quoting appropriate sources:

For parasitic capacitance: Voltage applied between two conductors creates an electric field between those conductors. Your frame has the main TM line interleaved with the return path, therefore some form of parasitic capacitance will be present in the set-up.

For parasitic inductance: Current through any conductor develops a magnetic field of proportional magnitude. Energy is stored in this magnetic field, and this storage of energy results in an opposition to change in current. For your TM line the wire develops a magnetic field as it carries charging current for the parasitic capacitance between the wires.

Therefore, you are suggesting that your model is an ideal model with zero inductance and capacitance, I say this is impossible due to the very nature of physics. So to back up your claim can you prove that your set-up exhibited zero inductance and zero capacitance?

Dave

 

Putting any semantics aside, I can only suggest that you construct the experiment for yourself to confirm the results.
However, I might also suggest that you re-read the documentation, because the return wire is NOT interleaved with the main TM line.

As stated in the documentation, the purpose was to keep the capacitance and inductance to a minimum.

One of the earlier replies said there was nothing new about it's content. I stated in the document that the experiment was conducted at least 25 years ago and submitted to an electronics magazine. It is not my experiment, simply my version of it. If I have offended anyone by reiterating the obvious then I apologise.

The significant issue that the results seem to indicate, is that the velocity of light is not a limiting factor in the velocity of propagation of a signal in a conductor. By virtue of Kirchhoff's Laws and the results obtained, I believe it is a valid extrapolation to assert that IF capacitance and inductance were zero then the velocity of propagation would be infinite. Again, the purpose was to minimise capacitance and inductance in order to detect an absolute minimum delay, which should have been 1uS!!!

The results indicate that the delay in 300 Metres is much, much less than 1uS, and within the limits of my manufacturing ability and test equipment, I could not discern any delay.

I am certainly not trying to increase the speed of light, nor am I suggesting that this is an example of zero capacitance or zero inductance.

Until Einstein's theory becomes Einstein's Law I am entitled to question it's validity. I would never doubt Kirchhoff's Laws.
Finally, I maight simply ask a question - can information be transmitted faster than light?
I would be happy to hear from anyone who has conducted the experiment (or a similar one) for themselves.

 

One of the earlier replies said there was nothing new about it's content. I stated in the document that the experiment was conducted at least 25 years ago and submitted to an electronics magazine. It is not my experiment, simply my version of it. If I have offended anyone by reiterating the obvious then I apologise.

Could you provide the source, or at least the name of the magazine and edition, that you got your version of the experiment from? I am curious to read further into your arguement before I make any further comments. A Google and University library search produces nothing except a few papers on infinite velocity of propagation for thermal transfer (many of which are disregarding it, but thats another story).

Also I have re-read your document and I retract the comment regarding the interleaving of the TM line and the return path. However, from my understanding of your experimental set-up I still believe there to be discernible capacitance present.

Until Einstein's theory becomes Einstein's Law I am entitled to question it's validity.

And so you should, all of science is open to questioning, that is the beauty of it and hence why I am questioning your experiment and conclusions.

Finally, I maight simply ask a question - can information be transmitted faster than light?

Considering the concept of "Apparent faster than light" - No. But this once again is another topic.

I will continue to muse of this debate in the coming days, however the football is on tonight so it have to wait till tomorrow

Dave

 

It MAY have been either "Electronics Australia" or "ETI" (Electronics Today International). At the time they were generally the magazines I subscribed to.
Unfortunately as time goes by, the magazines have been lost to me but the memories linger on.

With respect to your insistance that there must be capacitance and inductance in the circuit, and thingmaker3's question "How do we achieve zero capacitance and zero inductance in the real world?" I am sorry thingmaker3, I thought it was a rhetorical question. The answer is: WE CAN'T.

Is there capacitance and inductance in the circuit? Of course there is.

Is it valid to extrapolate from known information to the ultimate (albeit unachievable)? Yes I think so.

Does the signal applied to the start of the 300 metres get to the resistor in LESS than 1uS? Yes.

I would be happy to assist, in any way I can, anyone who is thinking of conducting the experiment for themselves. By all means, build the thing, conduct your tests, improve on the design and manufacture, and draw your OWN conclusions. Don't just shoot the messenger.

 

I have a few more questions and queries before I formally set down my ideas and thoughts on your experiment:

1. Can you provide us with details of the measures you have taken to reduce both the capacitance and inductance present in the system? And details of the steps and quantitative results you have taken to verify that the inductance and capacitance in your system are negligible? Other than your say so, I am yet to be convinced the inductance or capacitance is negligible (zero), or even small.

2. In your diagram you have stated that your load is a 1MΩ, can you elaborate? Is it a single 1MΩ resistor, or is it a parallel block of resistors whose total resistance is equal to 1MΩ? Is(are) the resistor(s) wire-wound resistor or carbon resistors?

3. I am concerned that you are making the assumption that "The results indicate that the delay in 300 Metres is much, much less than 1uS" when you are using a scope with a bandwidth of 60MHz and sample rate of 1Gs/s. The bandwidth limitation of your scope makes any assumptions based on measuring the response to such a fast changing input signal to be invalid. From speaking to several Tomographic Measurement Engineers at work, they verify that this is insufficent to make any accurate measurements on the time scales you are stating. Can/have you performed the measurements using a scope with a more suitable bandwidth capability and better ADC sampling rate? Also can you provide a zoomed screen shot of the input and output, for example a screen range of less than 10uS?

Btw, it may seem that I am "shooting the messenger" however I'm only challenging your experiments and arguements. I mean nothing personal in anything it say, and fully respect your right to put you case forward on a public forum.

Dave

 

Hi,

Yes, at this point, questions like how long since your test equipment was calibrated become germaine.

And there is test equipment just made for this purpose - a Time Domain Reflectometer. Tektronix makes a line of them. I would have fewer problems with the results from a TDR. They even work nicely with unterminated transmission lines.

 

I'd have less problems with a calibrated nS counter, once all the cabling was tested and the delays were known.

 

I would like to offer the following in this debate. The magnetic fields in any two wires forming a loop in the frame tend to cancel out because current is flowing in opposite directions. So the total inductance of the length of wire will be reduced.

But throughout each frame capacity exists between any wire and its neighbour. Coupling exists between any given point on the wire and a point further down the wire. So there is an infinite number of such capacitive couplings throughout each frame and from frame to frame. The result is that, overall, considerable capacity exists between the ends of the wire. The equivalent circuit of the setup will probably be that of the input waveform being fed to the output (end of line) via a CR network.

I think the high value of terminating resistor may have a direct bearing on the results. Why such a high value, anyway? – there is no reason for it. If the claim put forward in the paper mentioned is valid, the value of the resistor should not matter.

It would be interesting to see the results of these two modifications:

• Fitting a Faraday Screen between each frame, with each screen bonded to ground at one point to reduce coupling between frames.
• Change the value of the terminating resistor to be the same as the source oscillator.

 

OK!
If you build the thing, you can answer all those questions for yourself.
If you don't want to build it because the results might be too contraversial or disturbing, then don't build it.
If you have access to better equipment, then I would love to see your experiment and your results.
If you conduct the experiment, then you can draw your OWN conclusions.
If you wish to draw your conclusions without conducting the experiment, then fine, let's hear them.
As for the 1M resistor, it doesn't matter! Use a 2K2 or 10K or 100K - whatever you have!
I have neither the time nor the resources to write a thesis on the experiment, I look forward to your analysis of YOUR experiment.

 

"Argumentum ad ignorantiam" is the logical fallacy of claiming something must be true if it is not proven false.

Which does Occam's Razor support - a scope needing calibration or an undiscovered flaw in Einstien's application of the Lorentz transformations?

 

OK!
If you build the thing, you can answer all those questions for yourself.
If you don't want to build it because the results might be too contraversial or disturbing, then don't build it.
If you have access to better equipment, then I would love to see your experiment and your results.
If you conduct the experiment, then you can draw your OWN conclusions.
If you wish to draw your conclusions without conducting the experiment, then fine, let's hear them.
As for the 1M resistor, it doesn't matter! Use a 2K2 or 10K or 100K - whatever you have!
I have neither the time nor the resources to write a thesis on the experiment, I look forward to your analysis of YOUR experiment.

I think you may have a misconception regarding this debate: YOU are the one who has proposed this experiment and drawn a set of conclusions from your version of the experiment, therefore the onus in on YOU to prove that what you are claiming is true/accurate/correct, it is not the duty of US to disprove your claims. If you are not prepared to convince us of your arguement, then how can you expect us to take the time to build this experiment ourselves - it is like me saying that I have a design for a craft that can travel faster than light, you would need convincing of its merit before you decided on putting the design to a test of your own. At this moment your experiment has many outstanding questions and issues which you have not provided answers for.

So I reiterate my early questions:

1. Can you provide us with details of the measures you have taken to reduce both the capacitance and inductance present in the system? And details of the steps and quantitative results you have taken to verify that the inductance and capacitance in your system are negligible? Other than your say so, I am yet to be convinced the inductance or capacitance is negligible (zero), or even small.

2. In your diagram you have stated that your load is a 1MΩ, can you elaborate? Is it a single 1MΩ resistor, or is it a parallel block of resistors whose total resistance is equal to 1MΩ? Is(are) the resistor(s) wire-wound resistor or carbon resistors?

3. I am concerned that you are making the assumption that "The results indicate that the delay in 300 Metres is much, much less than 1uS" when you are using a scope with a bandwidth of 60MHz and sample rate of 1Gs/s. The bandwidth limitation of your scope makes any assumptions based on measuring the response to such a fast changing input signal to be invalid. From speaking to several Tomographic Measurement Engineers at work, they verify that this is insufficent to make any accurate measurements on the time scales you are stating. Can/have you performed the measurements using a scope with a more suitable bandwidth capability and better ADC sampling rate? Also can you provide a zoomed screen shot of the input and output, for example a screen range of less than 10uS?

If you are not prepared to answer the questions and queries regarding your proposed experiment, then please say so and we can stop wasting our time and put this one to bed.

Dave

 

To Dave,
With respect to question #1: I just took the original author's design and constructed it. I accepted the concept as "pebe" pointed out, re the non-inductive winding. Did I measure or test the amounts of capacitance and inductance? No, I was more interested in the results. Did I accept that by keeping the conductor diameter as small as practicable, and increasing the distance between them would reduce the capacitance? Yes.

Re #2: It was just a 10% carbon, common garden variety. Nothing special.

Re #3: You and your Engineers assert that the equipment is inadequate, and this may or may not be the case. If it IS the case then what would be the point of providing a zoomed screen shot? You have already stated the equipment is NOT adequate.

I have never suggested that it was your DUTY to prove or disprove anything! That is a burden I would NEVER impose on anyone. By the way, who is US?
Nor have I stated that the experiment is PROOF of what I have said. I merely offer it as EVIDENCE.
I have twice built the experiment. The first time was simply out of curiosity.

To pebe,
I think that using a Faraday screen would increase the capacitance in the circuit. The 1M resistor value is not important, any reasonable value will do.

 

To Dave,

.......To pebe,
I think that using a Faraday screen would increase the capacitance in the circuit. The 1M resistor value is not important, any reasonable value will do.

A Faraday screen between each frame would certainly increase the capacity to ground, but it would eliminate the capacity - and hence the signal coupling - between frames. There is some inherent inductance in the wire so the setup must be a transmission line of sorts - though I wouldn't like to hazard a guess as to its characteristic impedance.

I suspect the leading edge of the received waveform is the differentiated signal caused by the CR coupling that I stated earlier, and the damped oscillation in the rest of the waveform is the result of the signal being reflected by the incorrectly terminated line. The value of the resistor will effect both.

 

Hi pebe,
Thank you for your suggestions and interest.
I think the main idea was to minimize capacitance to ground, but I accept your reasoning.
I also agree with your reasoning about the terminating resistor. Whether it was your suggestion, or me straining the old memory, I think the original was much less than 1M. Sorry, I just don't remember the value.

I might also add that the original was a 1 Metre x 1 Metre frame - very difficult to handle. Maybe by trying to make the framework more stable, I may have inadvertently affected the signal coupling.

Unfortunately at the moment much of my equipment is on loan to my daughter. When I get it back, I will play with the thing and if you are still interested, I will try to post the results.

 

Hi MaxL,
Yes, I would be most interested in seeing the esults.

 

Hi Guys,
Sorry it took so long to get back.
Here are the results with a 1K terminating resistor.
(I guess my memory failed me again.)

Unfortunately due to circumstances beyond my control, I will not be able to conduct any further experimentation on the equipment.

Best wishes for the future, I will try to log in from time to time.

Regards, MaxL

 

Hi,

Finally, I maight simply ask a question - can information be transmitted faster than light?

Well, someone hasn't been paying attention...
It's old news these days, but one of our gals here in DK slowed the speed of light substantially a number of years ago and since then, I believe, some americans have slowed it even further... So, with that in mind, the answer to your question must be yes.

(Oh yeah, she F'd up a whole lot of "rigid truth" and bashed Albert a bit as well - and we still haven't seen the last of the repercussions, only the sligt beginnings of them in fact).

 

Sorry to bring up such an old thread, but I found this interesting. It does make sense (from transmision line theory), That if you make a non inductive line (I.e make magnetic flux zero in the line=> make H zero in the line), the velocity of propigation (or phase velocity) will be infinite. This is because the phase velocity of a transmission line is:

1/sqrt(L*C).

now since L is zero on a non-inductive line, the phase velocity is infinite.

I am not saying that this is correct, but it just seems to be an interesting point. My one concern is, as inductance goes to zero, does the capaciance of the line blow up to a large number, keeping the phase velocity equal to or below the speed of light? Hopefully this helps explain what MIGHT be going on here.

I just found this article and the more interesting thing about it is the claim that the gravito-magnetic field is measureable....If anyone has tried this experiment (in a vaccum or someplace where there is no air coupling) please let me know.

Thanks

 

Sorry to bring up such an old thread, but I found this interesting. It does make sense (from transmision line theory), That if you make a non inductive line (I.e make magnetic flux zero in the line=> make H zero in the line), the velocity of propigation (or phase velocity) will be infinite. This is because the phase velocity of a transmission line is:

1/sqrt(L*C).

now since L is zero on a non-inductive line, the phase velocity is infinite.

I am not saying that this is correct, but it just seems to be an interesting point. My one concern is, as inductance goes to zero, does the capaciance of the line blow up to a large number, keeping the phase velocity equal to or below the speed of light? Hopefully this helps explain what MIGHT be going on here.

I just found this article and the more interesting thing about it is the claim that the gravito-magnetic field is measureable....If anyone has tried this experiment (in a vaccum or someplace where there is no air coupling) please let me know.

Thanks

I'm interested in how you are going to make a non-inductive line.

 

Well Inductance is associated with storing magnetic energy. To be exact,

L=flux linkage/current

the flux linkage is the magnetic flux multiplied by the number of turns in your line/unit length. the magnetic flux is B dot A. So if you make B zero in your line, the flux will be zero, making the flux linkage zero, giving you zero inductance. This is all fine and dandy, but back to the question:

For a solinoid B (inside) = u0*N*I.

Now if we make two solinoids that are intersecting, and apply an AC signal accross them one solinoid will have a magnetic field:

B1 = u0*N*I

and the other will have a magnetic field

B2 = -u0*N*I (because current is going the opposite direction)

So if we sum the field inside the transmission line (i.e. the two solinoids):

B = B1+B2 = 0 => L= 0.

Here is the catch. I was playing around with this problem and realized that altough the phase velocity of such a line is infinite, what can be sent over the line is a problem.

Also from basic transmission line theory, Z0 (the intrinsic impedance of the line) = sqrt(L/C).

This means that the impedance of the line is Zero. =>
the reflection coefficient is 1 => all power is always reflected from such a line. I do not know if this would effect data transmission, but this line is definately undesirable for power transmission applications. I'll look in to seeing how total reflection effects data transmission...

Sorry to blurb on and on, but I thought this was pretty cool and thought I'd share some insight.