#### Rodal

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##### Re: EM Drive Developments
« Reply #3320 on: 11/19/2014 01:40 AM »
Don't read to much into my fields graphic. It might be weak/strong field. But I'm sure that blue is strong e-field. I'll find out and of course tell all

Quote
Briefly, the -Zc dkbluered makes the color scale go from dark blue (negative) to white (zero) to dark red (positive),

The cavity was excited with  an Ez field, (electric field) so the colors are a measure of the electric field. I could excite with a magnetic field if that would be helpful.

There should  be an electric field and a magnetic field inside the cavity.
In some modes (TE) the electric field is rotational (transverse).  Then the magnetic field is axial. It is obtained as (1/omega) times the curl of the transverse electric field. Where omega is the angular frequency (2 Pi f ).

In other modes (TM) the magnetic field is rotational (transverse).  Then the electric field is axial. It is obtained as (c^2/omega) times the curl of the transverse magnetic field.

Higher modes have the fields in smaller domains, with nodes (zero field points) in between the domains.

Preferably, in a numerical solution, you should get both the electric and magnetic fields at once.

If you cannot get both field solutions at once, then by all means excite them separately (but of course keep exactly the same frequency and boundary conditions).

Also please show (in addition to the current perspective) the fields in a direction looking perpendicular to the big diameter, so that we can check that (for example in this case) the electric field is indeed rotational (transverse) and that it goes to zero along the cone's axis.
Or at an angle, as shown in the below pictures
« Last Edit: 11/19/2014 01:45 AM by Rodal »

#### JohnFornaro

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##### Re: EM Drive Developments
« Reply #3321 on: 11/19/2014 01:49 AM »
But it logically follows (to me) that for somebody  ... who thinks that the dielectric placement in the microwave cavity has an interaction with the Quantum Vacuum, that they ... would place the dielectric always in a consistent manner both in the Cannae and the truncated cone, and if they wouldn't I would expect them to write about it and explain why they would have placed it inconsistently.

That is a charitable expectation, to be sure.  It cannot be claimed, however, that the device will thrust in the preferred direction based on the testimony of the experimentors, and that also, the placement of the dielectric can be inconsistent without an explanation of its cause or effect on the experimental results.

Inertia is a property of matter.

Sciama might disagree.

Or did I just demonstrate my vast ignorance again?

Not sure about that probability, I mean, what do I know?  I'm actually a poker player.
Sometimes I just flat out don't get it.

#### IslandPlaya

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##### Re: EM Drive Developments
« Reply #3322 on: 11/19/2014 03:57 AM »
Did someone state inertia is a property of matter?
Man, you may be right, but stating it doesn't make it true!
What do you think the good people have been exploring?
Sheesh!

#### DIYFAN

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##### Re: EM Drive Developments
« Reply #3323 on: 11/19/2014 06:01 AM »
Upon closer inspection, it is suggested that only the plate having the larger diameter (R1) be made of metglas 2714A to obtain the amplified thrust in the indicated direction.

In his recent paper,
https://hal.archives-ouvertes.fr/hal-01074608/document
De Akino suggests using pulse modulated radar to produce high power microwaves during short time intervals (pulses).  Because of the pulsed nature, the overall power usage is relatively small.

Exploring this a bit further, I can imagine something like this Siemens built pulsed radar transmitter being used, which sells for about \$1800 on ebay:
http://www.lesman.com/unleashd/catalog/sensors/sensors_probelr.html

Here is the user manual:
http://www.lesman.com/unleashd/catalog/sensors/Siemens-SITRANS-ProbeLR/SIEMENS-sitrans-probe-lr-man-a5e32337711-001-aa-2013-12.pdf

It seems like it would be simple to slip the antenna of the transmitter through a simple round opening in the test article.  The pulses (i.e., measurements per minute) are adjustable from 0 to 99999 (pp. 55-56 of user manual).

One issue is that the frequency of this transmitter appears to be fixed at 6GHz, so it would not be possible to sweep the frequency to find resonance.  I suppose one could model and simulate the dimensions of the test article in advance (e.g., such as the interesting efforts being made by aero), determine its resonant frequency, and build the test article to fit the frequency.

It is also not clear to me what kind of power each of the pulses produces from this transmitter.  The input power is a maximum 30 V DC at 4 to 20 mA.  But since it is a pulsed microwave, this does not necessarily inform what the power would be for each pulse.

Thoughts?

#### JohnFornaro

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##### Re: EM Drive Developments
« Reply #3324 on: 11/19/2014 12:36 PM »
...It is also not clear to me what kind of power each of the pulses produces from this transmitter.  The input power is a maximum 30 V DC at 4 to 20 mA.  But since it is a pulsed microwave, this does not necessarily inform what the power would be for each pulse.

Thoughts?

Well, the propulsive efficiency of the "advertised" experimental devices is very low.  For some reason, I seem to be the only person to put this in English:  The devices aim to convert electrical energy into linear momentum.  Therefore it is reasonable to consider the energy input as the analog of propellant.  While propulsive efficiency itself could be improved with a demonstration of the effect, it would make sense to crank up the input power.

Other than the pesky theoretical details, the thought to be "positive" results continue, after a decade or so of experimentation under wildly varying theories of operation, can barely be discerned from the underlying noise.

There have been a handful of suggestions up thread to increase the input power so as to increase the expected thrust results.  You aren't gonna make the Kessler run in a handful of *cough* parsecs on 4 to 20 mA, and I'm thinking you aren't gonna get "positive" results with such a small power input.

But hey.  What do I know? I'm just a gadfly.
« Last Edit: 11/19/2014 12:40 PM by JohnFornaro »
Sometimes I just flat out don't get it.

#### Rodal

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##### Re: EM Drive Developments
« Reply #3325 on: 11/19/2014 01:58 PM »
...It is also not clear to me what kind of power each of the pulses produces from this transmitter.  The input power is a maximum 30 V DC at 4 to 20 mA.  But since it is a pulsed microwave, this does not necessarily inform what the power would be for each pulse.

Thoughts?

Well, the propulsive efficiency of the "advertised" experimental devices is very low.  For some reason, I seem to be the only person to put this in English:  The devices aim to convert electrical energy into linear momentum.  Therefore it is reasonable to consider the energy input as the analog of propellant.  While propulsive efficiency itself could be improved with a demonstration of the effect, it would make sense to crank up the input power.

Other than the pesky theoretical details, the thought to be "positive" results continue, after a decade or so of experimentation under wildly varying theories of operation, can barely be discerned from the underlying noise.

There have been a handful of suggestions up thread to increase the input power so as to increase the expected thrust results.  You aren't gonna make the Kessler run in a handful of *cough* parsecs on 4 to 20 mA, and I'm thinking you aren't gonna get "positive" results with such a small power input.

But hey.  What do I know? I'm just a gadfly.

NASA Eagleworks has run and still proposes to run these experiments in the future at much lower power levels than even Shawyer or the Chinese.  NASA has run these experiments at only 2.6 and 16.9 watts input power: less than the power required to light an incandescent light bulb (compare this with the Chinese and Shawyer at 1000 watts).

Quote from: Pathological science  http://en.wikipedia.org/wiki/Pathological_science
Pathological science is the process by which "people are tricked into false results ... by subjective effects, wishful thinking or threshold interactions". The term was first  used by Irving Langmuir, Nobel Prize-winning chemist, during a 1953 colloquium at the Knolls Research Laboratory.
....

The maximum effect that is observed is produced by a causative agent of barely detectable intensity

When asked by the audience (@59 minutes)

where is this technology going to be 20 years from now (2034) Dr. White says that he has no answer to that.

One doesn't get a sense of any great urge from NASA to really promptly advance this "Research" into anything (certainly not reminiscent of the late 1950's/early 1960's, if somebody would have asked where we were going to be in 20 years from then...)

"In 2008 the Russian Research Institute of Space Systems launched an experimental micro-satellite called Yubileiny (Jubilee) with a "non-traditional" engine which, according to Director Valery Mesnshikov, functions without ejecting reaction mass. Yubileiny (Jubilee), a Russian technology development satellite which was built by NPO PM to commemorate the 50th anniversary of the launch of Sputnik 1, the first artificial satellite to be placed into Earth orbit. It launched , 23 May 2008 aboard a Rockot rocket from LC-133 at the Plesetsk Cosmodrome. Launch was delayed from the end of 2007, and from earlier in 2008. It was a secondary payload to a cluster of three Gonets satellites, utilising the excess capacity of the carrier rocket.

However, it was later stated that "further developments" were needed and nothing further appears to be been published on Russian reactionless drives."

« Last Edit: 11/19/2014 02:45 PM by Rodal »

#### Rodal

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##### Re: EM Drive Developments
« Reply #3326 on: 11/19/2014 02:16 PM »
...
But hey.  What do I know? I'm just a gadfly.

#### Ron Stahl

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##### Re: EM Drive Developments
« Reply #3327 on: 11/19/2014 02:49 PM »
Well, the propulsive efficiency of the "advertised" experimental devices is very low.  For some reason, I seem to be the only person to put this in English:  The devices aim to convert electrical energy into linear momentum.
That is one interpretation, based upon certain explanations for the thrust being true and others not.  Generally though, any explanation that holds this view that this is a force transducer, leads to a violation of conservation.  The exception to this, is Woodward's theory which posits that this, if indeed it is generating Mach-Effects; is a gravinertial transistor, not a transducer.  It is not transforming electrical power into kinetic but rather, controlling the flow of inertial flux into and out of the active mass, and that therefore the vast bulk of the energy and power provided is not electrical but gravinertial.  This is why Woodward's theory alone does not violate conservation.  Also, it is why Woodward's theory alone posits hugely improved thrust to electrical power ratios than what we've seen--the power is not being transduced or converted into thrust.  It is merely controlling the flux that gives matter its mass.
« Last Edit: 11/19/2014 04:25 PM by Ron Stahl »

#### Ron Stahl

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##### Re: EM Drive Developments
« Reply #3328 on: 11/19/2014 03:43 PM »
When asked by the audience (@59 minutes)

where is this technology going to be 20 years from now (2034) Dr. White says that he has no answer to that.

One doesn't get a sense of any great urge from NASA to really promptly advance this "Research" into anything (certainly not reminiscent of the late 1950's/early 1960's, if somebody would have asked where we were going to be in 20 years from then...)

I think this is just Sonny being careful.  He's knows enough not to sound too enthusiastic.  And remember, this is a civil servant.  Unlike in private industry where we require results, NASA people can embark on a quest that lasts 50 years, and they often joke about how such and such a project is a "career-paycheck".  No different from the fusion research at the national labs.

Quote
"In 2008 the Russian Research Institute of Space Systems launched an experimental micro-satellite called Yubileiny (Jubilee) with a "non-traditional" engine which, according to Director Valery Mesnshikov, functions without ejecting reaction mass. Yubileiny (Jubilee), a Russian technology development satellite which was built by NPO PM to commemorate the 50th anniversary of the launch of Sputnik 1, the first artificial satellite to be placed into Earth orbit. It launched , 23 May 2008 aboard a Rockot rocket from LC-133 at the Plesetsk Cosmodrome. Launch was delayed from the end of 2007, and from earlier in 2008. It was a secondary payload to a cluster of three Gonets satellites, utilising the excess capacity of the carrier rocket.

However, it was later stated that "further developments" were needed and nothing further appears to be been published on Russian reactionless drives."

Russian propellantless drives are unusual in that they use two different kinds of hand-waving.  In the English speaking world, normally mad schemes have the ZPF wand waved over them to bless them and stop analysis of what is being proposed.  That trick works quite well.  In Russia they do the same, but they also sometimes use the "torsion physics" wand.  Since there is all of one physicist in the US who dabbles with Torsion Physics, there is really no one to do due diligence on such things.  I would just note that the Russian interest in twisting spacetime has been reported for many years, from weapons designs to propulsion, and there has never been demonstrated anything that remotely appears to give it any empirical authority.  It appears to be a scam from start to finish--same as ZPF and QVF physics.  However, the Torsion Field claims are still coming from Russia, from folks like Gennedy Shipov who really just has a Dean Drive but often convinces folks he has something real and useful.  Last I talked with Gennedy he said he had full funding in S. Korea.

http://en.wikipedia.org/wiki/Torsion_field_(pseudoscience)

http://en.wikipedia.org/wiki/Dean_drive

#### JohnFornaro

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##### Re: EM Drive Developments
« Reply #3329 on: 11/19/2014 03:56 PM »
Rodal!  Spot on!
Sometimes I just flat out don't get it.

#### Rodal

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##### Re: EM Drive Developments
« Reply #3330 on: 11/19/2014 04:39 PM »

I think this is just Sonny being careful.  He's knows enough not to sound too enthusiastic.  ....

Has he has been careful and not enthusiastic with his published conference papers extrapolating quick trips to Enceladus based on a completely unproven technology that he is running now and planning to run in the future at only 0.2% to 1.6% the power that even the Chinese and Shawyer have been running ?.

Has he been careful and not enthusiastic in hinting that the EM Drive results may be due to Quantum Vacuum interaction (whose force he predicted should be perpendicular to the E and B fields, therefore perpendicular to the measured force in the Eagleworks microwave cavity tests)?.

Or in proposing that there is an energy paradox even with conventional rocket engines using propellants?

But he must be careful and not too enthusiastic in orally answering a question as to where we could be in 20 years with this technology, asked by a youngster in a T-shirt during an informal internal NASA Ames presentation ?

If he believes that these EM propellant-less Drives can really propel a spacecraft in space, what are the big engineering challenges to be overcome during the next 20 years that make it impossible for him to answer the question?
« Last Edit: 11/19/2014 05:00 PM by Rodal »

#### Ron Stahl

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##### Re: EM Drive Developments
« Reply #3331 on: 11/19/2014 04:59 PM »

I think this is just Sonny being careful.  He's knows enough not to sound too enthusiastic.  ....

Has he has been careful and not enthusiastic with his published  conference papers extrapolating quick trips to Enceladus based on a completely unproven technology that he is running now and planning to run in the future at only 0.2% to 0.16% the power that the Chinese and Shawyer have been running ?.

Has he been careful and not enthusiastic in hinting that the EM Drive results may be due to Quantum Vacuum interaction (whose force he predicted should be perpendicular to the E and B fields, therefore perpendicular to the measured force in the Eagleworks microwave cavity tests)?.

Or in proposing that there is an energy paradox even with conventional rocket engines using propellants?

Or in proposing that the negative mass necessary for the Alcubierre drive could be as small as the size of the Voyager probe?

But he must be careful and not too enthusiastic in orally answering a question as to where we are going to be in 20 years with this technology, asked by a youngster in a T-shirt during an informal internal NASA Ames presentation ?

I agree with your sentiments here.  This is why I don't understand the fascination with the E-M stuff when the M-E stuff is much more promising.  Trust me, I could add dozens of violations of common sense and scientific protocol to the short one you've just made.   The question is really, is Sonny representative of the entire propellentless "Space Drive" field?  The short answer is "yes, with one exception" and it is the exception--the thing that never gets the ZPFers support--that is noteworthy.

You seem to be surprised, but the ZPFers have completely dominated this field now for more than 20 years, and successfully kept everyone else out of funding.  This nonsense goes back before the very first days of the Breakthrough Propulsion Physics Project in the '90's and has not stopped since.  Marc Millis is a ZPFer.  Eric Davis is a ZPFer.  Sonny, General Pete Worden (Director of NASA Ames, who introduced Sonny in the above vid), Creon Levit--all ZPFers.  So where is the surprise coming from?
« Last Edit: 11/19/2014 05:00 PM by Ron Stahl »

#### Mulletron

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##### Re: EM Drive Developments
« Reply #3332 on: 11/22/2014 04:23 AM »
After a few days of really thinking hard about the build, here's what I'm planning:

I'm going to build the Casimir cone I designed, described and posted way back in the thread. I can do this pretty easily using copper sheet from http://basiccopper.com/thicknessguide.html or similar places. Building my own design seems logical and it is in keeping with the proposed theory common to Cannae(long vs short tube) and Shawyer's design(truncated cone); using dielectrics in asymmetrical cavities. Building my own design seems appropriate since I need to test all the ideas I've floated (informed by many others) about how EMdrives/Qthrusters/METs/MLTs/ACTs, whatever... might work and/or work better.

All the above devices are very similar in the most fundamental way, but their respective theories (therefore engineering) are what diverge the most.

An added bonus of using the 45 degree cone is that building it is as simple as twisting, soldering, and trimming lightweight copper sheet.

Given the nightmares of finding resonant frequencies of tapered frustums, especially with limited resources, another added bonus is that the 45 degree cone approach is infinitely tunable by inserting copper discs of varying diameter into the structure. Given that a resonant cavity must have a resonant mode at the frequency you're trying to excite it with in order to couple sufficiently, I think this approach will make things easier to work with. This way I don't have to build a lot of things. I can just build one thing and make subtle changes to it. It isn't easy for me to just get stuff here quickly because I'm currently living overseas and there isn't a Home Depot for thousands of miles. The local Leroy Merlin is as good as it gets. So I can get stuff, it just takes longer.

I'm hoping to inspire other folks out there to try their own experiment as well. Stay tuned.

I'm getting bored waiting on the "Anomalous thrust......" part II paper to come out.
« Last Edit: 11/22/2014 04:59 AM by Mulletron »
Challenge your preconceptions, or they will challenge you. - Velik

#### JohnFornaro

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##### Re: EM Drive Developments
« Reply #3333 on: 11/22/2014 04:50 AM »
After a few days of really thinking hard about the build, here's what I'm planning:...

Hey Mull!  Putta hot dog in there for me will ya?

Sorry, couldn't resist.

Been Dancing

Then went to the mixologist's birthday party.  Gittin' kinda late.  Lemme know when the h-d's are ready...
Sometimes I just flat out don't get it.

#### Mulletron

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##### Re: EM Drive Developments
« Reply #3334 on: 11/22/2014 05:49 AM »

Challenge your preconceptions, or they will challenge you. - Velik

#### IslandPlaya

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##### Re: EM Drive Developments
« Reply #3335 on: 11/22/2014 06:01 AM »
You can't have a sharp end of your copper cavity though. You should try!
Good Luck mate! Really, I think you are ace!

#### IslandPlaya

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##### Re: EM Drive Developments
« Reply #3336 on: 11/22/2014 06:11 AM »
Am thinking or trying something with my friend and a copper frustum with a 900w magentron (out of a uWave oven of course.)
Planning to suspend the whole setup on piano wire...
What we hope is that we get a nice deflection cos of the high power.
Is this a good way to go about it?

#### aero

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##### Re: EM Drive Developments
« Reply #3337 on: 11/22/2014 06:19 AM »
I was beginning to worry that everybody else had quit.   I haven't quit but stuff gets in the way. I made an all night run night before last in order to make a movie of the field patterns. I got a whole slew of PNG files but the software that was supposed to convert them to a movie, won't! The stupid program i'm using spits out the PNG files at 32 MB each and it made about 100-200 of them. They're even to large to post and the quality isn't as good as I'd like.

Today I decided I had to get email up and running on my Ubuntu OS because I can't communicate to the discussion group without. That took a long time and then when I finally shut down and logged onto Windows, it was broken, couldn't identify user profile or some such thing. Couldn't repair it so restored from a save point. Lucky for me the machine made a save point last Sunday..

Back to trying to model the cavity. Reprogramming a lot of it so that it will be completely scalable with a characteristic length. About 7:00 pm I finally made a short run that produced something that looks line the Brady cavity, in profile. It's got some gaps that I don't like but its not so big a file, I'll try to attach it.

Oh, I should mention that the end copper sheets are not to scale. With this image I was trying to see how well my model parts fit together and the 0.002" copper ends don't show up very well unless I increase the grid resolution - doing that increases the run time by a power of two and I want to finalize the model this week. It already runs 10 minutes just to make this simple sketch with very limited RF excitation.

Encouragement to you.
« Last Edit: 11/22/2014 07:04 AM by aero »
Retired, working interesting problems

#### Ron Stahl

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##### Re: EM Drive Developments
« Reply #3338 on: 11/22/2014 01:47 PM »
Am thinking or trying something with my friend and a copper frustum with a 900w magentron (out of a uWave oven of course.)
Planning to suspend the whole setup on piano wire...
What we hope is that we get a nice deflection cos of the high power.
Is this a good way to go about it?

The magnetrons used in microwave ovens typically cost \$25 on EBay and range up to about 1kW power.  The trouble with them is, they are not intended for high Q applications and will burn out if attached to a resonator.  I first learned of this in discussions with Paul March in 2007 when he and Sonny built their first Shawyer resonator with funding from Gary Hudson.  According to Paul, what you need is a continuous wave magnetron, which back then was much more difficult to find and I think the only stuff available on a budget was from Russia.  (Paul actually asked me to help him find one which proved to be a difficult task.)  Now they're pretty commonplace though, I have no idea why.  My guess is they have a commercial application in inductive heating or some such but I'm not familiar with it.

http://www.rell.com/products/Magnetrons/Magnetron-CW.html

As far as suspending it from a wire, that's a common practice.  I would just note to you, that especially if the wires are the power leads, clearly demonstrating any action one might observe is not thermal and result of the leads, is a huge task.  This is what Tom Mayhood faced in his masters thesis work back in the 90's and he was never successful clearly ruling out that what he had was thermal.  http://www.otherhand.org/home-page/physics/graduate-studies-in-physics-at-cal-state-university-fullerton/  And I would just note again, that none of these hobbyist efforts is worth anything if you can't rule out spurious sources.  There are many dozens of experiments that have been done over the last couple decades that are clearly useless, as they don't cope with the actual science of eliminating such possibilities.

So again I'd just note, that it is almost impossible for me to see how any low thrust experiment could be useful without providing vacuum.  It doesn't need to be much vacuum and it doesn't need to be expensive, but you'll be gluing lots of acrylic together to a hard line to a chamber, and you'll want to pay the cost of a decent roughing pump like the Welch Duoseal 1400.  If there were a way to do a decent experiment without vacuum, trust me I'd be all for that, but I don't see one.

As to thrust balance, there are lots of different designs.  The suspension notion has some merit, but if one is to completely eliminate thermal as a spurious source, those wires are serious trouble.  What I think  would be much better, and perhaps in many ways easier; would be to use magnetic suspension.  This is surprisingly easy to do and apart from the stray magnetic fields this generates, it solves a host of issues.  MIT is doing this and I have to say, I like it!  But when you're using these powerful fields for suspension, you both need to make judicious use of something like Mu metal during your testing (once you have thrust) to show you don't have b field coupling, and you'll need to make a fully powered test where your dummy load is as perfect as it can be.  For the MET, this is simple: just alter the phase between the 1w and 2w portions of the power supply as this should not matter much for coupling and so provide a good dummy.  For thruster designs that use a single frequency component, the task is harder.  You'll need to think on that.  Here though for your consideration is a small vid of the MIT Space Propulsion Lab balance in acton.  It's a fun setup.  There's nothing like floating stuff in the extra bedroom.  :-)

« Last Edit: 11/22/2014 03:41 PM by Ron Stahl »

#### JohnFornaro

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##### Re: EM Drive Developments
« Reply #3339 on: 11/22/2014 02:37 PM »
Am thinking or trying something with my friend and a copper frustum...

I hope your friend's ok with that...
Sometimes I just flat out don't get it.

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