Sorry if I confused you.Are we to have axions or MiHsC?Both are speculative but only one or none can be true, I think.What do you chaps think?
Quote from: Mulletron on 02/15/2015 07:48 amQuote from: Star-Drive on 02/15/2015 04:17 amFolks:In the meantime, lets ask why 60 watts of relatively harmonic free sine-wave RF power at the 1,937.118 MHz AKA the TM212 resonant frequency in this copper frustum cavity, can only generate a paltry ~60uN, whereas the Chinese claimed to have produce 160,000uN using just ~150 watts of 2,450 MHz RF signals from a magnetron? The magnetron RF signal source that is anything but a pure sine-wave generator, that instead has a modulated FM bandwidth of at least +/-30 MHz that is also concurrently amplitude modulated (AM) with thermal electron noise. Taking a critical look at this question, and knowing that the spectral shape of a magnetron looks like (see below) compared to a CW spike. It seems evident that a CW spike isn't the best waveform to use if you want to maximize thrust. Dollars to donuts says the Chinese are making full use of the available bandwidth of their resonant cavity by using that noisy magnetron. Magnetrons have lots of phase noise too. You can't easily use them on phased array radars because of that for example. Now to put this idea to test, Q: What is the bandwidth of the resonant cavity and what is the 90 percent power bandwidth of the signal you are driving it with? What kind of sig gen are you using? Can it do FM? Can you do any advanced waveforms like a PSK waveform? Do you have a way to produce wideband noise or a spread spectrum carrier for your testing? Can you do any waveforms like at the bottom?Also during researching other possible theories which could explain Emdrive we found ample literature stating that molecules acquire a kinetic momentum during the switching of the magnetic field as a result of its interaction with the vacuum field. If correct, that may well be a very significant lead. So that raises the question, how does one increase the switching rate? What about phase shifting? http://en.wikipedia.org/wiki/Phase-shift_keyingPhase shifting seems important. https://www.viasat.com/files/assets/web/datasheets/EBEM_MD-1366_043_web.pdfOne of these driving your amp would be helpful. They go up to 2ghz.Mulletron:When using our current 14mm loop antenna optimized for the TM212 resonance at 1,937.118 MHz in our copper frustum, there were four RF resonances spaced +/- 30 MHz around the 2.45 GHz center frequency. And I assume that would also be the case using a higher power slot antenna in a similar location as the Chinese and Shawyer have done with their frustum resonant cavities. So yes, a wide bandwidth RF source seems to be called for and one that can be both AM and FM modulated at the same time. From my readings to date, that appears to be a hard nut to crack for solid state RF amplifiers at the desired kW power levels due to their limited RF power bandwidth capabilities, so we may be forced into using magnetrons and just learn how best to feed their 4-to-20 kV high voltage anode requirements while working in a hard vacuum. However the more difficult problems are finding ways of reducing their mass and size so we can "fly" them on our torque pendulum. Cooling the magnetrons in a hard vacuum is also another problem we need to deal with since air cooling is out of the question and liquid cooling is a giant pain to deal with as well. About the only other way to cool these beasts in a hard vacuum is to use phase change material like paraffin wax that could give us several minutes of run times before we had to let the accumulated heat in the paraffin radiate to the vacuum chamber walls. BTW, the paraffin wax phase change cooling was used to good advantage on the lunar moon buggy used by NASA astronauts during their lunar explorations in the late 1960s and early 1970s during the USA Apollo Moon program.Best, Paul M.
Quote from: Star-Drive on 02/15/2015 04:17 amFolks:In the meantime, lets ask why 60 watts of relatively harmonic free sine-wave RF power at the 1,937.118 MHz AKA the TM212 resonant frequency in this copper frustum cavity, can only generate a paltry ~60uN, whereas the Chinese claimed to have produce 160,000uN using just ~150 watts of 2,450 MHz RF signals from a magnetron? The magnetron RF signal source that is anything but a pure sine-wave generator, that instead has a modulated FM bandwidth of at least +/-30 MHz that is also concurrently amplitude modulated (AM) with thermal electron noise. Taking a critical look at this question, and knowing that the spectral shape of a magnetron looks like (see below) compared to a CW spike. It seems evident that a CW spike isn't the best waveform to use if you want to maximize thrust. Dollars to donuts says the Chinese are making full use of the available bandwidth of their resonant cavity by using that noisy magnetron. Magnetrons have lots of phase noise too. You can't easily use them on phased array radars because of that for example. Now to put this idea to test, Q: What is the bandwidth of the resonant cavity and what is the 90 percent power bandwidth of the signal you are driving it with? What kind of sig gen are you using? Can it do FM? Can you do any advanced waveforms like a PSK waveform? Do you have a way to produce wideband noise or a spread spectrum carrier for your testing? Can you do any waveforms like at the bottom?Also during researching other possible theories which could explain Emdrive we found ample literature stating that molecules acquire a kinetic momentum during the switching of the magnetic field as a result of its interaction with the vacuum field. If correct, that may well be a very significant lead. So that raises the question, how does one increase the switching rate? What about phase shifting? http://en.wikipedia.org/wiki/Phase-shift_keyingPhase shifting seems important. https://www.viasat.com/files/assets/web/datasheets/EBEM_MD-1366_043_web.pdfOne of these driving your amp would be helpful. They go up to 2ghz.
Folks:In the meantime, lets ask why 60 watts of relatively harmonic free sine-wave RF power at the 1,937.118 MHz AKA the TM212 resonant frequency in this copper frustum cavity, can only generate a paltry ~60uN, whereas the Chinese claimed to have produce 160,000uN using just ~150 watts of 2,450 MHz RF signals from a magnetron? The magnetron RF signal source that is anything but a pure sine-wave generator, that instead has a modulated FM bandwidth of at least +/-30 MHz that is also concurrently amplitude modulated (AM) with thermal electron noise.
Dear aero;Superb! My congratulations. Clearly, until proven otherwise, we now have to regard the anomalous results as a function of E&M interactions with the walls of the vacuum chamber.
We can forget about exotic theory and consider that the thrust force likely results from a little understood characteristic of evanescent waves and the forces they generate. Please pardon me if that steps on anyone's toes
Did anyone digest the reported facts that the device's thrust can be reversed simply by changing the resonant mode and/or the placement of the dielectric puck?@Paul March....Which modes were reverse?
However, one can also reverse this thrust vector for this copper frustum by just changing which excited resonant mode is used and/or mounting the dielectric discs at the large OD end of the cavity instead of the small OD end, see attached resonant mode map.
Quote from: Star-Drive on 02/14/2015 09:06 pmHowever, one can also reverse this thrust vector for this copper frustum by just changing which excited resonant mode is used and/or mounting the dielectric discs at the large OD end of the cavity instead of the small OD end, see attached resonant mode map. This is non trivial.
This is hardly a workable theory of operation. There is nothing to back it up. Just conjecture. Not even one citation. Did anyone digest the reported facts that the device's thrust can be reversed simply by changing the resonant mode and/or the placement of the dielectric puck?
And by the way, isn't a changed resonant frequency or mode the natural result from moving the dielectric from one end to the other in the tapered cavity?
aero - I heartily encourage you to keep at it.
...I have also cited this paper, http://wwwsis.lnf.infn.it/pub/INFN-FM-00-04.pdf several times. No feedback what-so-ever. ....
Do we know if MEEP adequately models the reactive near field? I don't see signs of it in the plots, but I do not trust my intituition, so things may be fine, but I thought I would ask.
Ok...time for me to embarrass myself here yet again. Assuming for the moment, this device works not just in a vacuum chamber, but in space...1) The frequency necessary to generate thrust varies with the internal (?) temperature.
2) The longer this device runs, the hotter it gets - 'Star Drive' reports major heating issues with low power test setups running for a few minutes (?) at a time. We are talking about a space version running nonstop for months or even years. To me, that sounds like a pretty extreme temperature increase - hundreds (?) thousands (?) of degrees, maybe. So...would continual high temperatures damage the frustum over time? Or other parts of the device?And might not the high temperatures...hmmm...act somehow to 'put the brakes' on the continual acceleration - increase to the point where the required frequency for thrust becomes unattainable, or at least reduced?
Te ------------------- ----- --- -- -Tc ---------
Also...heat is energy, and this device, run for long periods in space, looks to produce a lot of heat. Could a portion of that heat be tapped and converted into electrical power, thus reducing the over all power requirements? Talking supplement here, not perpetual motion.Ok, time to quit while I'm behind.