As promised, here is my video of the first test of my mechanical fulcrum. It will be used to show relative weight change in addition to a digital scale. Had some concerns about the digital scale alone, possibly being affected by the RF. The fulcrum is simply designed to be an alternate test method.
Need to go visit today, but before I did I thought you would like to see the first draft of the segmented, multi end plate, perforated copper frustum. Using clasps to hold the to parts together and they should be quite secure and sturdy. The large endplate will be cupped out with an english wheel the small top plates will be flat.Shell Waiting to see the patterns from Aero to finally decide on the antenna orientation. BTW Aero great work!!!Edit: forgot pic...
Dear all, In 2012 the first solid state maser based on a pentacene doped t-terphenyl crystal was invented at the Imperial College London after 60 years of unsuccessful attempts to build a maser that is capable of emitting at ambient conditions with considerable output powers.It's maximal output power in Continous mode is 0.1 mW and approx. 1 W in a microsecond pulsed mode.Now what do you think about the following?What if we manage to amplify such a 1 W peak power pulse with a pulse duration of a microsecond and amplify it with a klystron to much higher peak powers?If the effect that shortened the optical path length of the laser pulse (as measured from laboratory frame), is dependent on the electric field strength, then we could amplify this effect for the duration of the pulse.Now IF, the laser pulse is just triggered to pass through the frustum just when the pulse is being reflected, we should see a much stronger effect of path length shortening... well at least IF the assumption that the effect is dependent on electric and magnetic field strength is correct...
The final 8 .pngs, Yang cavity electric excitation, antenna length = 0.2 wavelengths, total run 16 periods with .png output every 0.2 periods.This set of images is much better behaved than the magnetic excited cavity images. Don't know why. Unfortunately, with the background changing color as it does, a movie wouldn't be very viewable. IMO I'll go ahead and upload this complete set to my Google Drive in case anyone is interested in looking at them all together. I point out that there are patterns that appear across the whole set that don't pop out at you when looking at only a small subset of the images.
Quote from: aero on 06/21/2015 07:49 pmThe final 8 .pngs, Yang cavity electric excitation, antenna length = 0.2 wavelengths, total run 16 periods with .png output every 0.2 periods.This set of images is much better behaved than the magnetic excited cavity images. Don't know why. Unfortunately, with the background changing color as it does, a movie wouldn't be very viewable. IMO I'll go ahead and upload this complete set to my Google Drive in case anyone is interested in looking at them all together. I point out that there are patterns that appear across the whole set that don't pop out at you when looking at only a small subset of the images.This is great !!!It predicts mode shape TE012, same mode that my exact solution predicts
...I am glad to hear that! Emphatically GLAD to hear that.
I attach my report first attachment below, titled:Cut-off of Resonant Modes in Truncated Conical CavitiesConclusions1) It is nonsense to use a cylindrical waveguide cut-off formula to predict cut-off of mode shapes in a truncated cone. Truncated cones cannot have constant electromagnetic fields in the longitudinal direction, thus the use of cylindrical waveguide formulas (which assume constant cross-sections) for truncated cone cavities is nonsense.2) Truncated cones show an absence of sharp cut-off frequencies. Cut-off occurs at geometries that are close to a pointy cone, at small base dimensions that are much smaller than what is predicted by cylindrical waveguide cut-off formulas. 3) On the contrary, continuing the cone beyond the small diameter at which cut-off would occur (according to the cylindrical formula which is inapplicable to the cone) leads to significantly higher amplitudes of the electromagnetic fields. The amplitude of mode TE013 actually increases by a factor greater than 2.5 from its original amplitude. While mode shape TE013 has the smallest amplitude compared to TE011 and TE012 at the initial dimensions, as we reduce the small base it becomes the mode with the highest amplitude4) The “half-wavelength” nearest the apex gets longer as it approaches the apex.5) For the particular geometry in the examples in this report, cut-off of mode shape TE011 occurs when the small base is reduced to only ¼ of its original dimension. The cut-off condition based on a cylindrical waveguide incorrectly shows that TE011 should have been cut-off at a much larger base diameter (at 0.90 the original dimension instead of 0.25 the original dimension).6) Cut-off of mode shape TE012 and TE013 occurs when the small base is reduced to only 1/5 of its original dimension. The cut-off condition based on a cylindrical waveguide incorrectly shows that TE012 and TE013 should have been cut-off at a much larger base diameter (at 0.90 the original dimension instead of 0.20 the original dimension).7) Continuing the cone up to distances much closer to the apex also results in lower phase shift and higher geometrical attenuation of the electromagnetic field in the longitudinal direction. When the small base is reduced to ½ the original size: a) the (dimensionless) geometrical attenuation is increased by a factor of 28 times from 0.1 to 2.8, and b) the phase constant is increased by a factor of 2 from 0.5 to 1. Hence it looks like very large changes can be accomplished by simply reducing a truncated cone’s small base so that it is much closer to the cone’s apex, and this can be done without incurring cut-off, and achieving a higher amplitude to boot. Thus continuing the cone beyond the cylindrical cut-off frequency may result in very interesting behavior. All the EM Drive formulas (McCulloch’s, @Notsosureofit’s, and Shawyer’s) predict greater thrust with a larger difference between the diameters of the big and the small bases of the truncated cone. Therefore these formulas point towards the direction that the ideal geometry would be one with a small base diameter. Yet such a geometry has not been explored up to now, apparently due to Shawyer’s constraining the small base diameter to be larger than the diameter that results in cut-off according to the cylindrical waveguide formula. This report shows that this constraint is nonsensical, as truncated cones resonate (and at higher amplitude) with significantly smaller base diameters. This report shows that the small based diameter could be reduced to at least ½ of its present size, and perhaps to 1/5 of its present size.
Quote from: aero on 06/21/2015 08:04 pm...I am glad to hear that! Emphatically GLAD to hear that.At what frequency is your cone being excited in those images?
Quote from: Rodal on 06/21/2015 08:16 pmQuote from: aero on 06/21/2015 08:04 pm...I am glad to hear that! Emphatically GLAD to hear that.At what frequency is your cone being excited in those images?Drive is set at 2.45 GHz. I haven't made any resonance runs in this excitation/antenna configuration. I could do that.I could, but I'd like to take the time to digest your paper and perhaps model a cavity designed as you suggest. For flat end plates, making a model would be very simple. For "spherical section" end plates I'd need to write a new control file but that wouldn't be so difficult as I've done it before. Do need to know the radii though, and the best half angle.
...electromagnetic interaction of the supply wires? I wasn't aware copper was that magnetic. I mean, unless I don't understand what you are saying. Interaction with what?
Quote from: rfmwguy on 06/21/2015 06:44 pmAs promised, here is my video of the first test of my mechanical fulcrum. It will be used to show relative weight change in addition to a digital scale. Had some concerns about the digital scale alone, possibly being affected by the RF. The fulcrum is simply designed to be an alternate test method....Thank you for posting this !Great work.1) I don't know whether it is parallax due to the camera (I would like your feedback) but I saw bending of the wooden beam. Is the wooden beam compliant enought that the two water bottles are producing visible bending of the beam simply-supported by the knife edge? If so, you may have two sources of oscillation:a) lowest frequency oscillation: rigid body rotation of the beam around the knife edgeb) higher frequency oscillation: beam bending oscillations (there are an infinite number, but unless it was parallax I clearly saw beam bending : the first mode)Couldn't see whether the oscillations were due mainly to rigid body rotation or to bending, but based on the very long period of oscillation, it must be mainly due to rigid body rotation of the beam.2) If you cannot wait for the oscillations to dampen (>30 minutes ?) in the future, you may have to also include (oil or water) damping.
As promised, here is my video of the first test of my mechanical fulcrum. It will be used to show relative weight change in addition to a digital scale. Had some concerns about the digital scale alone, possibly being affected by the RF. The fulcrum is simply designed to be an alternate test method....
Dear rfmwguy, a table to put the camera down on may make adjusting things easier as it will allow you to use both hands.
Quote from: A_M_Swallow on 06/21/2015 10:36 pmDear rfmwguy, a table to put the camera down on may make adjusting things easier as it will allow you to use both hands.A table or a tripod. Unless you are filming with your cell phone
Dr. Rodal,What drive frequency do you propose? Shown is ~ 1.95 GHz. It's an extended Brady cone, with small end = 0.25*big end. That is, sf= 0.25, small = sf * big, and new_height = height*big*(1-sf)/(big-small). I guess I'll make a resonance run to see if something comes up.