I remember seeing Chinese ivory balls as a six year old at the Sydney museum, my reaction was WTF !......and HTF do they make these things !.
Dan
My LTspice model implements:
BL(i)
BL(x)
Eddy current BL(e)
coil braking eddies BL(iv)
Steel parts saturation
Surround Kms(x)
Spider Kms(x)
Air resistance Rms(v)
Steel saturation R(i)
But it is messy.
BL(i)
BL(x)
Eddy current BL(e)
coil braking eddies BL(iv)
Steel parts saturation
Surround Kms(x)
Spider Kms(x)
Air resistance Rms(v)
Steel saturation R(i)
But it is messy.
Looks interesting. Is it the one you discussed about a half year ago (voltage, current, JN drive discussion).
Yes, after all that work it's not as if you just forget about it and make a new one the next year.
I was looking at insertion of a small current sense resistor resulting in reduction of acoustic distortion Richard showed. We may have a better view of the mechanisms with a more robust model you have.
It’s called progress Scott!
Reminds of the video I saw about the team that goes around maintaining the Taj Mahal where the guys making replacement tiles still use the ancient technique of an abrasive wire and pedal power plus flywheel to cut the stuff. No lasers or modern electric tools.
🙂
Is it posted up somewhere?
Clearly a huge effort on your part but I’m wondering if it’s not really a job for Mathcad or perhaps something written in Python since you have a huge array of graphics and graphing functions plus some serious math modules.
(My youngest has spent the last 8 months getting to grips with it and is turning out some seriously professional looking stuff already. I on the other hand have just stuck with C++ for embedded stuff - no clue about writing stuff for the PC).
🙂
Hunting around on the web for free EM field simulation tools I found this
openEMS – A free and open electromagnetic field solver – Open Source Imaging
More to do with MRI, but interesting nevertheless
Then there’s femm 2D here
Finite Element Method Magnetics: HomePage
Hunting around on the web for free EM field simulation tools I found this
openEMS – A free and open electromagnetic field solver – Open Source Imaging
More to do with MRI, but interesting nevertheless
Then there’s femm 2D here
Finite Element Method Magnetics: HomePage
IMO SOTA is not in this thread, but here 😉:
Transducers - Purifi
I some times feel in this thread like at the Veteran Car Show, which I like BTW and going to visit one this very Saturday 🙂.
Transducers - Purifi
I some times feel in this thread like at the Veteran Car Show, which I like BTW and going to visit one this very Saturday 🙂.
Thanks.
I note third is 20db below fundamental at 30 Hz.
SOTA perhaps, that is prelim info from the write up.
In light of the measurement I just provided, have they ever done an Ls/Rs sweep with the voice coil locked in various positions?
I ask, as a standard solution to Le(x) is the shorting ring added to magnet side excursions to balance out the inductance drop for forward motion decoupling from the magnetic circuit. As I pointed out half a year ago, stabilizing Le(x) in this fashion comes at a cost, that being increasing losses at high frequency during excursion behind the front plate.
I suspect that if they had solved that, there would be a pending patent. So, while it looks good and the write up says all the correct things, I suspect they have not solved that which we have been discussing.
Indeed, they did not provide any two tone IM measurements of the caliber as that you posted back in last discussion. I wonder how they would fare?
Ps. It would also be interesting to determine if any speaker Manu people peruse sites and discussions like ours to advance the cause. I would hope so, even if they are not allowed to state such.
Jn
I note third is 20db below fundamental at 30 Hz.
SOTA perhaps, that is prelim info from the write up.
In light of the measurement I just provided, have they ever done an Ls/Rs sweep with the voice coil locked in various positions?
I ask, as a standard solution to Le(x) is the shorting ring added to magnet side excursions to balance out the inductance drop for forward motion decoupling from the magnetic circuit. As I pointed out half a year ago, stabilizing Le(x) in this fashion comes at a cost, that being increasing losses at high frequency during excursion behind the front plate.
I suspect that if they had solved that, there would be a pending patent. So, while it looks good and the write up says all the correct things, I suspect they have not solved that which we have been discussing.
Indeed, they did not provide any two tone IM measurements of the caliber as that you posted back in last discussion. I wonder how they would fare?
Ps. It would also be interesting to determine if any speaker Manu people peruse sites and discussions like ours to advance the cause. I would hope so, even if they are not allowed to state such.
Jn
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The Chinese have infinite patience, I'm sure they can sit out the one year left of a term.
No, it is not. Recall you stated the secondary flux cannot be opposite the primary, as it can "use it all up", leaving no magnetizing flux. Then Richard chimed in saying he thought something was amiss in my explanation..
As depicted in the linked paper (figure 2), the secondary flux is opposing the primary, this is as stated in Lenz's law, something you also claimed does not exist.
Both of these statements are forever locked in this thread, you can't remake history (even though you try).
If you had learned transformer theory correctly, you would know that the secondary opposing flux does not "consume" the magnetizing flux. It's existence is the reason the primary draws more in phase current from the source. That is precisely how power is transferred through the core.
What does shock me however, is in this day and age somebody has to actually write a paper that explains transformer action.. sigh, I learned this stuff back in '74 and it was ancient history then...
jn
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I've copied your salient statements for review. Not the entire post, just the shall we say, "interesting statements". No intent to misinterpret here, just what you said.
And, wait....did you just refer to Lenz's law? You just said it is actually not a law on it's own...
jn
Interesting to hear that..so would Emil.
See Lenz's law..
It opposes the rate of change. That is Lenz's law, and that is what I stated.
Please learn transformer theory.
And, wait....did you just refer to Lenz's law? You just said it is actually not a law on it's own...
jn
Elmer is always worth a look:
https://www.csc.fi/web/elmer
it's an open source multiphysics finite element package.
I haven't posted it anywhere and probably won't if I can't clean it up. It's just a mess of behavioral sources and would require significant reverse-engineering to understand it.
I generally agree but if the problem is posed with symbolic equations, when you add any non-linearity there are in general no solutions to the resulting differential equations. You really need FEM or a sparse matrix package which is all SPICE is.
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