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[email protected] pfjw@aol.com is offline
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Default mag-lev-turntable

On Friday, November 11, 2016 at 10:15:18 AM UTC-5, Mark Storkamp wrote:

let's see, how many things can go wrong here.


https://www.dropbox.com/s/huq5ehstso...tion.docx?dl=0

This is my wildly speculative speculation on how this system could work and be effective. Some points:

a) Neodymium magnets are wildly powerful. And can be shaped more efficiently than many other materials.
b) By offsetting the suspension rings as shown, the forces centering and keeping the platter level would be very strong - certainly stronger than most suspension springs for that matter.
c) And there would be negligible elastic forces - that is, no wobble or bounce. That window fan would not have a chance. Damping, similarly.
d) The wow and flutter issue, though very real, would be pretty much eliminated by the mass of the platter (considerable) coupled with the very negligible mass of the drive motor.
e) As the platter is essentially frictionless, it would not take much to keep it running once started. I would anticipate a few seconds of start-up, but after that, gyroscopic effects would contribute to leveling and to speed control. The couple of grams on the stylus, again, would not have a chance..
f) The soft shut-down is already addressed. There is an on-board soft shut-down capacity that will raise the posts and lift the stylus.
g) As to magnetic fields - consider that both the suspension field and the drive fields are static relative to each other. Meaning that there will be very little generated by way of stray fields, and that the platter, if properly designed, will be enough to shield the cartridge. Considering what goes on inside my HK/Rabco without ill effect, or my Revox B295, this would be low on my worry-scale.

Again, this is a neat trick, not something I intend to purchase. But a neat trick that appears to be both possible and reasonable to execute.

Peter Wieck
Melrose Park, PA