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Old 02-15-2019, 10:33 PM
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spacecase0 spacecase0 is offline
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Join Date: Nov 2014
Posts: 461
Originally Posted by swallabat View Post
At 8:51 at he bottom of the page he quotes a motor speed of 8000rpm (ish).

The recordings of it working would sound way more impressive if it was spinning that fast.

Also the quoted speed I don't think is a harmonic of 50Hz AKA 3000rpm.. And since at least one disc is being spun by an AC synchronous motor it needs to be... I'm no expert on synchronous motors, I only have a faint understanding so I could be correctable there.

I do have it on good authority that "ours wobble" (at least our early ones did) so it does have that going for it!

so, I was pretty sure that 8K RPM was not something a synchronous motor can do, so I checked.
and after thinking about the stable points, I doubt even 3K RPM can be managed

I have played with them 25 years ago,
so needed a reminder of what most of them are
but pretty sure that with air drag 3K rpm is not happening,
not only that, but you would have seen the start sequence even with a standard Synchronous motor in the video

Last edited by spacecase0; 02-15-2019 at 10:38 PM.
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