Just before Christmas I bought an induction powered illuminated 
spinning top.. . It cries out to be used to power a propellor clock or 
similar. ALL the hard work done.

Round base about 100mm across with lip.
Top has R + G + B  separate LEDs which illuminate when held over base. 
Spin top and place on base and it accelerates up to around 1000 rpm 
and spins indefinetely with the LEDs brightly lit.

It appears that the base makes a rotating magnetic field that drives 
the top's rotation and also induces power into the top - possibly 
using the slip frequency betwixt top and field. LEDs are bright 
whether stationary or spinning. A propello    r clock could be based 
on this with ease.

I've had a quick look inside the base (visual only) and got a general 
idea of what they are doing. Haven't looked inside the top yet.

Sells retail for $NZ30 = about $US20, which is far more than it's cost 
to make in China but a good price given its novelty value and ability 
compared to other executive toys. All sorts of extensions to this 
general capability suggest themselves.



        Russell 

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