I had one of these toys when I was a kid. As the video shows, once you started the little top spinning, it kept on spinning indefinitely - or at least until the battery hidden in the base ran flat.
Inside the base was the aforemented battery, which appeared to power nothing but a solenoid arranged with its axis vertical, directly below the center of top’s play area.
The top has a magnet in it; if you set it on the play area without spinning it, it was strongly attracted to the center, directly above the solenoid.
So how did it work? How was the magnet (i.e. its field lines) arranged inside the top? And how did it interact with the base’s solenoid so as to accelerate the top’s spin rate whenever it danced near the center of the platform?
You turn the solenoid on when the top’s approaching the center and turn it off when the top is moving away. This pumps energy into the oscillatory motion, similarly to pumping on a playground swing. The oscillatory motion in turn feeds into the rotational motion.
They specifically describe a “radially-oriented magnetic field” inside the top, and describe the solenoid as somehow delivering torque (rather than a simple linear attractive force).
I can see a way in which your explanation would work: if the point on which the top spins has a non-zero radius of curvature, and if the top is leaned over, then a lateral force on it in the direction of its lateral motion will tend to accelerate the rotation (due to a torque which is the frictive force at the point of contact multipled by the offset between the point of contact and the axis of rotation, which is non-zero since it’s leaned over).
But are you sure your explanation is correct, or is that just a theory? Is the Dave’s Cool Toys explanation just a bunch of BS, or is the solenoid somehow inducing electrical currents that actually cause torque to be delivered throughout the body of the top (as opposed to just at the tip as described in the previous paragraph)?
I think the Dave’s Cool Toys explanation is just BS. The surface of the toy is concave. The magnet switches on when the top is at the bottom of the dish and appears to do nothing except push the top up the sdes of the dish and gravity speeds up the spin as it comes back down to the bottom.
What I posted was just educated guesswork. The “official” explanation might be based on a grain of truth, but if so, it’s been distorted beyond recognition: A “radially-oriented magnetic field” is impossible; anything that might plausibly be described as such couldn’t be torqued; a vertically-oriented solenoid won’t directly put a torque on anything above it anyway; opening a switch would power the solenoid down, not power it up; the top doesn’t need a torque to spin away from the center, just momentum.