LED Spinner Kit
This is a circular PCB which has a long screw spacer through its centre at right angles to the plane of the disk. The PCB is spun about the screw axis like a top. A sprung switch closes under centrifugal force when the PCB is spun. The switch activates a circuit that turns on a line of LEDs. The LEDs are supposed to light up brightly enough to appear as concentric circles of light. See the left hand image above, taken from the advert on AliExpress advert shows how things are supposed to appear:
Here's the kit as delivered and as built:
The kit went together easily enough, and sort of worked. However, the LEDs were of unequal brightness. Probing around with my multimeter showed that all LEDs were operating, but some were so dim they were impossible to see without looking closely. Maybe a better choice of resistor values might improve things. The following, very short, video shows the rather disappointing result when viewed in daylight. I didn't check it out in the dark. Disappointing!