Got this when took apart a VCR motor(?). On one side the disk looks like a circuit board full of yellow patches. Is this some type of gold plating? Copper? Somethings else?
By the way, on the other side (not shown in the photo) it has a ferrite disk with some copper wire inside.
By the way, on the other side (not shown in the photo) it has a ferrite disk with some copper wire inside.
