to get the Amiga to work with high density disks, the Commodore engineers took a little short cut and just spin the drive at half the normal RPM (150 instead of 300). this keeps the data rate the same, allowing the custom chip to remain unchanged.

this means you can't just use a standard PC floppy drive and expect it to work, even with a little PAL on the back. this drive has been modified.

as is typical in the Amiga community, the mods have been done in such a way to make them hard to reverse engineer. in this case, the rework wire is hair-thin magnet wire covered in silicone. try to remove the silicone, and it shreds the wire.