From: cclist at
sydex.com snip
I believe that the earlier Micropolis 5.25"
floppy drives worked the
same way. I recall that when they first came out, they'd mangle the hub
area of a floppy because the spindle motor often had been turned off by
the host. Eventually, the design was modified so that the motor spun up
as the drive door closed, which solved the problem.
Before that, Dysan had experimented with putting a reinforcing ring on
their floppies. By the time high-density drives came out, the problem
had been solved so there was no need to reinforce the HD floppy hub area.
--Chuck
I'd always wondered why that was so.It has been handy to see which were 360K
as I don't think HD everhad the donut ( maybe rare ).Dwight