AFAIK, almost all 5.25' 1.2M drives had some sort
of dual-speed 300/360 RPM
capability under the hood, even if it wasn't
publicized.
Yeah, this "feature" has given me quite some headaches.
I use the TEAC FD-235 as the standard in my conversions systems. From new, there
were no problems reading PC and AS/400 disks on the same drive, but suddenly it
could stop reading PC or AS/400 disks.
At last, we found out that the error always occurred on drives assembled or
Malaysia or whereever, while the Japanese drives never had that error. A closer
inspection showed that the malayan motor was to blame, as it couldnt keep up
with the speed changes
cheers
Nico