On 8/13/23 11:25, Tony Duell via cctalk wrote:
On Sun, Aug 13, 2023 at 5:20 PM Nigel Johnson Ham via
cctalk
<cctalk(a)classiccmp.org> wrote:
The DEC Rainbow RX50s only have one motor :-)
{being pedantic}
No they don't. They have 2. A permanent-magnet DC motor used to drive
both spindles and a stepper motor used to position both heads.
But I will agree it is a lot more usual for a dual floppy drive to
have separate spindle and positioner motors for the 2 disks
(Actually don't the Persci dual 8" drives with voice coil positioners
have a common spindle motor and head positioner for the 2 disks?)
Yes, absolutely. One spindle motor, with a floppy hub on
each end, and two heads on one voice coil positioner, one
for each floppy. I had one of those. The performance
improvement was VERY marginal. I had to take out the
solenoid that lifted the pad that loaded the media against
the head, the timing of the head loading somehow was all
wrong and allowed it to start writing before the pad had
fully loaded.
Jon