25 Jul
1998
25 Jul
'98
4:52 a.m.
Date: Sat, 25 Jul 1998 17:14:46 +0100 (BST)
Reply-to: classiccmp(a)u.washington.edu
From: ard(a)p850ug1.demon.co.uk (Tony Duell)
To: "Discussion re-collecting of classic computers"
<classiccmp(a)u.washington.edu>
Subject: Re: Epson QX-10, CP/M
No, it's a true voice coil (I have a schematic in
front of me). There's a
Voice Coil Motor (VCM) that consists of a driving voice coil, a velocity
feedback coil and 3 photodetectors : track 0, and a pair of position
error signals.
Snipped of it's juicy descriptions...how interesting! Now I see
what
you meant.
Suppose, you have a floppy disk completely blank no tracks, just
spanking new one and try to format that in this?
I wondered how it knows it's right distrances between tracks and so
on.
It certainly isn't a linear stepper.
Okay!
The same drives IIRC are used in the TF20 floppy drive
for the HX20, BTW.
Whatever, I have not seen anything like this drive in my experience.
What machines did use these type with that neat voice-coil head
positioner? I find this voice-coil idea very reliable than stepper
themselves.
Jason D.
-tony
Jason D.
jpero(a)pop.cgocable.net