Micropolis drives (was: Micro-Expander disks

From: Frank McConnell <fmc_at_reanimators.org>
Date: Tue Apr 17 12:13:30 2001

"Fred Cisin (XenoSoft)" <cisin_at_xenosoft.com> wrote:
> On 16 Apr 2001, Frank McConnell wrote:
> > Hmm, here I sit looking at one of a pair of Micropolis model 1115-VI.
> > It's a 5.25" full-height drive, serial 0372. Someone (not me) helpfully
> > wrote on it with a marker:

> They might be right. I had heard that Micropolis came out later with a
> 96TPI, but I've never seen it. The date code and the double sided is
> consistent with that. Is it really 2 sided? What kind of door assembly
> does it have?

Looking at it from the front, it looks like a typical full-height
Tandon as seen in an IBM PC or Shugart drive. Flat door, closes down
over center of slot. A printed-circuit board covers the top of the
drive. I think there are two sets of head leads that disappear into
the interior. The door, when closed, has a flange that pokes through
a slot in the board to interrupt an optical emitter/sensor pair.

What's funny is that the top hub appears to be fixed. The bottom hub is
mounted to a sort of sub-frame that pretty much covers the bottom of
the drive, and it pivots (drive shaft, drive motor and all) about the
middle of the outer frame as you close the door.

Of course, this makes looking into the interior of the drive more fun
than usual, because it's completely surrounded by stuff.

> But they might be mistaken, and have ASSUMED 96TPI due to it not being
> 48TPI, and/or having about 80 tracks. I've even seen people label 720K
> 5.25" drives as being 1/2M, "because it's NOT a 360K".

Yep, that is what you got me thinking.

-Frank McConnell
Received on Tue Apr 17 2001 - 12:13:30 BST