Re: How to lobotomize unidisk 3.5 so it won't go boink and will work w/copy II+ bit copy?

[cturley2@aol.com (Cturley2)]

Here's the text for Lobotomizing the Unidisk.  And, it's reversible FYI :)
Retreived from the Sept.99 issue of GS WorldView and posted in full
below.
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Hacker's Corner - UniDisk 3.5 -> Apple 3.5 Conversion

A Reversible UniDisk 3.5 to Apple 3.5 Disk Drive Labotomy

Copyright � 1997 by Scott Gamon

In response to the recent questions asking how to make a UniDisk 3.5 work like
the Apple 3.5 drive...this also answers Randy Shackleford's comment of the
Finder polling all drives - Apple 3.5 drives are polled SILENTLY while UniDisk
3.5 drives must have their drive motors intermittently activated.

Upgrading your 3.5" drive: UniDisk 3.5 to Apple 3.5 modification

You've upgraded from an Apple IIe with a UniDisk 3.5 controller to a GS and now
you have a problem.  When the UniDisk 3.5 is connected to a GS, it is dog slow.

You have to set the interleave to 4:1 to make it run at a somewhat respectable
pace when loading those large GS programs and data files, but this causes speed
penalties when you take it to a friend's GS with an Apple 3.5 drive.  Even
worse, the drive is AUDIBLY AND VISIBLY POLLED by the Finder.  It sounds
terrible.  Now the Finder polls every drive, true.  But on the Apple 3.5 drive,
this polling does NOT start and stop the drive motor.  An Apple 3.5 drive is
silent, but aware in a program such as the Finder.  You wish you could
magically
transform your slowpoke, noisy UniDisk 3.5 into an Apple 3.5 (besides, this
would make it usable as a convenient external drive on your Mac sometimes...).

If your UniDisk 3.5 was manufactured in mid-1988 or later, you are in luck. 
The
later UniDisk 3.5 models can be (fully reversible) modified to work like an
Apple 3.5" drive.  Make sure the power is off and the drive is disconnected
from
the computer.  Get out your screwdriver set and get ready to roll!

First, remove the screws from the UniDisk 3.5's case and remove the ABS plastic
shell to expose the internal guts of the drive.  Check the label on the
mechanism: if it is a Sony model beginning with "#51W-" followed by two or
three
characters, your drive can be upgraded.  If the mechanism is different, you are
out of luck.  :(

Now that you have the UniDisk 3.5 opened and verified that the unit has the
right model mechanism, take a look at how the internal components of the drive
are put together.  There are two circuit boards and the drive mechanism.  The
interface cable is connected to the lower circuit board and there is a ribbon
cable that connects the top and bottom circuit boards together.

First, unplug the interface cable from the lower circuit board. Next, unplug
the
ribbon cable (that connects the two circuit boards) from the top board. 
Finally, plug the interface cable into the top circuit board.  When you are
finished, the interface cable that was originally connected to the bottom
circuit board should now be connected to the top one and there should be one
cable dangling.

Close the case by reassembling it with the screws and connect the drive to the
computer.  Now you can boot into the Finder and remove the UniDisk 3.5 driver
from the *:System:Drivers folder and use the Apple 3.5 driver instead.  Make
sure
to recopy all your 4:1 interleave disks to 2:1 interleave for fastest access.
This modification is also useful for Macintosh, IIc Plus, and Apple IIe with
SuperDrive controller users.

If you are still suffering the rattling noise and slow access of a UniDisk 3.5,
why not give this modification a try?  It is completely reversible should you
ever need to use the drive on a IIc or a IIe with a UniDisk 3.5 controller
again.

-Scott G.

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Hat's off to Scott G. for this. I trust it will take care of your requested
info needs.

Cheers,
Tom