Date   : Fri, 04 Oct 1991 09:41:55 PDT
From   : Sprague.Wbst311@xerox.com
Subject: Re: general (Floppy Drives on the Xerox 820-II)

> Does anyone know if "Memorex 550" floppy drives are
> compatible with Xerox 820-II's?

I know nothing about the Memorex 550 floppy drives, but .....

The Xerox 820-II uses "standard" 5.25" low density (360K on the PC) floppy
drives.  Just make sure the jumper is set to drive the Motor On signal with the
Drive Select.  (Most low density drives have this jumper, though few High
Density drives do).

Note that the 820-II's  with 5.25" drives all came with Shugart 400 (Single
sided) or 450 (double sided) full height floppy drives, which were powered by
the CPU's power supply.  If you were to replace them with newer half height
drives, they would consume less power, and using the CONFIGUR utility, you can
set the Step Rate to 6 mS, vs. the SA400's 30 mS and SA450's 20 mS Step Rates.
While it's still slow using floppies, you will see a noticable speed up in disk
access time.

Hmmm, also note that the boot disks on the Xerox 820-II assume a 30 mS Step
Rate as default.  If you have the SA450 drives, you should change it to 20 mS
on your "working" system disk (don't touch the originals).  The drives will
make less noise, and will be a little faster.

As far as 8" drives go, they need to be compatible with the Shugart 800 series,
and many are.

                               ~ Mike  (Sprague.Wbst311@Xerox.Com)