RE: Re: Who owns a 8050/8250 with tandon drives?

From: Martin Hoffmann-Vetter <>
Date: Fri, 14 Mar 2014 17:10:09 +0100
Message-ID: <004801cf3f9f$dff52a50$>
Hello Rob,

>> Don't know exactly what looks like tandon drives for 8050/8250 but
>> they have a different floppy locking system as regular ones.
>> Micropolis locking system have a sort of rectengular push button. To
>> load the floppy disk, you push the disk into the unit, then, when you
>> push (quite heavily) the button, the entire drive mecanism rotates to
>> complete lock. To remove the floppy, you push (quite heavily) again
>> the rectengular buton and the entire mecanism rotate back but does
>> not eject the disk; you have then to pull the buton to eject the
>> disk.

> I took a look at the service manual and they all look rather similar
> from the outside.

Yes, the Tandon drives are shown as the MPI or Shugart drives. But some Micropolis drives look likes so, too.

An other point is the type label on the rear side. Some units are labeled as 8050M or 8250M. This M means Micropolis or MPI. So if you find a unit labeled with 8050M or 8250M this isn't a tandon drive.

If you look into a drive (where the disc is interted) you can see some differences between the drive types. But that isn't easy. So you must compare some drives.

> I'll venture up into the attic with a screwdriver
> and a camera and over the weekend to see what I have.

If you open a 8050 or 8250, you can identify a tandon drive with the analog board. This isn't only on one drive. It's bigger ...

See some picture from inside a 8050/8250 drive:

MPI and Micropolis:
MPI: and
Micropolis: and
Tandon: (must be register at


BTW: If you open some drives and look into, can you look at the DOS roms, too? There are two version from DOS 2.5 (only 8050) with 901482-03/901482-04 and 901482-06/901482-07 and one version of DOS 2.7 (8050 or 8250) with 901487-01/901488-01 known. If you find an other version, it would be great to dump this, too.

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Received on 2014-03-14 17:00:03

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