Iomega Bernoulli Box 20+20 (A220H)

[Chuck Guzis]

On 30 Jun 2010 at 20:01, Michael B. Brutman wrote:

> - Is it SCSI?  If so, what's the pinout on the back?  It has a 37 pin
> female connector that I'm not familiar with if it is SCSI.

Yes, it is.  The Iomega PC2 SCSI adapter has a DC37M on the bracket.  
I believe the pinout is the old Novell SCSI one:

http://sysdoc.doors.ch/BLACKBOX/17972.PDF

> - Where is the head mechanism?  Is it fairly robust and protected if
> there are no cartridges inserted?  This one has no major dents, but it
> has not been babied either.  I don't want to waste time on it if it's
> just going to be a heartache.  (I have enough of that already.)

I like the old Bernoulli boxes very much.  Because of the physics of 
the thing (Bernoulli's principle), the disks were pretty much 
uncrashable.  

You can demonstrate the principle for yourself by taking a playing 
card (or other semi-stiff card) and a common thread spool.  Push a 
pin through the middle of the card and insert the pin into the hole 
in the center of the spool (the pin simply keeps the card centered).  
Now with the card against the spool, blow through the spool as hard 
as you can.  You'd think that the card would be blown off, but it 
isn't--it floats against the spool on a thin cushion of air.

Ah-ha!  so if we substitute a disk for the card and a flat plate with 
a head embedded in the surface, we have a crashproof drive!

The other upside is that the whole affair is at a positive pressure 
to the atmosphere and so is self-purging.

Great stuff and very much unlike the Zip and Jaz abominations.

The early (5MB and 20MB) Bernoullis used a somewhat oversimplified 
SCSI command set.  I've never tried one on a late SCSI controller, 
but it should work.

--Chuck