[vcf-midatlantic] Bernoulli disksk, was Re: vcf-midatlantic] Mac OS 7.1 Terminal Emulator & BBS software

Dave McGuire mcguire at neurotica.com
Sun Mar 11 14:15:30 EDT 2018

On 03/08/2018 11:18 AM, David Riley via vcf-midatlantic wrote:
> On Mar 8, 2018, at 11:10, W2HX via vcf-midatlantic <vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
>> I have a vague recollection of products called bernoulli and syquest (sp?)?  But I don't remember the details of them.  I agree with Herb, Zip was quite ubiquitous..
> Bernoulli and SyQuest were essentially the predecessor formats to Zip and Jaz, respectively (though SyQuest drives and media were WAY more reliable than Jaz drives and media, which were mainly a great way to accidentally lose your data). I LOVED the 44 and 88 MB 5.25" SyQuest drives when I was younger. Like Zip and Jaz drives, they're SCSI, so they work well on vintage machines that can use SCSI.
> Dave McGuire is a Bernoulli fan and could probably elaborate more on those.

  I do love Bernoullis.  I was a heavy user of them since day one,
starting with the 10MB 8" dual full-height drive that was packaged in a
case that matched the styling of the IBM PC.  I then moved to 20MB 8",
and shortly thereafter got a job in a US Gov't defense-related
organization in which 44MB 5.25" Bernoulli subsystems were everywhere,
usually on PCs running DOS.  They were beloved in that world because
cartridges could be controlled by security personnel and kept in a vault.

  These drives and their disks were (and still are) incredibly reliable,
especially given the general nature of removable media.

  The 10MB and 20MB Bernoulli drives use a dumbed-down variant of SCSI,
but it's not quite SASI as I understand it.  They used drivers that you
installed via config.sys, and they required their own controllers for
ISA-bus use.  There isn't much logic on those controllers.  I recall
there being a couple of variants but I don't remember the numbers anymore.

  There are half-height versions of the 20MB 8" Bernoullis, but I don't
know if there are half-height versions of the 10MB ones.

  I have an early Kevex energy-dispersive X-ray spectrometer that's
built around a PDP-11/03, with a Z8000 as a numeric coprocessor, that
uses 20MB Bernoullis (half-height) emulating an RL subsystem.  That
system is in storage and I haven't looked at it in many years; I don't
recall how the Bernoulli subsystem is interfaced to the Qbus in that system.

  Today I use 44MB and 90MB 5.25" Bernoulli drives on one of my "home
PDP11s" (I have a few "personal" PDP-8s, PDP-11s, and VAXen which are at
home rather than at the LSSM, for soul-healing purposes), on CMD SCSI
host adapters, and they work great.

  Zip drives are essentially the same thing in a smaller form factor,
but Iomega decided to start marketing them to nontechnical people (hence
the new name, fancy colors, etc etc) because a lot of those people
couldn't even pronounce "Bernoulli" let alone know who he was or why the
original products bore his name.

  The 100MB Zip drives and disks are essentially indestructible.  I've
used hundreds of the disks and dozens of the drives, and I've seen
precisely ONE of the disks fail, and two drives.  One of the two drives
was killed by a friend of mine who always insisted that all wall wart
power adapters are actually the same, and all the numbers stamped on
them were only there to sell more wall warts.

  The higher-capacity Zip disks have reliability problems.  I won't go
near them for my own use for that reason.  And Jaz drives, for all of
their attractiveness, are all but useless.


Dave McGuire, AK4HZ
New Kensington, PA

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