[TUHS] 3330s, 3340s, Winchesters... (was: /dev/drum)

[Paul Winalski]

On 4/23/18, Greg 'groggy' Lehey <grog at lemis.com> wrote:
>
> You're confusing the 3330 with the 3340: the latter was the
> Winchester, the first disk with an HDA.  The 3330 was the old-style
> disk pack in a cheese bell.  A variant (apparently not from IBM; CDC
> maybe?) of the same disk pack stored 300 MB, and we used a lot of them
> at Tandem in the 1970s and early 1980s.  I suppose they were pretty
> widespread.

The 3330 was, as you say, a conventional (for the day) disk drive
where the heads remain with the drive and you removed the platters
with a plastic cover very much like a cheese bell.  The 3340 was the
first IBM drive where the heads were sealed with the media.  The disk
packs looked somewhat like the front end of the Starship Enterprise,
with something like a roll-top desk cover at the back.  You put the
pack in the drive, the drive opened the roll-top desk and plugged into
the back of the head assembly, and you were in business.  After a few
years IBM discovered that nobody was removing their disks anymore, and
so the 3340's follow-ons were not removable.  But they still used the
sealed-media technology still in use in hard drives today.

Regarding the Winchester code name, I've argued about this with Clem
before.  Clem claims that the code name refers to various advances in
disk technology first released in the 3330's disk packs.  Wikipedia
and my own memory agree with you that Winchester referred to the 3340.

-Paul W.