8 Mar
2023
8 Mar
'23
5:42 p.m.
On Mar 8, 2023, at 12:20 PM, Chuck Guzis via cctalk
<cctalk(a)classiccmp.org> wrote:
On 3/8/23 06:19, Paul Koning wrote:
I would disagree with that blanket assertion, for two reasons. One is that something
isn't an "evolutionary dead end" only if nothing later was inspired by it
and constructed, to some extent, along similar lines. In that sense the Uniservo tapes
are not at all a dead end; instead, they are the ancestor of all later tapes. Properties
like metal vs. plastic media and 6 tracks vs. 7 or 9 or more are details.
Second, I would consider a format to be significant if it had a major market presence and
major place in the technology space. In that sense, DECtape I clearly belongs -- being
either the primary or a significant secondary storage device for a decade or two of some
of the world's most successful computer lines.
Similarly, is DLT a "dead end"? It was captive to some extent until it spread
out, but then LTO replaced it. On the other hand, isn't LTO clearly an evolutionary
variant of DLT?
I'd agree that there are a number of other formats that were neither significant
players nor a significant influence on later work. The CDC 14-track tapes would fit that
description, and the Eliot or X1 10-track tapes most likely as well. But I would argue
that "if it wasn't an industry or ISO standard it doesn't count" is too
restrictive a view, especially if you aim to produce a history of the technology space.
paul
I wouldn't exclude those, certainly not if
they are relevant to the evolution of the technology. Are X1 tapes (and Eliott tapes if
they are the same format, which I don't know) in some way anticipating LINCtape and
DECtape? Are they an independent invention of roughly the same concept? For that matter,
would you exclude DECtape on the grounds that it's single vendor? I hope not. For
that matter, I suspect the Uniservo I format is specific to Univac, yet you can't very
well exclude that from a history of magnetic tape data recording.
I view "captive formats" such as DECtape to be evolutionary dead ends.
Consider, for example, the Datamatic 1000 tapes--I doubt that more than
a handful of people here have ever heard of the system. A captive format.
Or the early Uniservo metal tapes?