WOW!!!! $15k DEC PDP-8 CLASSIC MINICOMPUTER SYSTEM DIGITAL PDP8

[William Donzelli]

> Judging by the mainframes section of the IBM history pages
> (http://www-03.ibm.com/ibm/history/index.html) custom components
> arrived with the 360.  That may also when schematics stopped
> appearing, which makes sense.

For the mainframes, I am not sure when chip level schematics stopped
appearing. They were available in the late 1970s, with the 3031 (a TRUELY
huge stack of paperwork). S/360s and S/370s had very full maintenance
sets, as did S/3s, and pretty much all of the tapes, disks, punches,
readers, control units, and so forth. So, no, schematics definitely did
not stop appearing at the advent of the S/360. I suspect they went away
with the 308x line (which makes sense).

I do not think S/1s had full chip level schematics, as it was a board
swapper family, but the internals were very open. That was the point of
the family - finally IBM agreed (and encouraged) 3rd party support. They
actually managed to get some, as well (CDC under the Cambex name, for
example) before the line died.

The smaller machines (S/36 and such) were board swappers, I think. I have
never seen full maintenance docs on them.

William Donzelli
aw288 at osfn.org