Brian J White wrote on 2002-07-12 05:41 UTC:
> >And it may in fact be the same situation as a floppy disk.  Made to 90 mm
> >width, but called a 3.5.

The 90-mm floppy disk was designed completely in metric by a Japanese
manufacturer (Sony). It became called the 3.5" floppy only when IBM
started using it in the US in 1986 with its PS/2 series of personal
computers.

> It may be...which is why I am asking for some kind of 
> source/proof/documentation.

The foreword of American National Standard X3.171-1989 (section 1.3)
*explicitely* says this product is a metric design and that the
millimeter dimensions given in the standard are the authoritative ones
(and the inch values are only provided to simplify life for US
manufacturers).

I have a copy of ANSI X3.171 here on my desk, and the outer dimensions
of the disk are exactly 94.0 x 90.0 x 3.3 mm, and the disk diameter is
exactly 85.80 mm

Markus

-- 
Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK
Email: mkuhn at acm.org,  WWW: <http://www.cl.cam.ac.uk/~mgk25/>

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