On Mon, Aug 22, 2022 at 7:13 AM Paul Koning via cctalk < cctalk@classiccmp.org> wrote:
> > > > On Aug 21, 2022, at 8:35 PM, W2HX via cctalk <cctalk@classiccmp.org> > wrote: > > > > I always thought it was interesting how 5 1/4 is 3U (rack units). I > thought there might have been some relationship to that. But could have > been just coincidence. > > For floppies, likely yes. That fact did get used later on, in storage > arrays where you can line up 14 or so disk drives, standing on edge, in a > 3U 19 inch rack mounted system. > I thought the initial 5.25" Hard Disks had ISSUES[tm] operating on edge. I remember the RD50 (5MB in all its glory) being touted as also operating on edge for the desk-side cases for DEC Rainbows and Professionals (and later MircoPDP-11s). Warner
