> Wow! I'd love to see the 1971 vintage GCR tape controller, it must > have been the size of a 360 CPU! We had a GCR controller from > Storage Tech. in 1982 or so that was the same size as a PDP 11/44 > large cabinet. CDC Keystone drives (92185) had it integrated into > the 680x controller micro, which I thought was pretty amazing.
The IBM history pages seem to say that the initial 3420 offerings were 1600, in 1971, and that later models added GCR in 1973. The control unit, 3803, was similarly sized to the 3420 drive, iirc a bit shorter, but very roughly the same occupied square footage. https://www.ibm.com/ibm/history/exhibits/storage/storage_3420.html De
